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Tumor microenvironment-activated prodrugs have emerged as a promising strategy in precision medicine. However, the endogenous stimuli in the tumor microenvironment are often insufficient and unevenly distributed, impeding efficient and rapid prodrug conversion, necessitating the incorporation of complementary therapeutic strategies to amply treatment effectiveness. This study presents a self-synergistic therapeutic approach that combines hypoxia-activated paclitaxel prodrug (pro-PTX) with near-infrared-II (NIR-II) light-triggered photothermal therapy (PTT) for boosted tumor treatment. Initially, an organic polymer with strong NIR-II light harvesting capability, efficient photo-to-heat conversion, and excellent photostability was meticulously synthesized by introducing electron-withdrawing trifluoromethyl substituent. The high-performance NIR-II photothermal polymer then served as the matrix to encapsulate the hypoxia-responsive pro-PTX prodrug, forming the nanocore, on which the cell membrane derived from natural killer (NK) cells was further cloaked. The biomimetic nanopaltform exhibited a superior affinity towards tumor cells compared to normal cells, owing to the inherent tumor-recognition capability of NK cell membrane proteins. Upon exposure to NIR-II laser, the photothermal agent induced localized hyperthermia, facilitating not only direct tumor eradication but also exacerbating hypoxia within the tumor microenvironment. This, in turn, expedited the release of hypoxia-responsive prodrugs. Consequently, the synergistic effect of NIR-II PTT and chemotherapy efficiently induced cancer cell apoptosis and inhibited tumor growth. The developed nanoplatform, integrating hypoxia-responsive prodrug, high-performance NIR-II PTT agent-mediated complementary phototherapy, and NK cell-inspired active targeting, represents a promising strategy for precise and boosted tumor treatment. [Display omitted] • A nanoplatform integrates hypoxia-responsive prodrug, NIR-II PTT phototherapy, and NK cell-inspired active targeting. • Photothermal tumor ablation disrupted blood flow, creating severe hypoxia and expediting prodrug release. • NIR-II PTT and prodrug combo enhanced cancer cell apoptosis, suppressed tumor growth, and reduced pulmonary metastasis. [ABSTRACT FROM AUTHOR]

During myogenesis and regeneration, the proliferation and differentiation of myoblasts play key regulatory roles and may be regulated by many genes. In this study, we analyzed the transcriptomic data of chicken primary myoblasts at different periods of proliferation and differentiation with protein‒protein interaction network, and the results indicated that there was an interaction between cyclin-dependent kinase 1 ( CDK1 ) and ribonucleotide reductase regulatory subunit M2 ( RRM2 ). Previous studies in mammals have a role for RRM2 in skeletal muscle development as well as cell growth, but the role of RRM2 in chicken is unclear. In this study, we investigated the effects of RRM2 on skeletal muscle development and regeneration in chickens in vitro and in vivo. The interaction between RRM2 and CDK1 was initially identified by co-immunoprecipitation and mass spectrometry. Through a dual luciferase reporter assay and quantitative real-time PCR, we identified the core promoter region of RRM2 , which is regulated by the SP1 transcription factor. In this study, through cell counting kit-8 assays, 5-ethynyl-2′-deoxyuridine incorporation assays, flow cytometry, immunofluorescence staining, and Western blot analysis, we demonstrated that RRM2 promoted the proliferation and inhibited the differentiation of myoblasts. In vivo studies showed that RRM2 reduced the diameter of muscle fibers and slowed skeletal muscle regeneration. In conclusion, these data provide preliminary insights into the biological functions of RRM2 in chicken muscle development and skeletal muscle regeneration. [ABSTRACT FROM AUTHOR]

The present study aims at investigating alterations of rat intestinal homeostasis induced by 7-day simulated microgravity (SMG) effect through a proteomic approach. Tail-suspension model was used to simulate microgravity effect and a label-free quantitative proteomic strategy was employed to determine proteins in rat intestine. As a result, 717 differently expressed proteins were identified and 29 proteins were down-regulated while 688 proteins were up-regulated. 283 out of 717 proteins were categorized into 7 clusters with DAVID (version 6.8). The three highest enrichment scores were annotation cluster I about cell-cell adhesion (46 proteins with enrichment score of 16.67), annotation cluster II about carbohydrate metabolism (32 proteins with enrichment score of 6.17) and annotation cluster III about activity of pepdtidase (17 proteins with enrichment score of 4.74). Results of rat intestine proteomics indicate that SMG might disrupt intestinal homeostasis, which possibly resulted in opening of intestinal epithelial barrier (IEB), potentially leading to risk of systemic inflammatory response (SIR) and inflammatory bowel diseases (IBD). The present results also provide some useful information for mechanism and countermeasures of intestine injuries induced by microgravity. • A proteomic analysis of rat intestine under simulated microgravity was conducted based on label-free quantitative strategy. • 717 differentially expressed proteins was identified and categorized into 7 clusters. • Simulated microgravity might have influence on rat intestinal structural integrity, metabolism and oxidative stress. [ABSTRACT FROM AUTHOR]

The safety of herbs containing aristolochic acids (AAs) has become a widespread concern. Previous reports indicate that AAs are highly nephrotoxic and carcinogenic, although there are more than 170 analogues of aristolochic acid. Not all AAs have the same degree of nephrotoxicity or carcinogenicity. Previous studies have found that aristolochic acid IVa (AA-IVa), the principal component of AAs within members of the Aristolochiaceae family, especially Asarum , a commonly used herb in China, has essentially no significant nephrotoxicity. However, several studies, including ours, have shown that aristolochic acid I (AA-I) is clearly nephrotoxic. The focus of the study was to elucidate the molecular mechanism responsible for the difference in nephrotoxicity between the AA-I and AA-IVa. Mice were administered with AA-I or AA-IVa for 22 weeks through the oral route, followed by a 50-week recovery time. The kidney tissues of mice were extracted at the end of 22 weeks. Pathological examination and proteomic detection (tandem mass tagging (TMT) and phosphorylated proteomics) were performed on the kidney tissue to investigate the key signaling pathways and targets of AAs-induced renal interstitial fibrosis (RIF). The key signaling pathways and targets were verified by Western blot (WB), siRNA transfection, and luciferase assays. AA-I caused severe nephrotoxicity, high mortality, and extensive RIF. However, the same AA-IVa dosage exhibited almost no nephrotoxicity and does not trigger RIF. The activation of the p38-STAT3-S100A11 signaling pathway and upregulated expression of α smooth muscle actin (α-SMA) and Bcl2-associated agonist of cell death (Bad) proteins could be the molecular mechanism underlying AA-I-induced nephrotoxicity. On the other hand, AA-IVa did not regulate the activation of the p38-STAT3-S100A11 signaling pathway and had relatively little effect on the expression of α-SMA and Bad. Consequently, the difference in the regulation of p38-STAT3-S100A11 pathway, α-SMA, and Bad proteins between AA-I and AA-IVa may be responsible for the divergence in their level of nephrotoxicity. This is the first study to reveal the molecular mechanism underlying the difference in nephrotoxicity between AA-I and AA-IVa. Whether STAT3 is activated or not may be the key factor leading to the difference in nephrotoxicity between AA-I and AA-IVa. [Display omitted] [ABSTRACT FROM AUTHOR]

• The purgative mechanism of MA was revealed for the first time. • Inhibition of glucose absorption causes a chain reaction in the intestine. • The purgative effect of MA reshapes the gut microbiota and microenvironment. • Stimulating intestinal peristalsis is not a sufficient condition for purgative. • The purgative effect of MA is stereoscopic and reversible. Multiflorin A (MA) is a potential active ingredient of traditional herbal laxative, Pruni semen, with unusual purgative activity and an unclear mechanism, and inhibiting intestinal glucose absorption is a promising mechanism of novel laxatives. However, this mechanism still lacks support and a description of basic research. This study aimed to determine the main contribution of MA to the purgative activity of Pruni semen and elucidate the effect intensity, characteristics, site, and mechanism of MA in mice, and determine the novel mechanism of traditional herbal laxatives from the perspective of intestinal glucose absorption. We induced diarrhoea in mice by administering Pruni semen and MA, and the defecation behaviour, glucose tolerance, and intestinal metabolism were analysed. The effects of MA and its metabolite on peristalsis of the intestinal smooth muscle were evaluated using an intestinal motility assay in vitro. Intestinal tight junction proteins, aquaporins, and glucose transporters expression were analysed using immunofluorescence; gut microbiota and faecal metabolites were analysed using 16S rRNA and liquid chromatography-mass spectrometry. MA administration (20 mg/kg) induced watery diarrhoea in over half of the experimental mice. The activity of MA in lowering peak postprandial glucose levels was synchronous with purgative action, with the acetyl group being the active moiety. MA was metabolised primarily in the small intestine, where it decreased sodium-glucose cotransporter-1, occludin, and claudin1 expression, then inhibited glucose absorption, resulting in a hyperosmotic environment. MA also increased the aquaporin3 expression to promote water secretion. Unabsorbed glucose reshapes the gut microbiota and their metabolism in the large intestine and the increasing gas and organic acid promoted defecation. After recovery, the intestinal permeability and glucose absorption function returned, and the abundance of probiotics such as Bifidobacterium increased. The purgative mechanism of MA involves inhibiting glucose absorption, altering permeability and water channels to promote water secretion in the small intestine, and regulating gut microbiota metabolism in the large intestine. This study is the first systematic experimental study on the purgative effect of MA. Our findings provide new insight into the study of novel purgative mechanisms. [Display omitted] [ABSTRACT FROM AUTHOR]

Chinese dwarf cherry (Ouli) is a native shrub in northwest China with high ecological value, but the nutritive potential remains to be explored. In this study, the total content of polyphenols, flavonoids, proanthocyanidins, and anthocyanins of Ouli from 30 germplasms were measured, and the antioxidant activities were evaluated by FRAP and ABTS assays. The polyphenol profile was determined by ultra-high-performance liquid chromatography-high resolution mass spectrometry. Grey relational analysis and partial least squares were utilized to build chemometrics models for selecting antioxidant compounds. The contents of total flavonoids, proanthocyanidins, phenols and total anthocyanidins of 30 germplasms of Ouli were 119.92–668.76 mg/100 g fresh weight (FW), 90.81–555.44 mg/100 g FW, 148.42–390.43 mg/100 g FW, 0.02–17.26 mg/100 g FW, respectively. A total of 61 compounds were identified, including 40 flavonoids (26 flavonols, 4 anthocyanins, 6 dihydroflavonols, 2 dihydrochalcones, and 2 flavones), 12 proanthocyanidins, 6 phenolic acids, and 3 types of other class compounds (one stilbene and two phenols). The proanthocyanidin compounds in Ouli contributes most to the total antioxidant capacity with the antioxidant rank that procyanidin trimer > tetramer > dimer ≈ monomer. Catechin and procyanidin B1 were the most abundant compounds and were 18.45–162.50 μg/g FW and 30.52–149.42 μg/g FW, respectively. Shanxi (SX) 2 and SX10 could be considered as potential germplasms, and proanthocyanidins could be chosen as a characteristic nutrient evaluation index of Ouli. This study not only takes a key step to lay the groundwork for further research of Ouli but also provides a reference for the discovery of the functional ingredients of other foods. [Display omitted] [ABSTRACT FROM AUTHOR]

Cuticular wax is the outermost thin hydrophobic layer covering the surface of aerial plant parts, which provides a primary waterproof barrier and protection against different environmental stresses. The aim of the present study was to investigate the role of ethephon, as an ethylene-releasing compound, in counteracting drought stress by modulating cuticular wax biosynthesis, water balance, and antioxidant regulation in maize seedlings. Our results showed that ethephon significantly increased the ethylene evolution rate, regulate the expression of cuticular wax synthesis regulatory gene ZmERE and the wax biosynthetic genes ZmGL1 , ZmGL15 , ZmFDH1 , and ZmFAE1 , and promote cuticular wax accumulation in maize seedlings under normal or drought stress conditions. Moreover, ethephon was shown to might markedly reduce water loss and chlorophyll leaching in leaves, and maintain higher relative water content and leaf water potential under drought stress. Ethephon significantly decreased malondialdehyde and hydrogen peroxide concentrations and electrolyte leakage, but increased the accumulation of proline and the activities of SOD, POD, and CAT. In addition, ethephon resulted in an increase in the ratio of root and shoot under drought stress. These results indicated that ethephon could improve maize performance under drought stress by modulating cuticular wax synthesis to maintain water status and membrane stability for plant growth. [ABSTRACT FROM AUTHOR]

Although much is known about the pharmacological activities of Dragon's Blood (DB, a traditional Chinese herb), its metabolism in human liver microsomes (HLMs) and the cytochrome P450 (CYP) enzymes has not been studied. This study aims to identify the metabolic profile of five flavonoids (loureirin A, loureirin B, loureirin C, 7,4′-dihydroxyflavone and 5,7,4′-trihydroxyflavanone) from DB in HLMs as well as the CYP enzymes that are involved in the metabolism of them. High-resolution mass spectrometry was used to characterize the structures of their metabolites and 10 cDNA-expressed CYP enzymes (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4 and CYP3A5) were used to verify which isozymes mediate in the metabolism of the metabolites. Totally, 29 metabolites including 10 metabolites of loureirin A, 10 metabolites of loureirin B, 4 metabolites of loureirin C, 2 metabolites of 7,4′-dihydroxyflavone and 3 metabolites of 5,7,4′-trihydroxyflavanone were elucidated and identified on the basis of the high-resolution MS n data. The metabolic profile of the five flavonoids in HLMs involved hydroxylation, oxidation and demethylation. Among them, hydroxylation was the predominant biotransformation of the five flavonoids in HLMs, occurring in combination with other metabolic reactions. Assay with recombinant P450s revealed that CYP2C9 and CYP2C19 played an important role in the hydroxylation of flavonoids in HLMs. To the best of our knowledge, this is the first in vitro evaluation of the metabolic profile of loureirin A, loureirin B, loureirin C, 7,4′-dihydroxyflavone and 5,7,4′-trihydroxyflavanone in HLMs. [ABSTRACT FROM AUTHOR]

An ocular iontophoretic device using a biocompatible planar PEDOT electrode is reported. In vivo experiments on rabbit eyes demonstrated that the device can realize ocular iontophoresis effectively, simply, and conveniently. Compared with conventional eye cups, this device can be placed under the eyelid and deliver ions through a small area on the eyeball, reducing tissue damage during ion penetration. Devices were fabricated in different sizes for different cases. The efficiency was a function of the current, work time and solvent water content. The highest iontophoretic efficiency observed in the in vivo experiments was 396 ng/mL, while the efficiency observed in the controlled experiments was only 2.69 ng/mL. The temperature distribution was simulated and measured, and thermal injuries were not observed under an applied current of 1.5 mA. [ABSTRACT FROM AUTHOR]

Demand for water, energy and food is increasing driven by a rising global population, changing diets, warming climate and economic growth. Wheat-maize double cropping system, as one of the best trials in ensuring sustainable food security, is experiencing various optimizing irrigation management and tillage practices in the North China Plain. However, previous studies mainly focused on their influences on crop yield and water use efficiency. Comprehensive analysis of water-energy-food for the practices was limited. Therefore, a life cycle assessments based water–energy–food (WEF) nexus analysis was conducted using data from a 7-year two-factor split-plot field experiments with four tillage (NT, no-tillage; RT, rotary tillage; PT, plow tillage; CT, local current tillage) and three irrigation managements (W1, pre-planting irrigation for wheat + pre-planting irrigation for maize; W2, pre-planting + jointing irrigation for wheat + pre-planting irrigation for maize; and W3, pre-planting + jointing + anthesis irrigation for wheat + pre-planting irrigation for maize; 75 mm each time). The results indicated that irrigation, fertilizer and diesels input were the top three items for water and energy consumption. Irrigation managements significantly altered wheat and annual yield but not for maize yield. Tillage practices primarily altered diesel input to affect energy mass and energy economic productivity. During wheat season, W3PT obtained the highest yield at 8.69 t ha−1 and highest net income at 8.27 ¥ ha−1. With the same tillage practice, W1 had the best performance in water and energy consumption and mass productivity, while W2 had the highest water and energy economic productivity. In terms of different tillage practices with the same irrigation amount, NT consumed lowest energy, but its lowest wheat yield offset its benefits as well. During maize season, the yields were insensitive for irrigation and tillage practices. NT and CT were substantially beneficial regarding energy input, which further resulted in good performance in terms of energy mass and economic productivity under the same irrigation treatment. Throughout the year, lower water and energy consumption and higher resource productivity offset the yield and income loss under W1CT to accomplish highest value of WEF nexus index. Thus it is the optimal tillage and irrigation management pattern in the wheat-maize double cropping system of the North China Plain achieving cleaner production. This study contributed a new case to using WEF nexus analysis and offered new reference data and effective suggestions for selecting proper filed management in the double cropping system to achieve sustainable development goals with carbon peaking and carbon neutrality. [Display omitted] • LCA based WEF nexus was used to optimize irrigation & tillage of wheat-maize rotation. • The local current tillage mode + irrigate pre-sowing only was the optimal pattern. • Lower water and energy input and higher resource productivity offset yield and income loss. • Irrigation, fertilizer and diesels were the top 3 items for water and energy consumption. • The influences of irrigation and tillage management were more remarkable for wheat. [ABSTRACT FROM AUTHOR]

In the present work, AlSiTiCrNiCu high entropy alloy (HEA) has been used in as-cast Al-5wt%Cu alloy to investigate the effect of HEA addition level (0.3 wt% and 0.6 wt%) on the microstructure and mechanical performance. The results revealed that the addition of HEA has a distinct influence on the size and morphology of primary α-Al and second phases in the cast Al-5wt%Cu alloy. When 0.3 wt% and 0.6 wt% HEA was added to Al-5wt.%Cu alloy, the primary α-Al dendrites was obviously refined and the mean size of α-Al grains was significantly reduced from 372.5 μm to 183.4 μm and 156.3 μm, respectively. Meanwhile, the size and morphology of θ-Al 2 Cu phases distributing inter-dendritic zone occurred to obvious change with increase of HEA addition concentration. In addition, the θ-Al 2 Cu phases disappeared and eutectic Al 3 CuNi phases precipitated after adding the HEA in Al-5wt%Cu alloy. Compared with θ-Al 2 Cu phases, the width was decreased and the continuity of Al 3 CuNi was improved when HEA was added to Al-5wt%Cu alloy. Moreover, it was found by TEM that some novel nano-particles precipitated from Al-5wt%Cu alloy with the addition of HEA in solidification, which uniformly distributed in the α-Al matrix. The yield strength, ultimate tensile strength and elongation of Al-5wt%Cu alloy with 0.6 wt.% HEA addition were significantly increased by 19.7%, 20.1% and 92.3%, respectively. The improvement of mechanical properties was attributed to change of morphology and decreasing size of α-Al and Al 3 CuNi phases. In addition, a new plate-like structure precipitated which morphology is similar to θ phase and multi-elements nano-particles formed, which strengthened the Al-5wt%Cu alloy. • HEA addition can effectively refine the α-Al grains of Al-5wt.%Cu alloy from dendrites to equiaxed grains. • The addition of HEA can precipitate nano-sized AlCuNi phases and AlSiTiCrNiCu particles precipitate in Al-5wt.%Cu alloy. • The improvement of strength is mainly attribute to the Orowan strengthening and solid solution strength. [ABSTRACT FROM AUTHOR]

Marring the reversible covalent chemistry with BODIPY dye, which is a superfamily of fluorophores with striking photophysical performances, would enable a panel of diverse dynamic fluorescent probes for biomedical applications. Herein we show that structural manipulation of BODIPY allows rational tuning of α -site or meso -site activation as well as the spectral response toward nucleophiles. By rational molecular design, we have obtained a highly specific and reversible GSH probe, α BD-GSH , which exhibits a tremendously fast and dynamic fluorescence response within the wide physiological GSH concentration range of 0–8 mM. We successfully applied α BD-GSH to real-time imaging of intracellular GSH dynamics in different cell lines. In light of the remarkable photophysical properties and synthesis flexibility of BODIPY dyes, the current findings will help to design more reversible BODIPY-based fluorescent probes targeting various bio-species. Image 1 • We successfully introduced BODIPY family to the design of dynamic fluorescence probes, and synthesized the hitherto fastest α , β -unsaturated ketone/amide-based dynamic fluorescent GSH probe. • The utility of α BD-GSH for real-time visualization of intracellular GSH dynamics was demonstrated in different cell lines. • We established, for the first time, that structural manipulation of BODIPY allows rational tuning of α -site or meso -site activation as well as the spectral response toward nucleophiles. This fundamental finding opens the door for the design of more BODIPY-based dynamic fluorescent probes. [ABSTRACT FROM AUTHOR]

• Carbohydrates in the basal stems were continuously degraded as the major storage energy for shoot elongation in vitro. • The shoot tips exhibited greater capacity for ROS scavenging compared with the basal stems. • Comparative proteomics revealed the different metabolism patterns in the basal stems and the shoot tips. Dodder is a holoparasitic flowering plant that re-establishes parasitism with the host when broken off from the host. However, how in vitro dodder shoots recycle stored nutrients to maintain growth for reparasitizing hosts is not well characterized. Here, the spatial and temporal distribution characteristics of carbohydrates and reactive oxygen species (ROS) were analysed to explore the mechanism of recycling stored nutrients in dodder shoots in vitro. Our results showed that in vitro dodder shoots grew actively for more than 10 d, while dry mass decreased continuously. During this process, the transcript levels and activities of amylases gradually increased until 2 d and then declined in basal stems, which induced starch degradation at the tissue, cellular and subcellular levels. Additionally, the distribution characteristics of H 2 O 2 and the activities and transcript levels of antioxidant enzymes indicated that shoot tips exhibited more robust ROS-scavenging capacity, and basal stems maintained higher ROS accumulation. Comparative proteomics analysis revealed that starch in basal stems acted as an energy source, and the glycolysis, TCA cycle and pentose phosphate pathway represented the energy supply for shoot tip elongation with time. These results indicated that efficient nutrient recycling and ROS modulation facilitated the parasitism of dodder grown in vitro by promoting shoot elongation growth to reach the host. [ABSTRACT FROM AUTHOR]

The effects of Sc addition on the primary α-Al phases and novel nano-AlCu phases were investigated in Al-5%Cu alloys without and with 0.8%Sc. The microstructural evolution was characterized by scanning electron microscopy (SEM) and transmission electron microscope (TEM) with energy dispersive X-ray spectroscopy (EDS). In the study, the novel ribbon nano-AlCu phases were found in as-cast Al-5%Cu alloy and the average length is about 200–300 nm. When 0.8%Sc was added into the Al-5%Cu alloy, the α-Al phases were obviously refined from coarse dendrites to fine equiaxed grains and the average grains size decreased to 29.8 μm. Moreover, the number of nano-AlCu phases significantly increases, but the length and width obviously decrease. In addition, the nano-AlCu phases have a good lattice matching relationship with α-Al phases, which can act as a precursor refining α-Al grains. • Sc can not only refine the α-Al grains, but also can change the morphology of θ-Al 2 Cu phases. • A novel nano-AlCu phase is found in Al-5%Cu alloys and the nano-Al 3 Sc particles can form in Al-5%Cu-0.8%Sc alloy. • The formation of nano-Al 3 Sc can restrict the growth of nano-AlCu phase and act as the precursors refining α-Al. [ABSTRACT FROM AUTHOR]

Grain refinement is one of the effective methods to improve the yield strength and toughness of Al-Cu alloys. The effects of Sc addition (0.2%, 0.4%, 0.6%, 0.8% and 1.0 wt%) on the microstructural evolution and mechanical properties of as-cast Al-5%Cu alloys were studied. The as-cast samples were characterized by optical microscope (OM), transmission electron microscopy (TEM), scanning electron microscope (SEM) and electron probe microanalysis (EPMA). The results revealed the primary α-Al occurred to obvious change from developed dendrites to fine equiaxed grains with the increasing Sc content in Al-5%Cu alloy. When the addition concentration of Sc reaches 0.8%, the developed α-Al dendrites were significantly refined and the average size of α-Al decreased from 218.3 μm to 29.6 μm. Moreover, the morphology and size of θ-Al 2 Cu phases of Al-5%Cu alloy caused noticeable changes with the increase of Sc concentration. Mechanical properties test illustrated that the ultimate tensile strength (UTS), yield strength (YS) and elongation (El) increased by 61.59%, 66.82% and 57.20%, respectively, which could be attributed to microstructure refinement and fine Al 3 Sc particle precipitate. • Sc can significantly refine the α-Al phase from coarse dendrites to uniform fine equiaxed grains in Al-5%Cu alloy. • The addition of Sc change the morphology of θ-Al 2 Cu from discontinuous to continuous tissues. • The YS and UTS was improved by 61.59% and 66.82% and the El was enhanced by 57.20% when the addition of Sc reached 0.8%. [ABSTRACT FROM AUTHOR]

• Ethephon repressed internode cell elongation but advanced growth process. • Ethephon increases secondary cell wall related genes expression to inhibit elongation. • Ethephon promotes ethylene evolution but decreased IAA and GAs level in the internode. • ERF, MYB and NAC are involved in cell wall and hormone related pathway regulation. Ethephon efficiently regulates plant growth to modulate the maize (Zea mays L.) stalk strength and yield potential, yet there is little information on how ethylene governs a specific cellular response for altering internode elongation. Here, the internode elongation kinetics, cell morphological and physiological properties and transcript expression patterns were investigated in the ethephon-treated elongating internode. Ethephon decreased the internode elongation rate, shortened the effective elongation duration, and advanced the growth process. Ethephon regulated the expression patterns of expansin and secondary cell wall-associated cellulose synthase genes to alter cell size. Moreover, ethephon increased the activities and transcripts level of phenylalanine ammonia-lyase and peroxidase, which contributed to lignin accumulation. Otherwise, ethephon-boosted ethylene evolution activated ethylene signal and increased ZmGA2ox3 and ZmGA2ox10 transcript levels while down-regulating ZmPIN1a , ZmPIN4 and ZmGA3ox1 transcript levels, which led to lower accumulation of gibberellins and auxin. In addition, transcriptome profiles confirmed previous results and identified several transcription factors that are involved in the ethephon-modulated transcriptional regulation of cell wall biosynthesis and modification and responses to ethylene, gibberellins and auxin. These results indicated that ethylene-modulated auxin and gibberellins signaling mediated the transcriptional operation of cell wall modification to regulate cell elongation in the ethephon-treated maize internode. [ABSTRACT FROM AUTHOR]

Straw return has been widely implemented to sequester soil organic carbon (SOC) and enhance soil quality in rice-wheat cropping systems, however, the mechanism through which it influences microbial assemblages into mediating biochemical metabolic pathways in soil remains ambiguous. This study aimed at investigating the composition and assembly of soil microbial communities and the soil metabolome prevailing across four straw return practices (control: no straw return; RR: rice-straw return; WR: wheat-straw return; DR: both rice- and wheat-straw return) during wheat cultivation on a rice-wheat rotation field. Straw return primarily altered the abundance of lipids (LL), organic acids (OA), organic nitrogen compounds, and benzenoids, with DR having a greater impact on soil metabolites than WR or RR. Besides being predominantly present in the lipid (LM) and amino acid (AAM) metabolic pathways, these differentially expressed metabolites (DEMs) were also dispersed throughout the nucleotide, xenobiotic, and secondary metabolite pathways. Straw return substantially elevated homogeneous selection in the order DR > WR > RR > control. The links of taxa to LM and AAM occupied by 64.9% in the DEMs-microbial taxa correlation network, with majority of taxa being derived from the keystone modules of the microbial network. Furthermore, these taxa potentially modulated variations in microbiota assembly by 27–45.1%, soil metabolites by 13.3–70.7%, and soil nutrient properties by 24.8–49.6%; and their removal evidently mitigated the natural connectivity of the microbial network. Structural equation modeling depicted that straw return exerted positive effects on LL and OA by regulating microbial assembly. Therefore, our results demonstrated that straw return drive microbial community assembly to dominate the taxa mediating soil LM and AAM for enhancing SOC sequestration and soil quality. • Double-crop straw return had more DEMs belonged to lipids and organic acids. • Straw return mainly drove bacteria species of keystone module to regulate metabolites. • Straw return increased the importance of deterministic selection. • Taxa linked lipid and amino acid metabolism were key to community assembly. [ABSTRACT FROM AUTHOR]

Abstract: No tillage (NT) of summer maize (Zea mays L.) is the dominant agricultural practice in the annual double-cropping system of winter wheat–summer maize in the North China Plain, and the long-term NT is often unfavorable for the growth of maize roots. The aim of this study was to evaluate the effect of 2-year-old rotary tillage (RT) and plowing tillage (PT) based at NT soil on root growth, spatial distribution, nutrients uptake and grain yield in Wuqiao of the North China Plain. PT and RT significantly increased root biomass across 0–40cm soil profile in the whole growth stage. Lower bulk density under PT and RT was compared to under NT in the 0–20cm soil profile, and penetration resistance under NT was significantly higher than under PT and RT in the 0–30cm soil profile. Root length density (RLD) in the uppermost soil profile (0–10cm) had no evident differences among tillage practices at silking stage, but RLD under PT and RT was significantly greater than under NT at maturity. Moreover, RLD and root surface density (RSD) were significantly higher under PT than under NT in the topmost layer, 10–50cm soil profile, but there were no differences in RLD and RSD among tillage practices at the deeper soil profile below 60cm. PT and RT markedly improved the root-bleeding sap rate in the whole growth stages in 2011 and most growth stages in 2012. In addition, NH4 + and NO3 − delivery rate under PT were significantly higher than those under RT and NT in 2011 and 2012, and under RT were significantly higher than under NT in 2012. The delivery rate of P, K, Ca, Mg, Fe and Zn in bleeding sap under PT was significantly higher than those under NT at different growing stages across the two years. Our results suggested that short-term PT and RT could increase root biomass, improve root spatial and temporal distribution, and enhance nutrients uptake, which resulted in higher biomass and grain yield of summer maize in the North China Plain. [Copyright &y& Elsevier]

Abstract: Improving the reliability of bus service has the potential to increase the attractiveness of public transit to current and prospective riders. An understanding of service reliability is necessary to develop strategies that help transit agencies provide better services. However, few studies have been conducted analyzing bus reliability in the metropolis of China. This paper presents an in-depth analysis of service reliability based on bus operational characteristics in Beijing. Three performance parameters, punctuality index based on routes (PIR), deviation index based on stops (DIS), and evenness index based on stops (EIS), are proposed for the evaluation of bus service reliability. Reliability involves routes, stops, punctuality, deviation, and evenness. The relationship among the three parameters is discussed using a numerical example. Subsequently, through a sampling survey of bus lines in Beijing, service reliability at the stop, route, and network levels are estimated. The effects of route length, headway, the distance from the stop to the origin terminal, and the use of exclusive bus lanes are also analyzed. The results indicate low service reliability for buses in Beijing and a high correlation between service reliability and route length, headway, distance from the stop to the origin terminal, and the provision of exclusive bus lanes. [Copyright &y& Elsevier]