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The effect of weak intercalated layers on the seismic response of rock slopes is investigated. Dozens of rock slopes containing weak intercalated layers are modeled in FLAC. The geometric property of the weak intercalated layer has a significant effect on the seismic slope response. The responses are generally greater as the thickness of the weak intercalated layer increases. The slope case with a 10-m-thickness and 20°-dip-angle weak intercalated layer yields the strongest dynamic response. A predictive model for the amplification of peak ground acceleration is developed, which can be used to estimate the acceleration amplifications for weak-layer-containing rock slopes. [ABSTRACT FROM AUTHOR]

Myocardial fibrosis is a critical factor in the development of heart failure with preserved ejection fraction (HFpEF). Linggui Qihua decoction (LGQHD) is an experienced formula, which has been proven to be effective on HFpEF in clinical and in experiments. Objective. This study aimed to observe the effect of LGQHD on HFpEF and its underlying mechanism. Methods. Spontaneously hypertensive rats (SHR) were induced with high-glucose and high-fat to establish HFpEF models and were treated with LGQHD for 8 weeks. The heart structure was detected by echocardiography, and the histopathological changes of the myocardium were observed by hematoxylin-eosin (HE) and Masson staining. Reverse transcription PCR (RT-PCR) and western blot were used to detect mRNA and protein expression of the target gene in rat myocardium. Results. In this study, LGQHD improved cardiac morphology and atrial fibrosis in HfpEF rats, decreased tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNA expression, up-regulated matrix metalloproteinase-9 (MMP-9) mRNA expression, and inhibited the expression of angiotensin II (Ang II), angiotensin II type 1 receptor (AT1), transforming growth factor β1 (TGF-β1), Smad2/3 mRNA, and protein in myocardial tissue of HFpEF rats. Conclusion. LGQHD can suppress atrial fibrosis in HFpEF by modulating the TGF-β1/Smad2/3 pathway. [ABSTRACT FROM AUTHOR]

Given the health and environmental risks associated with pesticide misuse, achieving zero pesticide residues is pivotal in Agriculture 4.0. Traditional detection methods such as HPLC and GC-MS are both complex and time-consuming. In contrast, surface-enhanced Raman scattering (SERS) offers rapid detection and high sensitivity, aligning with the efficiency and accuracy requirements of Agriculture 4.0. In this study, we developed a high-performance flexible substrate using a simple chemical synthesis method. We used material adsorption, anisotropic charge attraction and electron migration to facilitate the growth of the substrate material, which promoted more 'hot spots' and electron transfer, and continued optimisation of the preparation process, which resulted in a significant increase in spectral intensity. The substrate demonstrated outstanding detection capability, with a detection limit of 10−15 M for thiabendazole (TBZ). In practical fruit testing, TBZ residue concentrations on the surface of American cherries could be detected as low as 10−8 mg/mL, well below China's prescribed limit of 5 mg/kg. Relative to previous work in the field of pesticide detection, our study has lower detection limits and concentrations, as well as lower cost and simpler preparation, which provide more options for the detection of very low concentrations of hazardous substances. At the same time, it was confirmed that SERS is consistent with the zero pesticide residue goal of Agriculture 4.0, demonstrating practical efficacy and accuracy within this framework. [Display omitted] [ABSTRACT FROM AUTHOR]

Stabilizing piles are commonly used to effectively reinforce landslides and unstable slopes. However, the reinforcement mechanism of stabilizing piles, especially portal double-row (PDR) piles, remains poorly understood. The deformation characteristics and stabilizing mechanism of PDR piles were examined through physical model tests and numerical modeling by considering various embedded depths and interbedded weak and hard bedrock combinations. First, physical model tests were performed to study the effects of interbedded bedrock, orthogonal joints in the upper hard stratum, and embedded depths on the stabilizing mechanism. Second, six groups of numerical models based on the physical models were developed using the distinct element method. The results show that the bending moment and horizontal displacement of PDR piles increase in the presence of orthogonal joints and decrease with increasing embedded depth. The effects of crossbeam and hard bedrock percentage on the PDR pile deformation mechanism were then assessed. The results show that the crossbeam significantly affects the stabilizing PDR pile mechanism, while the effect of hard bedrock percentage is relevant to the embedded depth of PDR piles. The study provides some theoretical information for landslide prevention in areas with interbedded weak and hard bedrock. [ABSTRACT FROM AUTHOR]

Rainfall represents one of the most significant cause of landslide hazards. With runoff in the saturated zone of shallow soil considered, an improved Green–Ampt model was proposed to depict the rainfall infiltration process. Furthermore, a formula for calculating the depth of wetting front was derived, and the slope stability was evaluated accordingly. Finally, a formula for calculating the safety factor of multilayer slopes above different surfaces was obtained via the limit equilibrium method. An illustration is a multilayer colluvial slope in Guangdong Province of China, the results indicated that the downward speed of wetting front decreases gradually within the same layer with continuous rainfall but increases significantly when it extends to the interfaces between the soil layers. Safety factor of the slope decreases sharply at the initial stage of rainfall but then more slowly. Slope failure is more likely to occur along the first interface between the soil layers than along the surface of wetting front. The result from the proposed model is closer to the result of the physical model test than from the existed Green–Ampt model. The improved Green–Ampt model for multilayer slopes can accurately evaluate the infiltration process and related stability of multilayer slopes under rainfall. [ABSTRACT FROM AUTHOR]

Sporophytic pollen coat proteins (sPCPs) derived from the anther tapetum are deposited into pollen wall cavities and function in pollen–stigma interactions, pollen hydration, and environmental protection. In Arabidopsis, 13 highly abundant proteins have been identified in pollen coat, including seven major glycine-rich proteins GRP14, 16, 17, 18, 19, 20, and GRP–oleosin; two caleosin-related family proteins (AT1G23240 and AT1G23250); three lipase proteins EXL4, EXL5 and EXL6, and ATA27/BGLU20. Here, we show that GRP14, 17, 18, 19, and EXL4 and EXL6 fused with green fluorescent protein (GFP) are translated in the tapetum and then accumulate in the anther locule following tapetum degeneration. The expression of these sPCPs is dependent on two essential tapetum transcription factors, MALE STERILE188 (MS188) and MALE STERILITY 1 (MS1). The majority of sPCP genes are up-regulated within 30 h after MS1 induction and could be restored by MS1 expression driven by the MS188 promoter in ms188 , indicating that MS1 is sufficient to activate their expression; however, additional MS1 downstream factors appear to be required for high-level sPCP expression. Our ChIP, in vivo transactivation assay, and EMSA data indicate that MS188 directly activates MS1. Together, these results reveal a regulatory cascade whereby outer pollen wall formation is regulated by MS188 followed by synthesis of sPCPs controlled by MS1. [ABSTRACT FROM AUTHOR]

Pollen wall consists of several complex layers which form elaborate species-specific patterns. In Arabidopsis, the transcription factor ABORTED MICROSPORE (AMS) is a master regulator of exine formation, and another transcription factor, TRANSPOSABLE ELEMENT SILENCING VIA AT-HOOK (TEK), specifies formation of the nexine layer. However, knowledge regarding the temporal regulatory roles of TEK in pollen wall development is limited. Here, TEK-GFP driven by the AMS promoter was prematurely expressed in the tapetal nuclei, leading to complete male sterility in the pAMS:TEK-GFP (pat) transgenic lines with the wild-type background. Cytological observations in the pat anthers showed impaired callose synthesis and aberrant exine patterning. CALLOSE SYNTHASE5 (CalS5) is required for callose synthesis, and expression of CalS5 in pat plants was significantly reduced. We demonstrated that TEK negatively regulates CalS5 expression after the tetrad stage in wild-type anthers and further discovered that premature TEK-GFP in pat directly represses CalS5 expression through histone modification. Our findings show that TEK flexibly mediates its different functions via different temporal regulation, revealing that the temporal regulation of TEK is essential for exine patterning. Moreover, the result that the repression of CalS5 by TEK after the tetrad stage coincides with the timing of callose wall dissolution suggests that tapetum utilizes temporal regulation of genes to stop callose wall synthesis, which, together with the activation of callase activity, achieves microspore release and pollen wall patterning. Author summary: To develop into mature pollen grains, microspores require formation of the pollen wall. To date, pollen wall developmental events, including production and transportation of pollen wall components, synthesis and degradation of the callose wall, and deposition and demixing of primexine, have been studied in Arabidopsis, and a number of anther- or tapetum-specific genes involved in pollen wall formation have been uncovered. However, whether the specific expression patterns of these genes contribute to pollen wall development or patterning remains unclear. Here, we show that TEK, a transcription factor that specifies formation of nexine (the inner layer of the pollen wall exine), represses the expression of the callose synthase CalS5 after the tetrad stage, which accurately fits with the timing of callose wall dissolution causing microspore release. Moreover, we show that premature expression of TEK in the wild-type anthers disturbs callose wall synthesis and pollen wall patterning. This work reveals that a pollen wall regulator must be kept under a strict temporal control to perform its functions, and that these temporal controls are coordinated with other pollen wall developmental events to determine pollen wall formation and patterning. [ABSTRACT FROM AUTHOR]

[Display omitted] • SERS hybrid substrate with the sandwich structure was fabricated by a simple way. • Enhancement factors of up to 3.10 * 104 were achieved by adjusting the particle size. • Direct detection of trace amounts of pesticides on the surface of fruits is 10-9 g/ml. The overuse of mixed pesticides poses a threat to both the ecosystem and human health, yet general pesticide detection methods are complex in terms of steps, such as the need for pretreatment and cleaning. Surface-enhanced Raman scattering (SERS) has been used for real-life trace detection of residues due to its rapid detection and ultra-high sensitivity. Here, we prepared a novel Ti 3 C 2 Tx (MXene)-noble metal hybrid flexible substrate with a layer of MXene on top of flower-like Ag nanoparticles (AgNFs), and finally grew Au nanoparticles (AuNPs) by galvanic replacement and self-reduction reactions. The limit of detection (LOD) can be as low as 2 × 10-12 M by detecting 4-mercaptobenzoic acid (4MBA). For efficient sampling, transparent and flexible platform made of polydimethylsiloxane (PDMS) were used for the extraction and detection of thiabendazole (TBZ), thiram, methyl parathion (MP) and their mixtures. Notably, the lowest concentrations detected by swabbing on the tomato surface (3.7 ng/mL, 2.8 ng/mL) were lower than the EU maximum permissible limits of pesticides on raw fruits and vegetables (4.0 mg/L, 6.33 mg/mL). This high performance Ti 3 C 2 Tx-noble metal hybrid flexible substrate offers a great advantage in the trace detection of molecules. [ABSTRACT FROM AUTHOR]

The composite structure composed of GO and Ag has better sensing ability and is widely used as SERS substrates. However, there are few studies on the influence of external environment such as light on the stability of GO and Ag composite structure. In fact, GO can effectively prevent Ag from oxidation, so it is necessary to deeply study the mechanism of GO protection. In view of this, we prepare Ag microspheres on glass slides by one-step reduction method, and spin-coated with GO as surface enhanced Raman scattering (SERS) strips for the detection of organic molecules R6G. The detection limit is as low as 10−12 M. The linearity of the detection results is significantly corrected by using the GO characteristic peak as the internal standard (IS). The effects of xenon lamp simulate sunlight irradiation on the SERS performance of Ag substrate and Ag/GO Raman strips are investigated comparatively. We find that the Ag/GO composite structure can maintain good stability without the influence of light compared to the Ag substrate. We discuss the dynamic variation of Ag and Ag/GO substrates during the light exposure. Bacterial inhibition experiments further demonstrate the protective effect of GO on Ag. The conclusions of this paper have potential applications for improving the stability of SERS substrates. [Display omitted] [ABSTRACT FROM AUTHOR]

The sexine layer of pollen grain is mainly composed of sporopollenins. The sporophytic secretory tapetum is required for the biosynthesis of sporopollenin. Although several enzymes involved in sporopollenin biosynthesis have been reported, the regulatory mechanism of these enzymes in tapetal layer remains elusive. ABORTED MICROSPORES ( AMS) and MALE STERILE 188/ MYB103/ MYB80 ( MS188/ MYB103/ MYB80) are two tapetal cell-specific transcription factors required for pollen wall formation. AMS functions upstream of MS188. Here we report that AMS and MS188 target the CYP703A2 gene, which is involved in sporopollenin biosynthesis. We found that AMS and MS188 were localized in tapetum while CYP703A2 was localized in both tapetum and locule. Chromatin immunoprecipitation (Ch IP) showed that MS188 directly bound to the promoter of CYP703A2 and luciferase-inducible assay showed that MS188 activated the expression of CYP703A2. Yeast two-hybrid and electrophoretic mobility shift assays ( EMSAs) further demonstrated that MS188 complexed with AMS. The expression of CYP703A2 could be partially restored by the elevated levels of MS188 in the ams mutant. Therefore, our data reveal that MS188 coordinates with AMS to activate CYP703A2 in sporopollenin biosynthesis of plant tapetum. [ABSTRACT FROM AUTHOR]

Pesticides are often overused in production and life, which harms the environment and human health. However, the current tools for detecting pesticides are not effective enough due to lower flexibility and stability. With regards to this, we synthesized a flexible substrate of PDMS modified by MXene (Ti 3 C 2 Tx)/Ag. The MXene-noble metal composite substrate can detect 4-mercaptobenzoic acid (4MBA) at a low concentration of 1.0 × 10−11 M. Furthermore, MXene can inhibit the oxidation of Ag nanoparticles (NPs) and efficiently localize the molecules to be tested within the hot spots. In particular, the flexibility of the substrate enables the detection of trace amounts of thiabendazole (TBZ) by collecting samples directly from uneven surfaces such as fruits and vegetables. The substrate is also capable of detecting a mixture of TBZ and 4MBA simultaneously. Using intrinsic Raman peak of PDMS as the internal standard can eliminate the influence of environmental factors on the detection results, which makes the detection results more quantitative. The resultant noble metal-semiconductor substrates show great potential applications in food safety and environmental monitoring fields. [Display omitted] • Synthesis of a noble metal-semiconductor (MXene/Ag/PDMS) substrate by a quick two-step method. • The substrate has excellent flexibility and stability and the signal of 4MBA is still stable after ten days. • The substrate can detect trace (10−8 g/mL) TBZ on fruit surfaces. • The substrate can simultaneously detect the mixed solution of TBZ and 4MBA. [ABSTRACT FROM AUTHOR]

Abstract: Four sulfated heteropolysaccharide fractions (OJP-1, OJP-2, OJP-3 and OJP-4) were isolated and purified from the tuber of Ophiopogon japonicus by DEAE-Sepharose Fast Flow and Sepharose 6 Fast Flow column chromatography. OJP-1, the least sulfated product, was sulfated synthetically to OJP-1S. Their chemical–physical properties were determined by chemical methods, GC, FT-IR spectroscopy, and HPLC. The antioxidant and immunomodulation activities of these fractions were also investigated. The content of hexuronic acid and sulfate were decreased in the order OJP-4>OJP-3>OJP-2>OJP-1 and OJP-1S>OJP-4>OJP-3>OJP-2>OJP-1, respectively. In comparison with OJP-1, other polysaccharides showed stronger 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and hydroxyl radical scavenging activity. Five polysaccharides also exhibited remarkable macrophage-activating capability by the promotion of phagocytic capacity, energy metabolism rate, NO and interleukin-1 production. It was significantly different between five polysaccharides (P <0.01) and decreased in the order OJP-1S>OJP-4>OJP-3>OJP-2>OJP-1. Taken together, our results suggested that hexuronic acid and sulfate were effective indicators of antioxidant and immunomodulation activity of polysaccharide. [Copyright &y& Elsevier]

This study aimed at determining the effects of purified chondroitin sulfate (ChS) from pig laryngeal cartilage on the lipid and antioxidant metabolisms of male Sprague-Dawley rats that are fed a high-fat diet. Thirty-two male rats were divided into four groups and fed for 5 weeks on a standard diet, a high-fat diet or a high-fat diet plus ChS. It was demonstrated that the high-fat diet provoked lipid peroxidation and induced a severe depletion of lipoprotein lipase, hepatic lipidase, glutathione, catalase and superoxide dismutase levels. ChS was effective in reducing triglycerides, total cholesterol, low-density-lipid cholesterol and malondialdehyde levels elevated by the high-fat diet. In addition, ChS might reduce the risk of atherosclerosis, as high-density-lipid cholesterol, lipoprotein lipase, hepatic lipidase and the ratio of high-density-lipoprotein cholesterol to total cholesterol were significantly higher than in the high-fat-diet rats. ChS restored the endogenous antioxidants glutathione, catalase and superoxide dismutase. These results showed that ChS was potent in lipid-lowering and altering the antioxidative enzyme; however, excess ChS would disturb lipid profiles that went beyond the normal limits. [ABSTRACT FROM AUTHOR]

This study compared the free radical-scavenging properties of chondroitin sulfate (ChS) from pig laryngeal cartilage and its reduced or sulfonated derivatives. The binding behavior between Cu 2+ and ChS and its derivatives, and the interaction between superoxide radical and ChS were studied by fluorescence quenching, equilibrium dialysis, infrared spectra and thermal analysis. Purified ChS inhibited the generation of hydroxyl radical and scavenged superoxide radical in a concentration-dependent manner. Reduced ChS did not scavenge hydroxyl radical and superoxide radical. Sulfonated ChS had no hydroxyl radical scavenging activity but scavenged superoxide radical as strongly as purified ChS. ChS showed strong binding activity with Cu 2+ in deionized water but not in 0.01-M HCl. Both reduced ChS and sulfonated ChS did not exhibit such chelating behavior. The structural basis of hydroxyl radical inhibiting of ChS was attributed to a complex of the Cu 2+ with the carboxyl group of glucuronic acid residue. The reaction of superoxide radical with the sulfate ester and the carboxyl group may be the basis of superoxide radical scavenging activity of ChS. [ABSTRACT FROM AUTHOR]

Plant growth and mineral element accumulation in Brassica juncea var. crispifolia (crisped-leaf mustard) under exposure to lanthanum (La) and cadmium (Cd) were studied by employing a hydroponic experiment with a complete two-factorial design. Four levels of La (0.05–5.0 mg L -1 ) and two levels of Cd (1.0 and 10.0 mg L -1 ) were used in this experiment. Lanthanum did not improve plant growth in this experiment. Addition of La (≥ 1.0 mg L -1 ) or Cd (≥ 10 mg L -1 ) to the solution inhibited root elongation. Lanthanum treatments reduced accumulations of iron (Fe), manganese (Mn), and zinc (Zn) in roots, and Mn in shoots. Lanthanum at ≥ 1.0 mg L -1 limited the Cd translocation from roots to shoots and thus decreased the accumulation of Cd in shoots. Cadmium had no influence on La accumulations in roots, but inhibited the accumulation of La in shoots. The study results suggest that applications of rare earth elements in vegetables would be potentially risky to human health. [ABSTRACT FROM AUTHOR]

PANX2 forms large-pore channels mediating ATP release in response to physiological and pathological stimuli. Although PANX2 shows involvements in glioma genesis, the underlying mechanism remains unclear. PANX2 mRNA expression was analyzed via Oncomine and was confirmed via Gene Expression Profiling Interactive Analysis (GEPIA). The influence of PANX2 on overall survival (OS) of glioma was evaluated using LinkedOmics and further assessed through Cox regression analysis. The correlated genes with PANX2 acquired from LinkedOmics were validated through GEPIA and cBioPortal. Protein-protein interaction (PPI) of these genes was then obtained using Search Tool for the Retrieval of Interacting Genes (STRING) and Cytoscape with MCODE plug-in. All the PANX2-related genes underwent Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. The correlation between PANX2 and cancer immune infiltrates was evaluated via Tumor Immune Estimation Resource (TIMER). A higher expression of PANX2 only revealed a better OS in brain low grade glioma (LGG). PANX2-related genes in LGG functionally enriched in neuroactive ligand-receptor interaction, synaptic vesicle cycle, and calcium signaling. The hub genes from highest module of PPI were mainly linked to chemical synaptic transmission, plasma membrane, neuropeptide, and the pathway of neuroactive ligand-receptor interaction. Besides, PANX2 expression was negatively associated with infiltrating levels of macrophage, dendritic cells, and CD4+ T cells. This study demonstrated that PANX2 likely participated in LGG pathogenesis by affecting multiple molecular pathways and immune-related processes. PANX2 was associated with LGG prognosis and might become a promising therapeutic target of LGG. [ABSTRACT FROM AUTHOR]

Ling-Qui-Qi-Hua (LGQH) decoction, composed of Poria cocos (Schw.) Wolf, Cinnamomum cassia (L.) J. Presl, Paeonia veitchii Lynch, and Atractylodes macrocephala Koidz., is a compound formula derived from Ling-Gui-Zhu-Gan decoction recorded in the Treatise on Febrile and Miscellaneous. It has shown cardioprotective effects on patients or rats with heart failure with preserved ejection fraction (HFpEF). Nevertheless, the active ingredients of LGQH and its anti-fibrotic mechanism remain unknown. To determine the active ingredients in LGQH decoction and verify that LGQH decoction may inhibit left ventricular (LV) myocardial fibrosis in HFpEF rats by blocking the transforming growth factor-β1 (TGF-β1)/Smads signaling pathway from the perspective of animal experiments. First, liquid chromatography-mass spectrometry (LC-MS) technology was used to identify active components in the LGQH decoction. Secondly, a rat model of the metabolic syndrome-associated HFpEF phenotype was established and subsequently received LGQH intervention. The mRNA and protein expression of targets in the TGF-β1/Smads pathway were detected by quantitative real-time polymerase chain reaction and western blot analysis. Finally, molecular docking was conducted to examine the interactions between the active ingredients in the LGQH decoction and key proteins of the TGF-β1/Smads pathways. According to LC-MS analysis, the LGQH decoction contained 13 active ingredients. In animal experiments, LGQH attenuated LV hypertrophy, enlargement, and diastolic function in HEpEF rats. Mechanically, LGQH not only down-regulated TGF-β1, Smad2, Smad3, Smad4, α-SMA, Coll I, and Coll III mRNA expressions and TGF-β1, Smad2, Smad3, P-Smad2/Smad3, Smad4, α-SMA, and Coll I protein expressions, but also up-regulated Smad7 mRNA and protein expressions, which ultimately led to myocardial fibrosis. Furthermore, molecular docking confirmed that 13 active ingredients in the LGQH decoction have excellent binding activities to the critical targets of the TGF-β1/Smads pathway. LGQH is a modified herbal formulation with multiple active ingredients. It might alleviate LV remodeling and diastolic dysfunction and inhibit LV myocardial fibrosis by blocking TGF-β1/Smads pathways in HFpEF rats. [Display omitted] [ABSTRACT FROM AUTHOR]

Compound Qidan Formula is composed of traditional Chinese herbs and has a good curative effect in the clinical application of cardiovascular diseases such as heart failure. However, its potential molecular mechanisms of action remain highly unknown. To observe the effect of Compound Qidan Formula on cardiac function in rats with HFpEF induced by hypertension and diabetes mellitus, and to explore its mechanism from Ang Ⅱ/TGF-β1/Smads signaling pathway. A total of 50 SPF-grade spontaneously hypertensive rats (SHR) aged 14 weeks, fed with a high-fat and high-sucrose diet for 16 weeks, and after 2 weeks of a high-fat and high-sucrose diet, 1% streptozotocin (25 mg/kg body weight)was injected intraperitoneally to establish a rat model of HFpEF induced by hypertension and diabetes mellitus. After 8 weeks of intragastric administration, the changes in cardiac morphology and function were evaluated by echocardiography after anesthesia; the heart tissue was taken and embedded in paraffin for Masson staining, and the pathomorphological changes of left atrial tissue were observed under the optical microscope; the mRNA transcription levels of Ang Ⅱ, AT1R, TGF-β1, Smad2, Smad3, MMP-9 and TIMP-1in left atrial tissue of rats were detected by RT-PCR; and the protein expressions were detected by Western blot. Compared with the SHR-DM group, the QD-Low and QD-High groups significantly decreased the left atrial (LA) anteroposterior diameter and interventricular septal thickness (IVST) and improved the peak velocity of mitral valve blood flow in early diastolic period (E), maximum mitral valve blood flow in systolic period (A), mitral ring myocardial movement velocity in early diastolic period (e') and E/e' ratio; the QD-High group significantly improved the E/A ratio, left atrial ejection fraction (LAEF) and left ventricular ejection fraction(LVEF). Masson staining showed that compared with the WKY group, the SHR-DM group had obvious myocardial histomorphological lesions. Compared with the SHR-DM group, the Compound Qidan Formula groups significantly improved cardiomyocyte hypertrophy and disordered arrangement and inhibited myocardial fibrosis; the mRNA expression levels of Ang Ⅱ, AT1R, TGF-β1, Smad2, Smad3, and MMP-9 in myocardial tissue of Compound Qidan Formula groups were significantly decreased, and the mRNA expression level of TIMP-1 was significantly increased. The protein expression levels of Ang Ⅱ, TGF-β1, P-Smad2/3, and MMP-9 were significantly decreased. Compound Qidan Formula, composed of traditional Chinese herbs, can significantly improve cardiac function, improve atrial and ventricular remodeling, and prevent myocardial fibrosis and hypertrophy in rats with HFpEF induced by hypertension and diabetes mellitus. The mechanism may be related to regulating the Ang Ⅱ/TGF-β1/Smad2/3 signaling pathway. [Display omitted] • Cardiac remodeling caused by myocardial fibrosis plays an important role in heart failure with preserved ejection fraction. • Compound Qidan Formula improves cardiac function and remodeling in rats with heart failure with preserved ejection fraction. • Compound Qidan Formularegulates AngII/TGF-β1/Smad2/3 pathway to treat heart failure with preserved ejection fraction. [ABSTRACT FROM AUTHOR]

Two polysaccharides from Carthamus tinctorius L. (CTLP-1 and CTLP-2) were purified, and their structures were analyzed by physical and chemical testing. CTLP-1 had a mass of 5900 Da that was composed of arabinose, glucose, and galactose with a mass molar ratio of 6.7:4.2:1. The backbone of CTLP-1 was →1)-α-GalAp-(1→4)-α-Arap-(1→2)-α-Glup-(4→. CTLP-2 had a mass of 8200 Da that was composed of arabinose, glucose, and galactose with a mass molar ratio of 16.76:4.28:1. The backbone of CTLP-2 was →1)-α-Galp-(2,6 →1)-α-Arap-(4,6 →1)-α-Glup-(3→. Both of them exhibited a high reducing power, hydroxyl radical scavenging activity, DPPH radical scavenging activity and ABTS radical scavenging activity, moderate Fe2+ chelating activity and superoxide anion scavenging activity, implying that they might be potential antioxidants. [ABSTRACT FROM AUTHOR]

Double perovskite Ca 3 LiSbO 6 : x %Mn4+, y %Eu3+ far-red emitting phosphors with zero-thermal quenching properties as well as the sensitization effect of Eu3+ ions were reported. The Ca 3 LiSbO 6 :0.4%Mn4+ phosphor showed an emission intensity of 109 % at 423 K compared with that at 298 K. In addition, the emission intensity of Ca 3 LiSbO 6 :0.8%Mn4+, 4%Eu3+samples can be enhanced to about 1.25 times that of Ca 3 LiSbO 6 :0.4%Mn4+ due to the sensitization of Eu3+ ions. Meanwhile, the Ca 3 LiSbO 6 :0.8%Mn4+, 4%Eu3+ phosphor showed an internal quantum efficiency (IQE) of 78.9 % as compared with that of Ca 3 LiSbO 6 :0.4%Mn4+ (60.7 %), and the external quantum efficiency (EQE) also enhanced from 52.8 % to 68.5 % at the same time. Under the excitation of 365 nm light, the Ca 3 LiSbO 6 : x %Mn4+, y %Eu3+ samples display an emission peak at 698 nm, which is appropriate for the absorption of plant pigments including chlorophyll a , b and phytochrome of PFR. The result indicates that the Ca 3 LiSbO 6 : x %Mn4+, y %Eu3+ phosphors may have a potential in the application fields of pc-LEDs and indoor plant cultivations. [Display omitted] • Energy transfer process from Eu3+ to Mn4+ was observed in Ca 3 LiSbO 6 host. • Sensitization of Eu3+ ions results in a high IQE of 78.9 % for CLSO:0.8%Mn4+, 4%Eu3+ phosphor. • The CLSO:0.4%Mn4+ phosphor showed a zero thermal quenching performance with 109 % PL intensity maintained at 423 K. [ABSTRACT FROM AUTHOR]

During anther development, the transformation of the microspore into mature pollen occurs under the protection of first the tetrad wall and later the pollen wall. Mutations in genes involved in this wall transition often lead to microspore rupture and male sterility; some such mutants, such as the reversible male sterile (rvms) mutant, are thermo/photoperiod-sensitive genic male sterile (P/TGMS) lines. Previous studies have shown that slow development is a general mechanism of P/TGMS fertility restoration. In this study, we identified restorer of rvms-2 (res2), which is an allele of QUARTET 3 (QRT3) encoding a polygalacturonase that shows delayed degradation of the tetrad pectin wall. We found that MS188, a tapetum-specific transcription factor essential for pollen wall formation, can activate QRT3 expression for pectin wall degradation, indicating a non-cell-autonomous pathway involved in the regulation of the cell wall transition. Further assays showed that a delay in degradation of the tetrad pectin wall is responsible for the fertility restoration of rvms and other P/TGMS lines, whereas early expression of QRT3 eliminates low temperature restoration of rvms-2 fertility. Taken together, these results suggest a likely cellular mechanism of fertility restoration in P/TGMS lines, that is, slow development during the cell wall transition of P/TGMS microspores may reduce the requirement for their wall protection and thus support their development into functional pollens, leading to restored fertility. This work identified a restorer (res2) of the P/TGMS mutant rvms-2 ; res2 is an allele of QRT3 , which encodes a polygalacturonase that participates in tetrad pectin wall degradation. The authors showed that a delay in degradation of the tetrad pectin wall is responsible for fertility restoration of rvms and other P/TGMS lines, revealing a likely cellular mechanism of fertility restoration in P/TGMS lines. [ABSTRACT FROM AUTHOR]

[Display omitted] Using CALYPSO software, the calculations of Au n Br (n = 2–13) nanoclusters based on DFT show that Au 5 Br nanocluster with 2D-type triangle geometry has the strongest local stability and thus can be viewed as a new potential 2D-type nanomaterial. Interestingly, as shown below, the electron localization function (ELF) calculation shows that there are no regions with ELF values greater than 0.5 between atoms, implying no covalent interactions in Au 5 Br nanocluster. • Au 7 Br is the 2D to 3D structural transition point in Au n Br (n = 2–13) nanoclusters. • Au 5 Br nanocluster has the highest local stability with 2D-type triangle geometry. • The charges are transferred from Au atoms to Br atoms in Au n Br (n = 2–13) nanocluster. • The s-, p- and d- hybridization between the atomic orbitals of Br and Au creates a considerable energy gap in Au 5 Br nanocluster. A new potential relatively highly stable two-dimensional (2D) type naonomaterial of doped gold nanoclusters, Au 5 Br, is reported. The nanomaterial is obtained by searching bromine-doped neutral gold clusters through the CALYPSO software together with DFT method. The structural study of Au n Br (n = 2–13) nanoclusters indicates that the geometrical transition size of the lowest energy structures from 2D to three-dimensional (3D) is Au 6 Br, and the 3D structures of Au n Br (n = 7–13) are all based on the multilayer pyramid-type. The research on the relative stability of the ground state of the Au n Br (n = 2–13) clusters reveals that these clusters are odd-sized number stable. Interestingly, the most special one is Au 5 Br with 2D triangle geometry, which has the strongest local stability and can be used as a candidate for magic cluster. The calculations of the natural charge population (NCP) in all the lowest energy clusters show that all bromine atoms are negatively charged. Polarization analysis strongly suggests that Au 4 Br nanocluster's nonlinear optic properties is probably particular better than other nanoclusters. Finally, in order to further understand the high stability properties of Au 5 Br nanocluster, its molecular orbitals (MOs), electronic localization function (ELF), infrared (IR) and Raman spectra are also studied in detail. [ABSTRACT FROM AUTHOR]

Natural rock often suffers from cyclic wetting–drying involving different water types, and the resulting deterioration may differ from laboratory tests using distilled water or salt solutions. An inappropriate estimation of this deterioration effect may lead to fatal geological hazards and engineering failures. A multiscale study is conducted to investigate the physical and mechanical features of sandstone in Three Gorges Reservoir region (TGR sandstone) subjected to cyclic wetting–drying of Yangtze River water. During this study, three types of water, i.e., Yangtze River water, ionized water having similar ion compositions as the Yangtze River water, and distilled water, are used for comparison. The results show that the multiscale physical properties including mineral compositions (especially calcite and albite), micro-pore parameters, computed tomography values, and macro-mechanical parameters (i.e., Young's modulus, uniaxial compression strength and tensile strength) are remarkably altered during the cyclic wetting–drying process. Significant correlations are found between these numerous multiscale properties. The results indicate that changes of mineral compositions and microstructure are the primary reasons for the deterioration of sandstone strength. The deterioration effect of distilled water on TGR sandstone is the least, while the effect of ionized water is the greatest, and that of river water being intermediate. These differences are ascribed to different chemical interactions, together with possible microorganism effects for river water, as microorganisms in river water potentially weaken the deterioration of cyclic wetting–drying of river water. In situ water is recommended for studying how rock properties are affected by water–rock interactions in real settings. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow spherical vaterite CaCO 3 (HSVC) was prepared via spray-bubble template method. • The influence of different conditions on HSVC synthesis was investigated. • HSVC exhibited high enzyme loading capacity. • Immobilized papain exhibited excellent pH, temperature stability and reusability. • The HSVC preparation and papain immobilization were studied via MDS. Calcium carbonate (CaCO 3) possesses unique advantages as a carrier , however, some critical issues need to be addressed, such as low productivity, irregular structures, and weak adsorption ability. Herein, hollow spherical vaterite CaCO 3 (HSVC) was synthesized in an improved spray apparatus with high mass transfer using carbon dioxide (CO 2) as a template and was in turn applied for papain immobilization. Results revealed that HSVC can be prepared cleanly and efficiently with a regular spherical morphology having a surface area of 17.03 m2·g−1 and immobilization amount of 1068 mg·g−1 for papain. Interestingly, the pH stability, temperature stability and reusability of papain were dramatically improved after immobilization by HSVC. Molecular dynamics simulation (MDS) disclosed that the formation of CO 3 2– and Ca2+ ion pairs was the key factor for the preparation of HSVC and the binding energy (BE) between amino acid molecules and vaterite (1 1 0) facilitated the ultra-high adsorption of papain. The decrease in BE of system after immobilization facilitated high catalytic capacity of the immobilized papain. The prepared HSVC exhibits promising prospects in enzymes immobilization based applications. [ABSTRACT FROM AUTHOR]

Highlights • The plant polyketide synthase is required for the sporopollenin precursor biosynthesis. • Knockout of the rice OsPKS1 leads to abnormal bacula deposition and ubisch body structures for sexine formation. • This protein was preferentially localized to the ER in tapetal cells during microspore development. • The function of polyketide synthase in sporopollenin synthesis pathway are conserved in rice and Arabidopsis. Abstract The sporopollenin precursors, as a general constituent of sexine, are synthesized in the tapetum and deposited on the pollen surface after transportation and processing. The polyketide synthase condenses the acyl-CoA into a hydroxyalkyl α-pyrone, which is predicted to be a component of the sporopollenin precursors. In this study, we found that the rice POLYKETIDE SYNTHASE 1 (OsPKS1) was the orthologue of Arabidopsis POLYKETIDE SYNTHASE A/LESS ADHESIVE POLLEN 6 (PKSA/LAP6) through sequence alignment. The OsPKS1 knockout mutants obtained by Crispr-Cas9-mediated editing exhibited a complete male sterile phenotype. Cytological observations revealed that abnormal bacula deposition and ubisch body structures for sexine formation led to pollen rupture in ospks1. The expression analysis showed that the OsPKS1 was highly expressed in tapetal cells and anther locules from stage 9 to stage 11 during anther development in rice. Subcellular localization demonstrated that the OsPKS1 protein was preferentially localized to the ER. The genomic sequence of OsPKS1 driven by the PKSA/LAP6 promoter restored the sexine pattern of Arabidopsis pksa/lap6. These results indicated that OsPKS1 is required for sexine layer formation in rice and functionally conserved in the sporopollenin synthesis pathway. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) ultrafiltration membranes modified by montmorillonite (MMT) nanoparticles were fabricated via phase inversion method. The influences of MMT nanoparticles on the structure and performances of the membranes were investigated by water contact angle measurement, porosity and mean pore size measurement, scanning electron microscopy (SEM) analysis, atomic force microscopy (AFM) analysis, thermogravimetric analysis (TGA), filtration and fouling experiments. The results revealed that the hydrophilicity of the composite membrane surface was improved significantly, and the porosity and mean pore size increased after MMT nanoparticles were added. When the mass fraction of MMT nanoparticle was 0.2%, the surface of the composite membrane surface was smoother than that of pure membrane, the size of finger-like cavities increased, the thermal stability increased, the pure water flux reached the maximum value with 450 L/(m² ⋅ h), the flux recovery ratio reached up to 95.1 % and the antifouling property was the best. While excessive dosage of MMT nanoparticles will significantly increase the viscosity of casting solution, and make the aggregation of nanoparticles, resulting in the poor performance of the PLA membrane. [ABSTRACT FROM AUTHOR]

The trace elements in the public drinking water have a duality: on the one hand, trace elements play an important role in maintaining human metabolism; on the other hand, high trace elements levels lead to significant health risks. To determine the impacts of trace elements in the public drinking water on physical health in China, water samples were collected from 314 Chinese cities to analyze the concentrations and spatial distributions of trace elements on a national scale. On this basis, the non-carcinogenic health risk assessments and the nutrient-based scores of trace elements (NSTEs) were applied to evaluate the public drinking water quality in terms of safety and nutrition. Most of the water samples were weakly alkaline: pH values fell in the range of 6.62–8.54, with a mean of 7.80. The results indicated that Sr and F− had the highest concentrations in public drinking water, with averages of 0.3604 mg/L and 0.2351 mg/L, respectively. Moreover, hazard index (HI) values in different regions followed the order: northwest China (NWC) > northern China (NC) > Qinghai-Tibetan Plateau (QT) > southern China (SC). The percentages of water samples with HI > 1 in SC, NC, NWC, and QT were 5.49%, 16.82%, 25.81%, and 16.67%, respectively, indicating that the public drinking water in some cities had significant non-carcinogenic health risks. In addition, the intakes of Mn, Fe, Cu, and Rb through public drinking water made negligible contributions to their recommended nutrient intakes. In contrast, trace elements like Sr, F, B, Li, Mo, etc., contributed a lot. The NSTEs in NWC and most parts of NC were relatively high with averages of 8.0300 and 11.2082, respectively; however, the NSTEs in SC and the northeast part of NC were low with averages of 3.3284 and 5.2106, respectively. The results from this study provide a reference for establishing the public drinking water standards and improving drinking water quality. [Display omitted] • Significant differences in the distribution of trace elements in China exist. • The public drinking water in 37 cities has obvious non-carcinogenic health risks. • Intakes of Sr, F−, B, Li, Mo from public drinking water are important for health. • Intakes of Mn, Fe and Cu through drinking water can be ignored. • The nutrient-based scores of trace elements are high in NC and NWC but low in SC. [ABSTRACT FROM AUTHOR]

During anther development, the tapetum provides materials and nutrients for pollen development. In Arabidopsis, several transcription factors have been identified to form a genetic pathway (DYT1-TDF1-AMS-MS188-MS1) for tapetal development and function. DEFECTIVE in TAPETAL DEVELOPMENT and FUNCTION1 (TDF1) is a member of the R2R3 MYB family and is essential for early tapetum development in Arabidopsis. Here, we characterized an ortholog of Arabidopsis TDF1 in rice, OsTDF1 (LOC_Os03g18480). OsTDF1 shares 69 % amino acid sequence identity with AtTDF1 in the putative MYB domain near the N-terminal region. RT-PCR and in situ hybridization show that OsTDF1 is specifically expressed in tapetal cells of rice anthers. The expression of OsTDF1 in Arabidopsis tdf1 mutant restores its fertility, suggesting that this homolog can fulfill the normal function of TDF1 in Arabidopsis. The ostdf1 knockout mutant exhibits a male-sterile phenotype. Its tapetal cells exhibit a vacuolated and hypertrophic phenotype similar to that of Arabidopsis tdf1 mutants. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assays revealed OsTDF1 acts as an essential regulator for tapetum programmed cell death. The qRT-PCR analysis revealed that OsTDF1 acts downstream of UDT1 and upstream of TDR, EAT1, OsMYB103 and PTC1 in rice, suggesting that the genetic pathway for tapetum development is generally conserved between rice and Arabidopsis. [ABSTRACT FROM AUTHOR]

The southwest karst area is considered to have the most vulnerable groundwater environment in China. Groundwater quality is an important factor restricting sustainable economic development. In this study, traditional water chemistry method, water quality index (WQI), and hazard index (HI) were applied to comparatively analyze the hydrochemical characteristics of groundwater and the water quality in the exposed karst region (EKR) and buried karst region (BKR) in Bama, a typical karst area in southwest China. Generally, the main water type was Ca/Mg–HCO 3. Due to the predominance of dissolution of carbonate rocks in EKR and silicate rocks in BKR, higher total dissolved solids (TDS), Ca and HCO 3 − concentrations, and lower H 2 SiO 3 content were detected in groundwater in EKR compared with BKR. As affected by weathering of rocks such as lead-zinc ore, the maximum concentrations of Zn and Sr were 11.23 mg/L and 13.30 mg/L, showing that mineral water resources are widely distributed in Bama. The ion ratios and isotope abundances (δD and δ18O) in groundwater samples indicated stronger evaporation and rock-water interaction in EKR than BKR. Human activities exerted a more significant influence on the water quality in EKR compared to BKR. The mean WQI value also suggested that the groundwater quality was better in BKR (9.56) than EKR (12.17). Although 95.7% of the water samples in the study area were classified as excellent based on their WQI values, 4.3% of the water samples still had significant health risks (HI > 1) due to the high Sb, Zn, As, and Sr concentrations. It is recommended to reduce anthropogenic pollution in EKR and develop a plan for clean production of mineral water industry according to local conditions, which will help the sustainable development of the local economy. [Display omitted] • Groundwater hydrochemistry in exposed and buried karst regions is totally different. • Aquatic environment in exposed karst regions is more sensitive than buried ones. • Sb, As, and Zn are the main trace elements which may pose non-carcinogenic risks. • Groundwater quality assessment contributes to sustainable water management. [ABSTRACT FROM AUTHOR]

Abstract: In case hazardous contaminants are suddenly released indoors, the prompt and proper emergency responses are critical to protect occupants. This paper aims to provide a framework for determining the optimal combination of ventilation and evacuation strategies by considering the uncertainty of source locations. The certainty of source locations is classified as complete certainty, incomplete certainty, and complete uncertainty to cover all the possible situations. According to this classification, three types of decision analysis models are presented. A new concept, efficiency factor of contaminant source (EFCS), is incorporated in these models to evaluate the payoffs of the ventilation and evacuation strategies. A procedure of decision-making based on these models is proposed and demonstrated by numerical studies of one hundred scenarios with ten ventilation modes, two evacuation modes, and five source locations. The results show that the models can be useful to direct the decision analysis of both the ventilation and evacuation strategies. In addition, the certainty of the source locations has an important effect on the outcomes of the decision-making. [Copyright &y& Elsevier]