Physi-Chemical Property Research of Polysaccharides from Pomegranate Flowers

Pomegranate flowers as row materials were used for extraction of polysaccharides by water-extraction and alcohol-precipitation method. After purification, the physical and chemical properties, structure, monosaccharide composition and molecular weight were studied. The results showed that the polysaccharides from pomegranate flowers mainly contained two kinds of water soluble acidic polysaccharides, and monosaccharide composition were arabinose and galactose, both contained hydroxyl, carboxyl, amino, hydroxyl radical, sulfate, beta glycosidic bond and alpha glycosidic bond structure. The molecular weight of PP1 and PP2 were 6.16 × 104 (±6.6%) and 9.01 × 104 (±3.2%), respectively. The results of this study laid the foundation for further development and application of polysaccharides from pomegranate flowers.

Effects of Hydrogen on Storage Decay and Antioxidant System of Strawberry

In order to determine whether hydrogen acts as antioxidant in plant tissues,fresh strawberry was put in sealed bags filled with 4%H_(2) atmosphere(T_(1)),100%H_(2)(T_(2)),100%air(CK_(1))and 100%N_(2)(CK_(2)),respectively.The decay rate,soluble solids content(SSC),titration acid(TA),ascorbic acid(Vc),MDA content,SOD and antioxidant activity in strawberry were measured during storage periods.Results showed that the decay rate and MDA content were reduced in H_(2) treatments;and H_(2) treatments gave lower level of TA and higher SSC,Vc,SOD and antioxidant activity,and 100%H_(2) had the best effect.It is suggested that strawberry fruit quality,antioxidant system and membrane lipid peroxidation were affected by H_(2) treatments.

Ectopic expression of AANAT or HIOMT improves melatonin production and enhances UV-B tolerance in transgenic apple plants

Melatonin is involved in plant responses to various environmental stresses.Although many studies have demonstrated that the tolerance of plants to stress is improved by exogenous melatonin,the role of endogenous melatonin metabolism in the response of apples to UV-B stress remains unclear.Here,the human melatonin biosynthesis-related enzyme genes AANAT or HIOMT were transformed into‘GL-3'apple,and the transgenic lines were treated with UV-B stress.The ectopic expression of AANAT or HIOMT significantly increased the melatonin content in apples.After UV-B stress,the tolerance of apple lines with ectopic expression of AANAT or HIOMT was markedly improved.The decrease in chlorophyll fluorescence,the generation of reactive oxygen species and the shrinkage of stomata caused by UV-B stress were alleviated by AANAT or HIOMT ectopic expression.In addition,the total phenolic content was markedly increased in the transgenic lines compared with the WT(wild type).The increase in phenolic compounds was related to the increase in benzoic acid,hydroxycinnamic acid,dihydrochalcones and flavanols,among which increases in chlorogenic acid,phloridzin and procyanidin B1 content were most prominent.Furthermore,the transgenic lines did not only promote the expression of genes related to phenolic synthesis under UV-B stress,but they also increased the accumulation of phenolic compounds by inhibiting the expression of MdPPO and MdPOD related to phenolic degradation.In summary,our results demonstrate that AANAT-or HIOMT-mediated melatonin synthesis improved the tolerance of apples to UV-B stress,mainly by scavenging reactive oxygen species,increasing photosynthetic capacity and increasing total phenolic content.

Enhancing building pattern recognition through multi-scale data and knowledge graph:a case study of C-shaped patterns

Building pattern recognition is important for understanding urban forms,automating map generalization,and visualizing 3D city models.However,current approaches based on object-independent methods have limitations in capturing all visually aware patterns due to the part-based nature of human vision.Moreover,these approaches also suffer from inefficiencies when applying proximity graph models.To address these limitations,we propose a framework that leverages multi-scale data and a knowledge graph,focusing on recognizing C-shaped building patterns.We first employ a specialized knowledge graph to represent the relationships between buildings within and across various scales.Subsequently,we convert the rules for C-shaped pattern recognition and enhancement into query conditions,where the enhancement refers to using patterns recognized at one scale to enhance pattern recognition at other scales.Finally,rule-based reasoning is applied within the constructed knowledge graph to recognize and enrich C-shaped building patterns.We verify the effectiveness of our method using multi-scale data with three levels of detail(LODs)collected from AMap,and our method achieves a higher recall rate of 26.4%for LOD1,20.0%for LOD2,and 9.1%for LOD3 compared to existing methods with similar precisionrates.We,also achieve recognition efficiency improvements of 0.91,1.37,and 9.35 times,respectively.

Multi-functional polyethersulfone nanofibrous membranes with ultra-high adsorption capacity and ultra-fast removal rates for dyes and bacteria

The adsorption technology has been widely applied in water remediation for contamination removal of dyes and bacteria,by virtue of the advantages of adsorption technology including high efficiency,energy conservation and ease of operation.Simultaneous removal of dyes and bacteria has been realized by some reported materials,but to achieve satisfactory adsorption amounts and rates remain an unmet goal for decades.Herein,a poly(methacrylatoethyl trimethyl ammonium chloride-co-methyl methacrylate)copolymer was synthesized,and then blended with polyethersulfone for the fabrication of nanofibrous membranes via electrospinning for the use of fast and massive removal of dyes and bacteria.Owing to the introduction of abundant quaternary ammonium groups,the maximum adsorption amount for methyl orange was up to 909.8 mg g^(-1).In addition,the modified nanofibrous membranes showed good recyclability,broad applications in severe environments,selective adsorption ability,and excellent dynamic removal performance.Especially,thanks to the abundant functional groups,the membranes showed fast adsorption ability for bacteria through electrostatic interaction.It should be noted that the clearance ratio for Staphylococcus aureus or Escherichia coli by 6 min of static adsorption could reach 93%or 90%for each.Additionally,dynamic removal ratio via filtration with the nanofibrous membranes could reach 99.7%for Staphylococcus aureus or 98.7%for Escherichia coli in 90 s.Therefore,the proposed approach towards the quaternary ammonium modified polyethersulfone nanofibrous membranes creates a new route for ultra-high adsorption capacity and ultra-fast removal rates for dyes and bacteria in water remediation.

Selective potassium uptake via biocompatible zeolite–polymer hybrid microbeads as promising binders for hyperkalemia

Patients with chronic kidney disease are at high risk of hyperkalemia that is associated with various lifethreatening complications.Treatments primarily rely on orally administered potassium binding agents,along with low curative effects and various side effects.Herein,direct serum potassium uptake was realized via zeolite–heparin-mimicking-polymer hybrid microbeads.The preparation process involved the synthesis of the heparin-mimicking polymer via the in situ cross-linking polymerization of acrylic acid and N-vinylpyrrolidone in polyethersulfone solution,the fabrication of microbeads via zeolite-mixing,electro-spraying and phase-inversion,and the subsequent aqueous-phase modifications based on ion-exchange and metal-leaching.An ultra-high(about 88%)amount of zeolite could be incorporated and well locked inside the polymer matrix.Potassium uptake capability was verified in water,normal saline and human serum,showing high selectivity and fast adsorption.The microbeads exhibited satisfying blood compatibility,negligible hemolysis ratio,prolonged clotting time,inhibited contact activation,and enhanced antifouling property toward serum proteins and cells.The proposed approach toward zeolite–heparin-mimicking-polymer hybrid microbeads provided a cheap,efficient and safe treatment protocol of hyperkalemia for the high-risk patients.

Alloyed nanostructures integrated metal-phenolic nanoplatform for synergistic wound disinfection and revascularization

New materials for combating bacteria-caused infection and promoting the formation of microvascular networks during wound healing are of vital importance.Although antibiotics can be used to prevent infection,treatments that can disinfect and accelerate wound healing are scarce.Herein,we engineer a coating that is both highly compatible with current wound dressing substrates and capable of simultaneously disinfecting and revascularizing wounds using a metal-phenolic nanoplatform containing an alloyed nanostructured architecture(Ag@Cu-MPNNC).The alloyed nanostructure is formed by the spontaneous co-reduction and catalytic disproportionation reaction of multiple metal ions on a foundation metal-phenolic supramolecular layer.This synergistic presence of metals greatly improves the antibacterial activity against both Gram-negative and Gram-positive pathogenic bacteria,while demonstrating negligible cytotoxicity to normal tissue.In infected rat models,the Ag@Cu-MPNNC could kill bacteria efficiently,promoting revascularization and accelerate wound closure with no adverse side effects in infected in vivo models.In other words,this material acts as a combination therapy by inhibiting bacterial invasion and modulating bio-nano interactions in the wound.