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Circular single-stranded DNA (ssDNA) viruses have been rarely found in fungi, and the evolutionary and ecological relationships among ssDNA viruses infecting fungi and other organisms remain unclear. In this study, a novel circular ssDNA virus, tentatively named Diaporthe sojae circular DNA virus 1 (DsCDV1), was identified in the phytopathogenic fungus Diaporthe sojae isolated from pear trees. DsCDV1 has a monopartite genome (3185 nt in size) encapsidated in isometric virions (21–26 nm in diameter). The genome comprises seven putative open reading frames encoding a discrete replicase (Rep) split by an intergenic region, a putative capsid protein (CP), several proteins of unknown function (P1–P4), and a long intergenic region. Notably, the two split parts of DsCDV1 Rep share high identities with the Reps of Geminiviridae and Genomoviridae , respectively, indicating an evolutionary linkage with both families. Phylogenetic analysis based on Rep or CP sequences placed DsCDV1 in a unique cluster, supporting the establishment of a new family, tentatively named Gegemycoviridae , intermediate to both families. DsCDV1 significantly attenuates fungal growth and nearly erases fungal virulence when transfected into the host fungus. Remarkably, DsCDV1 can systematically infect tobacco and pear seedlings, providing broad-spectrum resistance to fungal diseases. Subcellular localization analysis revealed that DsCDV1 P3 is systematically localized in the plasmodesmata, while its expression in trans- complementation experiments could restore systematic infection of a movement-deficient plant virus, suggesting that P3 is a movement protein. DsCDV1 exhibits unique molecular and biological traits not observed in other ssDNA viruses, serving as a link between fungal and plant ssDNA viruses and presenting an evolutionary connection between ssDNA viruses and fungi. These findings contribute to expanding our understanding of ssDNA virus diversity and evolution, offering potential biocontrol applications for managing crucial plant diseases. A novel circular single-stranded DNA (ssDNA) virus, tentatively named Diaporthe sojae circular DNA virus 1 (DsCDV1), was identified in a phytopathogenic fungus. DsCDV1 represents evolutionary and ecological links between fungal and plant ssDNA viruses, supporting the establishment of a new family. Moreover, DsCDV1 encodes a movement protein and can systemically infect plants to confer broad-spectrum fungal resistance. [ABSTRACT FROM AUTHOR]

A new model which we called time driven model for option pricing is proposed. In this model, the price of underlying asset is driven by different random driving source in different time interval. Explicit option pricing formulas for the European call option are obtained by using the Mellin transform. Moreover, some numerical illustrations are given by computing European call option prices. [ABSTRACT FROM AUTHOR]

Chromosome specimens of sugarcane, Erianthus fulvus and their progenies were prepared with wall degradation hypotonic method to analyze the karyotypes of parents and F1, F2 hybrids. The results showed that most chromosomes of experimental materials are median region (m) chromosomes, while only a small amount of chromosomes are submedian (sm) chromosomes. The karyotype of YAU04/102 belongs to 2C type, while other materials belong to 2B type. In addition, the karyotypes of hybrids are asymmetrical and the chromosomes of hybrids show an evolutionary trend compared with parental chromosomes. [ABSTRACT FROM AUTHOR]

Poly(ether carbonate)s (PPCs) with carbonate unit (CU) content ranging from 57.8 to 97.1% and number average molecular weight ( Mn) around 100 kg/mol were conveniently prepared via copolymerization of CO2 and propylene oxide under combinatorial catalyst of rare earth ternary (RET) complex and double metal cyanide (DMC) complex. Enhancement of catalytic activity and reduction of propylene carbonate byproduct were realized due to synergetic effect of the two metal catalysts, where DMC can be activated in the presence of RET. Solubility fractionation confirmed that the obtained PPCs were copolymers, not physical blends of each polymer. Thermal performances of the PPCs were closely related to their CU content, their glass transition temperatures ( Tg) were tunable in the range of 6.7-36.3 °C, which decreased with decreasing CU content, while their thermal stabilities were enhanced significantly, an increase of 50.5 °C in 50% weight loss temperature was observed when CU content decreased from 97.1 to 57.8%. Both shear storage modulus and complex viscosity increased with increasing CU content, which became more obvious at lower frequency, featuring well with the CU content in the PPCs. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Aliphatic poly(urethane-amine) (PUA) was synthesized from copolymerization of CO2 and 2-methylaziridine (MAZ) using Y(CCl3COO)3-ZnEt2-glycerine coordination catalyst, the urethane content of PUA was over 80%, and its yield could reach 90%. PUA with molecular weight as high as 31.0 kg/mol was obtained when the copolymerization reaction was carried out in N, N-dimethylacetamide (DMAc), mainly due to the good solubility of PUA in DMAc. PUA exhibited reversible thermo-responsive property in deionized water, and the lower critical solution temperature (LCST) was highly sensitive to its urethane content and molecular weight, which was observed in a broad window from 37 to 90 °C. Furthermore, the phase transition behavior could also be controlled by change of pH value. When the pH value of the PUA aqueous solution changed from 9.2 to 13, the LCST value of the solution decreased from 48.4 °C to 30 °C. Therefore, the PUA showed thermo- and pH- dual responsive performance in water. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

Abstract: A new approach for the synthesis of polyaniline nanofibers under pseudo-high dilute conditions in aqueous system has been developed. High yield nanoscale polyaniline fibers with 18–110nm in diameter are readily prepared by a high aniline concentration 0.4M oxidation polymerization using ammonium persulfate (APS) as an oxidant in the presence of hydrochloric acid (HCl), perchloric acid (HClO4), (1S)-(+)-10-camphorsulfonic acid (CSA), acidic phosphate PAEG120 (PA120) and sulfuric acid (H2SO4) as the dopants. The novel pathway always produces polyaniline nanofibers of tunable diameters, high conductivity (from 100 to 101 S/cm) and crystallinity. [Copyright &y& Elsevier]

Abstract: Aqueous conducting polyaniline dispersion was prepared employing acidic phosphate ester bearing hydrophilic ethylene glycol segment as dopant, and conducting film with electrical conductivity of 25S/cm was obtained from the dispersion. Ordered self-assembly lamellar structure with interlamellar distance of 1.2nm was observed in the film, which consisted of alternating layers of rigid polyaniline chain and flexible phosphate ester side chains, where the phosphate side chain layer was separated by two rigid polyaniline layers. The lamellar structure leading to high conducting film was formed due to the confinement of polyaniline chain by crystallizable phosphate side chain, since the electrical conductivity decreased by four orders of magnitude once the dopant side chain crystalline was destroyed. The crystallizable side chain forced lamellar structure is expected to be a new chance for highly conducting polyaniline. [Copyright &y& Elsevier]

Abstract: In order to improve the mechanical performance and water resistance of water-borne conducting polyaniline film, conducting polyaniline/polyurethane–silica hybrid film was prepared in aqueous solution employing silanol-terminated polyurethane and methyltriethoxysilane as sol–gel precursors. The hybrid film showed surface resistivity of 108 Ω even though the conducting polyaniline loading was only 10wt% (or 1.5wt% of polyaniline), and the mechanical performance as well as water resistance was significantly improved, making it suitable for antistatic application. Therefore, a practical route to water-borne processing of conducting polyaniline is disclosed. [Copyright &y& Elsevier]

Abstract: The electroactivity of polyaniline was extended to pH=14 alkaline media by preparation of a novel electrostatic interaction conductive hybrid from water-borne conductive polyaniline and silica network containing carboxyl groups via sol–gel process. In addition, the obtained conductive polyaniline hybrid film displayed very low conductivity threshold percolation and demonstrated excellent stability upon cycling. [Copyright &y& Elsevier]

Abstract: Ferrocenesulfonic acid (FSA) was oxidized by iodine (I2) and then used as dopant for polyaniline emeraldine base. The resulted polyaniline showed an electrical conductivity of 4.50×10−2 S/cm and a ferromagnetic interaction with a positive Weiss constant of 15K, the magnetic behavior is attributed to the ferromagnetic coupling between ferrocenium cations in the counter-ions along the polyaniline chain. [Copyright &y& Elsevier]

Abstract: Conducting polyaniline with electrical conductivity of 2.34×10−1 Scm−1 was obtained using ferrocenesulfonic acid as dopant. After the ferrocenesulfonic acid was oxidized with FeCl3, though the electrical conductivity of the doped polyaniline decreased by 1–2 orders of magnitude, the magnetic susceptibility (χ) increased with the increase of the oxidation degree of ferrocenesulfonic acid. EPR spectra showed not only a signal with a g value of around 2, but also a so-called half-field signal with a g value of about 4 even at room temperature. Coexistence of ferromagnetic intrachain interactions and antiferromagnetic interchain interactions in the materials has been suggested. [Copyright &y& Elsevier]

Abstract: Poly(propylene carbonate) (PPC) with number average molecular weight (M n) higher than 200kg/mol was prepared via the terpolymerization of carbon dioxide, propylene oxide and diepoxide using Y(CCl3OO)3–ZnEt2–glycerine coordination catalyst. When equimolar ZnEt2 and diepoxide were used, double propagation active species were generated in situ by nucleophilic attack of metal alkoxide on diepoxide, leading to PPC of doubled M n value. The molecular weight of PPC has dramatic influence on its thermal and mechanical performances. PPC with M n of 227kg/mol showed modulus of 6900MPa, while the modulus of PPC with M n of 109kg/mol was only 4300MPa. Moreover, when M n increased from 109 to 227kg/mol, a 37°C increase of the onset degradation temperature was observed. [Copyright &y& Elsevier]

Abstract: Monodisperse oligo[(1,4-phenyleneethynylene)-alt-(2,5-thiopheneethynylene)]s, new candidates for molecular wires, were rapidly synthesized via an iterative divergent/convergent doubling strategy in solution as well as on Merrifield''s resin. [Copyright &y& Elsevier]

The synthesis of monodisperse oligo[(1,4-phenyleneethynylene)-alt-(2,5-thioph-eneethynylene)]s using an iterative divergent/convergent doubling strategy based on Sonogashira coupling reaction was presented. [ABSTRACT FROM AUTHOR]

Copolymerization of carbon dioxide and propylene oxide was carried out employing (RC6H4COO)3Y/glycerin/ZnEt2 (R=–H, –CH3, –NO2, –OH) ternary catalyst systems. The feature of yttrium carboxylates (ligand, substituent and its position on the aromatic ring) is of great importance in the final copolymerization. Appropriate design of substituent and position of the ligand in benzoate-based yttrium complex can adjust the microstructure of aliphatic polycarbonate in a moderate degree, where the head-to-tail linkage in the copolymer is adjustable from 68.4 to 75.4%. The steric factor of the ligand in the yttrium complex is crucial for the molecular weight distribution of the copolymer, probably due to the fact that the substituent at 2 and 4-position would disturb the coordination or insertion of the monomer, lead the copolymer with broad molecular distribution. Based on the study of ultraviolet–visible spectra of the ternary catalyst in various solvents, it seems that the absorption band at 240–255 nm be closely related to the active species of the rare earth ternary catalysts. [Copyright &y& Elsevier]

Comprehensive Summary Converting CO2 into valuable chemicals is an effective means to alleviate environmental pressure and the depletion of oil resources. Among them, polymers derived from the copolymerization of PO and CO2 have been widely studied because of their excellent properties. To meet the expansion of the application range of CO2‐based polymers, regulation of the CU in the polymer is imperative. Based on the understanding of the relationship between catalyst synergy and structure, we designed a new generation of polyester‐based polymeric catalysts APEPC‐R and RPEPC‐N with discretely distributed active centers to achieve the synthesis of CO2‐based polymers with regulated CU (from 50% to 90%). The discrete arrangement of catalyst active centers was demonstrated by 1H NMR and UV‐vis characterization. Benefiting from multi‐site synergy, high molecular weight (Mn > 100 kg/mol) CO2‐based copolymers with CU among 50%—90% were successfully synthesized and their properties were firstly investigated. This work not only contributes to enriching the scope of the application of CO2‐based copolymers but also provides a new platform for the development of a new generation of catalysts. [ABSTRACT FROM AUTHOR]

Presents a study which examined how neuronal nitric oxide synthase is expressed in principal cell collecting duct. Information on the use of the reverse transcription-polymerase chain reaction (RT-PCR) technique and immunocytochemical methods in determining the expression of endothelial nitric oxide synthase (eNOS) in the cortical collecting duct (CCD); Information on the methods used in the study; Indications of the results of the study.

One‐pot production of sequence‐controlled block copolymer from mixed monomers is a crucial but rarely reached goal. Using a switchable Lewis‐pair organocatalyst, we have accomplished sequence‐selective polymerization from a mixture of O‐carboxyanhydride (OCA) and epoxide. Polymerization of the OCA monomer occurs first and exclusively because of its exceedingly high polymerizability. When OCA is fully consumed, alternating copolymerization of epoxide and CO2 liberated in OCA polymerization is triggered from the termini of the first block. The two polymerizations thus occur in tandem, both in chemoselective fashion, so that a sequence‐controlled block polymer with up to 99 % CO2 conversion is furnished in this one‐pot protocol. Calculations and experimental results demonstrate a chemoselective and cooperative mechanism, where the high polymerizability of the OCA monomers guarantees exquisite sequence selectivity and the cooperative decarboxylation partly arose from the stabilization effect by triethylborane, which facilitates the smooth transformation of the chain end from carbonate to alkoxide. [ABSTRACT FROM AUTHOR]

One‐pot production of sequence‐controlled block copolymer from mixed monomers is a crucial but rarely reached goal. Using a switchable Lewis‐pair organocatalyst, we have accomplished sequence‐selective polymerization from a mixture of O‐carboxyanhydride (OCA) and epoxide. Polymerization of the OCA monomer occurs first and exclusively because of its exceedingly high polymerizability. When OCA is fully consumed, alternating copolymerization of epoxide and CO2 liberated in OCA polymerization is triggered from the termini of the first block. The two polymerizations thus occur in tandem, both in chemoselective fashion, so that a sequence‐controlled block polymer with up to 99 % CO2 conversion is furnished in this one‐pot protocol. Calculations and experimental results demonstrate a chemoselective and cooperative mechanism, where the high polymerizability of the OCA monomers guarantees exquisite sequence selectivity and the cooperative decarboxylation partly arose from the stabilization effect by triethylborane, which facilitates the smooth transformation of the chain end from carbonate to alkoxide. [ABSTRACT FROM AUTHOR]

Abstract: A facile, mild and rapid solid phase synthetic route free of column chromatographic purification to the synthesis of soluble monodisperse long-chain oligo(1,4-phenyleneethynylene)s is presented. [Copyright &y& Elsevier]

Abstract: A novel in situ deprotection/coupling and iterative divergent/convergent strategy for the synthesis of oligo(1,4-phenyleneethynylene)s is described. [Copyright &y& Elsevier]

To suppress the notorious shuttle effect and capacity fading in lithium-sulfur battery, polyaniline has been introduced due to its multi-anchoring sites for polysulfides, but high content of polyaniline is inevitably accompanied by increase in the inactive content of total cathode and sacrifice in the energy density. Here we disclose that extremely low polyaniline loading can realize excellent cell performance, where conductive polyaniline is uniformly produced on the surface of sulfur-wrapped carbon nanoparticles via dilute aniline polymerization. Even ca. 1 wt% of polyaniline loading is enough to suppress diffusion and dissolution of polysulfides, and the sluggish charge transfer is accelerated. In addition to enhanced cycle stability, a remarkable increase in capacity by ca. 46% is realized compared to sulfur-wrapped carbon composite after 100th at 0.5 C. Moreover, an electrochemical property with coulombic efficiency above 95% and a high capacity retention rate of 55% is achieved even after 500 cycles at ca. 2 wt% polyaniline loading. [ABSTRACT FROM AUTHOR]

Ultra‐low molecular weight (ULMW) CO2‐polyols with well‐defined hydroxyl end groups represent useful soft segments for the preparation of high‐performance polyurethane foams. However, owing to the poor proton tolerance of catalysts towards CO2/epoxide telomerization, it remains challenging to synthesize ULMW yet colorless CO2‐polyols. Herein, we propose an immobilization strategy of constructing supported catalysts by chemical anchoring of aluminum porphyrin on Merrifield resin. The resulting supported catalyst displays both extremely high proton tolerance (≈8000 times the equivalents of metal centers) and independence of cocatalyst, affording CO2‐polyols with ULMW (580 g mol−1) and high polymer selectivity (>99 %). Moreover, the ULMW CO2‐polyols with various architectures (tri‐, quadra‐, and hexa‐arm) can be obtained, suggesting the wide proton universality of supported catalysts. Notably, benefiting from the heterogeneous nature of the supported catalyst, colorless products can be facilely achieved by simple filtration. The present strategy provides a platform for the synthesis of colorless ULMW polyols derived from not only CO2/epoxides, but also lactone, anhydrides etc. or their combinations. [ABSTRACT FROM AUTHOR]

Ultra‐low molecular weight (ULMW) CO2‐polyols with well‐defined hydroxyl end groups represent useful soft segments for the preparation of high‐performance polyurethane foams. However, owing to the poor proton tolerance of catalysts towards CO2/epoxide telomerization, it remains challenging to synthesize ULMW yet colorless CO2‐polyols. Herein, we propose an immobilization strategy of constructing supported catalysts by chemical anchoring of aluminum porphyrin on Merrifield resin. The resulting supported catalyst displays both extremely high proton tolerance (≈8000 times the equivalents of metal centers) and independence of cocatalyst, affording CO2‐polyols with ULMW (580 g mol−1) and high polymer selectivity (>99 %). Moreover, the ULMW CO2‐polyols with various architectures (tri‐, quadra‐, and hexa‐arm) can be obtained, suggesting the wide proton universality of supported catalysts. Notably, benefiting from the heterogeneous nature of the supported catalyst, colorless products can be facilely achieved by simple filtration. The present strategy provides a platform for the synthesis of colorless ULMW polyols derived from not only CO2/epoxides, but also lactone, anhydrides etc. or their combinations. [ABSTRACT FROM AUTHOR]

Exploiting non‐covalent interactions to catalyze challenging ionic polymerizations is an ambitious goal but is in its infancy. We recently demonstrated non‐covalent anion‐binding catalysis as an effective methodology to enable living cationic polymerization (LCP) of vinyl ethers in an environmentally benign manner. Here, we further elucidate the structure‐reactivity relationships of the elaborately designed seleno‐cyclodiphosph(V)azanes catalysts and the roles of anion‐binding interactions by a combined theoretical DFT study and experimental study. The investigation suggests that the distinct cis‐cyclodiphosph(V)azane framework combined with "selenium effect" and electron‐withdrawing 3,5‐(CF3)2‐Phenyl substitution pattern in catalyst enables a critical contribution to accessing excellent stability, anion affinity and solubility under polymerization conditions. Thus, the catalyst could leverage anion‐binding interactions to precisely control reversible and transient dormant‐active species equilibrium, allowing it to dynamically bind, recognize and pre‐organize propagating ionic species and monomer, thereby facilitating efficient chain propagation and minimizing irreversible chain transfer events under mild conditions. The more in‐depth understanding of the mechanism for anion‐binding catalytic LCP reported herein should help to guide future catalyst design and to extend this concept to broader polymerization systems where ionic species serve as crucial intermediates. [ABSTRACT FROM AUTHOR]

Exploiting non‐covalent interactions to catalyze challenging ionic polymerizations is an ambitious goal but is in its infancy. We recently demonstrated non‐covalent anion‐binding catalysis as an effective methodology to enable living cationic polymerization (LCP) of vinyl ethers in an environmentally benign manner. Here, we further elucidate the structure‐reactivity relationships of the elaborately designed seleno‐cyclodiphosph(V)azanes catalysts and the roles of anion‐binding interactions by a combined theoretical DFT study and experimental study. The investigation suggests that the distinct cis‐cyclodiphosph(V)azane framework combined with "selenium effect" and electron‐withdrawing 3,5‐(CF3)2‐Phenyl substitution pattern in catalyst enables a critical contribution to accessing excellent stability, anion affinity and solubility under polymerization conditions. Thus, the catalyst could leverage anion‐binding interactions to precisely control reversible and transient dormant‐active species equilibrium, allowing it to dynamically bind, recognize and pre‐organize propagating ionic species and monomer, thereby facilitating efficient chain propagation and minimizing irreversible chain transfer events under mild conditions. The more in‐depth understanding of the mechanism for anion‐binding catalytic LCP reported herein should help to guide future catalyst design and to extend this concept to broader polymerization systems where ionic species serve as crucial intermediates. [ABSTRACT FROM AUTHOR]

Chemically recyclable polymers that can depolymerize into their constituent monomers are attractive candidates to replace non‐recyclable petroleum‐derived plastics. However, the physical properties and mechanical strengths of depolymerizable polymers are commonly insufficient for practical applications. Here we demonstrate that by proper ligand design and modification, aluminum complexes can catalyse stereoretentive ring‐opening polymerization of dithiolactone, yielding highly isotactic polythioesters with molar masses up to 45.5 kDa. This material can form crystalline stereocomplex with a Tm of 94.5 °C, and exhibits mechanical performances comparable to petroleum‐based low density polyethylene. Exposure of the polythioester to aluminum precatalyst used to synthesized it resulted in depolymerization to pristine chiral dithiolactone. Experimental and computational studies suggest that aluminum complexes have appropriate binding affinity with sulfide propagating species, thereby avoiding catalyst poisoning and minimizing epimerization reactions, which has not been accessible using other metal catalysts. Overall, aluminum catalysis provides access to performance‐advantaged stereoregular recyclable plastics as a promising alternative to petrochemical plastics, thus incentivizing improved plastic sustainability. [ABSTRACT FROM AUTHOR]

Chemically recyclable polymers that can depolymerize into their constituent monomers are attractive candidates to replace non‐recyclable petroleum‐derived plastics. However, the physical properties and mechanical strengths of depolymerizable polymers are commonly insufficient for practical applications. Here we demonstrate that by proper ligand design and modification, aluminum complexes can catalyse stereoretentive ring‐opening polymerization of dithiolactone, yielding highly isotactic polythioesters with molar masses up to 45.5 kDa. This material can form crystalline stereocomplex with a Tm of 94.5 °C, and exhibits mechanical performances comparable to petroleum‐based low density polyethylene. Exposure of the polythioester to aluminum precatalyst used to synthesized it resulted in depolymerization to pristine chiral dithiolactone. Experimental and computational studies suggest that aluminum complexes have appropriate binding affinity with sulfide propagating species, thereby avoiding catalyst poisoning and minimizing epimerization reactions, which has not been accessible using other metal catalysts. Overall, aluminum catalysis provides access to performance‐advantaged stereoregular recyclable plastics as a promising alternative to petrochemical plastics, thus incentivizing improved plastic sustainability. [ABSTRACT FROM AUTHOR]

The AP2/ERF transcription factor family is one of the most important gene families in plants and plays a vital role in plant abiotic stress responses. Although Erianthus fulvus is very important in the genetic improvement of sugarcane, there are few studies concerning AP2/ERF genes in E. fulvus. Here, we identified 145 AP2/ERF genes in the E. fulvus genome. Phylogenetic analysis classified them into five subfamilies. Evolutionary analysis showed that tandem and segmental duplication contributed to the expansion of the EfAP2/ERF family. Protein interaction analysis showed that twenty-eight EfAP2/ERF proteins and five other proteins had potential interaction relationships. Multiple cis-acting elements present in the EfAP2/ERF promoter were related to abiotic stress response, suggesting that EfAP2/ERF may contribute to adaptation to environmental changes. Transcriptomic and RT-qPCR analyses revealed that EfDREB10, EfDREB11, EfDREB39, EfDREB42, EfDREB44, EfERF43, and EfAP2-13 responded to cold stress, EfDREB5 and EfDREB42 responded to drought stress, and EfDREB5, EfDREB11, EfDREB39, EfERF43, and EfAP2-13 responded to ABA treatment. These results will be helpful for better understanding the molecular features and biological role of the E. fulvus AP2/ERF genes and lay a foundation for further research on the function of EfAP2/ERF genes and the regulatory mechanism of the abiotic stress response. [ABSTRACT FROM AUTHOR]

Ring‐opening copolymerizations have emerged as a powerful approach towards the creation of sustainable polymers. Typical H‐bonding catalysts for ring‐opening are subject to a single catalytic site. Here we describe a H‐bond‐donor/Lewis‐acidic‐boron organocatalyst featuring two distinct catalytic sites in one molecule. The ring‐opening copolymerization of epoxides with anhydride mediated by these modular, and tunable catalysts achieves high selectivity (>99 % polyester selectivity) and markedly higher activity compared to either of the di‐thiourea analogues or any combinations of them. Calculations and experimental studies reveal that the superior catalytic performance arises from tug‐of‐war between two differentiated catalytic sites: thiourea pulls off the propagating chain‐end from boron center, simultaneously enhancing the role of monomer activation and also nucleophilicity of the propagation intermediates. [ABSTRACT FROM AUTHOR]

Ring‐opening copolymerizations have emerged as a powerful approach towards the creation of sustainable polymers. Typical H‐bonding catalysts for ring‐opening are subject to a single catalytic site. Here we describe a H‐bond‐donor/Lewis‐acidic‐boron organocatalyst featuring two distinct catalytic sites in one molecule. The ring‐opening copolymerization of epoxides with anhydride mediated by these modular, and tunable catalysts achieves high selectivity (>99 % polyester selectivity) and markedly higher activity compared to either of the di‐thiourea analogues or any combinations of them. Calculations and experimental studies reveal that the superior catalytic performance arises from tug‐of‐war between two differentiated catalytic sites: thiourea pulls off the propagating chain‐end from boron center, simultaneously enhancing the role of monomer activation and also nucleophilicity of the propagation intermediates. [ABSTRACT FROM AUTHOR]

Incorporation of flexible monomer is regarded as a valid way to the chemical modification of the highly brittle poly(cyclohexene carbonate) (PCHC), which derived from the copolymerization of CO2 and cyclohexene oxide (CHO). However, toxic metal catalyst such as cobalt dominates these terpolymerizations which against the green development philosophy. Here, a series of environmentally benign aluminum porphyrin catalysts with different steric and electronic effects for the terpolymerization of CO2, CHO, and terminal epoxides with various flexible pendant alkyl groups to adjust the properties of PCHC is reported. The resulting terpolymers display a random distribution of cyclohexene carbonate along the backbone with a regulated terminal epoxide insertion from 30% to 70%. Moreover, the mechanical properties can be well regulated in a wide range indicating the feasibility of the present approach. The present study provides a green way to chemical modification of rigid PCHC. [ABSTRACT FROM AUTHOR]

The corrosion protection mechanism by polyaniline based coatings on metals is widely suggested to be due to the formation of an improved interfacial passive layer. However, it is argued against this that just an improved passive layer is not sufficient on metals such as iron and zinc for providing significant delay of cathodic delamination. Instead a significant inhibition of oxygen reduction is required, e.g. by an electronically insulating oxide. In this work results are presented providing proof for the formation of a highly electronically insulating and stable zinc oxide layer underneath an emeraldine base composite coating. It is shown how the Scanning Kelvin Probe (SKP) can be used to screen for such highly insulating oxide layers underneath coatings containing conducting polymer. [ABSTRACT FROM AUTHOR]

In this study, karyotype analysis of F2BC1 progenies between sugarcane (Saccharum spp.) and Erianthus fulvus was conducted. The result showed that most chromosomes of YAU04/14, YAU09/02, YAU09/05, YAU09/26 and YAU09/52 are median region (m) chromosomes, while only a small amount of chromosomes are submedian (sm) chromosomes and median point (M) chromosomes. The karyotype formulae of five experimental materials are In - 106 - 98m + 8sm, 2n= 106= 2M + 104m, In = 106= 4M + 96m + 6sm, In = 102= 2M + 92m + 8sm and 2n = 106= 4M + 96m + 6sm, respectively. The karyotypes of all materials belong to symmetrical 2B type, indicating that the chromosomes of progenies are primitive. [ABSTRACT FROM AUTHOR]

Absolute control over polymer stereo‐ and sequence structure is highly challenging in polymer chemistry. Here, an acid‐orthogonal deprotection strategy is proposed for the iterative synthesis of a family of unimolecular polymers starting with enantiopure serines, featuring precise sequence, stereoconfiguration and side‐chain functionalities that cannot be achieved using traditional polymerization techniques. Acid‐orthogonal deprotections proceed independently of one another by the selection of protecting groups that feature the respective acid‐lability. Under p‐toluenesulfonic acid, acidolysis of tert‐butyloxycarbonyl can proceed exclusively, while low‐dosage trifluoroacetic acid and low temperature only trigger the selective and quantitative cleavage of trityl. The pioneering use of this acid‐orthogonal deprotection chemistry increases the compatibility with otherwise sensitive groups and opens up pathways to facilely introduce structural and functional diversity into stereo‐ and sequence‐defined polymers, thus imparting their unique properties beyond natural biopolymers. [ABSTRACT FROM AUTHOR]

Absolute control over polymer stereo‐ and sequence structure is highly challenging in polymer chemistry. Here, an acid‐orthogonal deprotection strategy is proposed for the iterative synthesis of a family of unimolecular polymers starting with enantiopure serines, featuring precise sequence, stereoconfiguration and side‐chain functionalities that cannot be achieved using traditional polymerization techniques. Acid‐orthogonal deprotections proceed independently of one another by the selection of protecting groups that feature the respective acid‐lability. Under p‐toluenesulfonic acid, acidolysis of tert‐butyloxycarbonyl can proceed exclusively, while low‐dosage trifluoroacetic acid and low temperature only trigger the selective and quantitative cleavage of trityl. The pioneering use of this acid‐orthogonal deprotection chemistry increases the compatibility with otherwise sensitive groups and opens up pathways to facilely introduce structural and functional diversity into stereo‐ and sequence‐defined polymers, thus imparting their unique properties beyond natural biopolymers. [ABSTRACT FROM AUTHOR]

Summary: Karyotypes provide key cytogenetic information on the phylogenetic relationships and evolutionary origins in related eukaryotic species. Despite our knowledge of the chromosome numbers of sugarcane and its wild relatives, the chromosome composition and evolution among the species in the Saccharum complex have been elusive owing to the complex polyploidy and the large numbers of chromosomes of these species.Oligonucleotide‐based chromosome painting has become a powerful tool of cytogenetic studies especially for plant species with large numbers of chromosomes. We developed oligo‐based chromosome painting probes for all 10 chromosomes in Saccharum officinarum (2n = 8x = 80). The 10 painting probes generated robust fluorescence in situ hybridization signals in all plant species within the Saccharum complex, including species in the genera Saccharum, Miscanthus, Narenga and Erianthus.We conducted comparative chromosome analysis using the same set of probes among species from four different genera within the Saccharum complex. Excitingly, we discovered several novel cytotypes and chromosome rearrangements in these species.We discovered that fusion from two different chromosomes is a common type of chromosome rearrangement associated with the species in the Saccharum complex. Such fusion events changed the basic chromosome number and resulted in distinct allopolyploids in the Saccharum complex. [ABSTRACT FROM AUTHOR]

Methyl sulfide terminated trans-oligo(p-phenylenevinylene) derivatives(OPVn, nis the numberof phenyl rings) were synthesized, and reversible sol–gel transitionwas observed in a variety of organic solvents. Investigations withUV–vis, fluorescence, and 1H NMR spectroscopy revealedthat aromatic π–π stacking and van der Waals forceswere important in the formation of the gels, with the former beingthe main driving force for sol–gel transition. The π-conjugationlength showed a key influence on self-assembly and gelation property:the gel-to-sol transition temperature (Tgel) increased with π-conjugation length. The gels of OPV4–7can self-assemble into one-dimensional fibers with different sizesand shapes, depending on their π-conjugation length. On thebasis of X-ray diffraction measurements and spectroscopic data, aself-assembly model was proposed. Our observation may be useful fordesigning functional π-gelators based on π–πstacking. [ABSTRACT FROM AUTHOR]

• At low temperature the 5%K 2 O-Cu/CA achieved good COS conversion performance. • The surface hydroxyl group is enriched by K loading. • The escaped H 2 S could be adsorbed to be S2- and SO 4 2- on 5 %K 2 O-Cu/CA. • The adsorbent could be regenerated by N 2 regeneration process. COS in natural gas is difficult to be effectively removed at room temperature. Catalytic hydrolysis is a promising method, however, the discrepancy of catalytic active site as well as deactivation factors are the restricting factors. In this paper, the CuO load and alkali metal modification was successfully prepared on carbon aerogel with more mesoporous structure(5 %K 2 O-Cu/CA). The doping of K could improve the pore structure of the sample and is more conducive to the storage of sulfate, obtaining good anti-poisoning properties. Meanwhile, the K load achieved enriched surface hydroxyl groups, which played an important role in COS conversion, and provided enough electronic electron transfers to accelerate the H 2 O dissociation, producing more hydroxyl groups. Then the adsorbed COS could be efficiently captured by the increasing number of weak basic sites at low temperature. Furthermore, after COS transformation the escaped H 2 S could be subsequently adsorbed on 5 %K 2 O-Cu/CA surface and converted to be S2- and SO 4 2- on CuO surface. Finally, the adsorbent capacity and deactivation were studied, and the N 2 regeneration method owns the higher sulfur capacity of 6.01 mg/g with a COS removal efficiency of 100 % for the first time. [ABSTRACT FROM AUTHOR]

Lead (Pb) is one of the most toxic heavy-metal pollutants. Additionally, lead ions (Pb2+) can accumulate in the human body through the food chain, causing irreversible damage through organ damage and system disorders. In the past few years, the detection of Pb2+ has mainly relied on instrumental methods such as atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). Nonetheless, these techniques are complicated in terms of equipment and procedures, along with being time-intensive and expensive in terms of detection. These drawbacks have limited their wide application. Hence, there is a pressing need to develop detection techniques for Pb2+ that are not only cost-efficient but also highly sensitive and specific. A novel "on-off-on" electrochemiluminescence (ECL) sensor for detecting Pb2+ was developed based on the resonance energy transfer (RET) effect between AuNPs and boron nitride quantum dots (BN QDs) and the recognition of Pb2+ by DNAzyme along with the cleavage reaction of the substrate chain. Poly(6-carboxyindole)/stannic sulfide (P6ICA/SnS 2) nanocomposite was employed as a co-reaction accelerator to consequently facilitate the production of intermediate SO 4 •−. This effective enhancement of the reaction led to an improved ECL intensity of BN QDs and enabled the sensor platform to exhibit a higher original ECL response. Benefiting from the combination of the DNAzyme signal amplification strategy with the "on-off-on" design, the ECL sensor showed satisfactory selectivity, good stability, and high sensitivity. This ECL sensor exhibited a linear detection range (LDR) of 10−12-10−5 M and a limit of detection (LOD) of 2.6 × 10−13 M. In the present work, an "on-off-on" ECL sensor is constructed based on RET effect for ultrasensitive detection of Pb2+. P6ICA/SnS 2 was investigated as the co-reaction accelerator in this sensor. Moreover, this ECL sensor exhibited excellent analytical capability for detecting Pb2+ in actual water samples, providing a method for detecting other heavy metal ions as well. [Display omitted] • A "on-off-on" ECL sensor is constructed based on resonance energy transfer (RET) effect for ultrasensitive detection of Pb2+. • P6ICA/SnS 2 as a co-reaction accelerator of this sensor is synthesized. • DNAzyme signal amplification strategy sensing mode greatly improved the sensitivity and accuracy of the sensor. • This sensor shows good sensitivity, stability and selectivity for real samples. [ABSTRACT FROM AUTHOR]

The direct ring‐opening polymerization (ROP) of propylene carbonate (PC) only affords oligomers with substantial unidentified by‐products, which hinders the efficient utilization of PC. Through detailed studies, for the first time, a careful mechanism involving the in situ release of propylene oxide (PO) from PC decarboxylation is proposed. Further, we report a novel strategy of copolymerization of PC/cyclic anhydrides via in situ capture of the formed intermediates. Results show that PC is successfully transformed into polyesters. Especially for the ring‐opening alternating copolymerization (ROAC) of PC/phthalic anhydride (PA), a variety of advantages are manifold: i) slow‐release of PO ensuring a perfectly alternating structure; ii) quantitative and fast transformation of PC; iii) visualization of polymerization process by a CO2 pressure gauge. Of importance, through tandem polymerizations, PC is fully transformed into polyesters and polycarbonates concurrently, thus achieving PC utilization with a high atom‐economy. [ABSTRACT FROM AUTHOR]

The direct ring‐opening polymerization (ROP) of propylene carbonate (PC) only affords oligomers with substantial unidentified by‐products, which hinders the efficient utilization of PC. Through detailed studies, for the first time, a careful mechanism involving the in situ release of propylene oxide (PO) from PC decarboxylation is proposed. Further, we report a novel strategy of copolymerization of PC/cyclic anhydrides via in situ capture of the formed intermediates. Results show that PC is successfully transformed into polyesters. Especially for the ring‐opening alternating copolymerization (ROAC) of PC/phthalic anhydride (PA), a variety of advantages are manifold: i) slow‐release of PO ensuring a perfectly alternating structure; ii) quantitative and fast transformation of PC; iii) visualization of polymerization process by a CO2 pressure gauge. Of importance, through tandem polymerizations, PC is fully transformed into polyesters and polycarbonates concurrently, thus achieving PC utilization with a high atom‐economy. [ABSTRACT FROM AUTHOR]

Erianthus fulvus (TaxID: 154759) is a valuable germplasm resource in sugarcane breeding and research and has excellent agronomic traits, such as drought resistance, cold resistance, barren tolerance and high brix. With a stable chromosome number (2 n  = 20) and a small genome (0.9 Gb), it is an ideal candidate for research on sugarcane. Next-generation sequencing technology has enabled a growing number of studies to focus on genomics. Due to the large amount of omics data available, a centralized platform is necessary for ensuring the consistency, independence and maintainability of these large-scale datasets through storage, analysis and integration. Here, we present a comprehensive database for the E. fulvus genome, EfGD. By using the new high-quality reference genome and its annotations, the EfGD provides the largest whole-genome sequencing reference dataset for E. fulvus , which archives 27 165 protein-coding genes and 55 564 488 SNPs from 202 newly resequenced genomes. Furthermore, we created a user-friendly graphical interface for visualizing genomic diversity, population structure and evolution and provided other tools on an open platform. Database URL : https://efgenome.ynau.edu.cn [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Thermoresponsive polymers with simultaneous biodegradability and signal "self‐reporting" outputs that meet for advanced applications are hard to obtain. To address this issue, we developed fluorescence signal "self‐reporting" biodegradable thermoresponsive polycarbonates through the immortal copolymerization of CO2 and oligoethylene glycol monomethyl ether‐functionalized epoxides in the presence of hydroxyl‐modified tetraphenylethylene (TPE‐OH). TPE‐OH was used as chain transfer agent to afford well‐defined polycarbonates with controlled molecular weight (6000—17000 g·mol–1) and aggregation‐induced emission characteristics. Through temperature‐dependent fluorescence intensity study, low critical solution transition of TPE‐labeled polycarbonates were determined and the fine details of thermal‐induced phase transition process were monitored. Further research indicated that temperature‐controlled aggregation and dissociation of TPE moieties are the main reason for fluorescence intensity variations. We anticipate that this work could offer a method to visualize the thermal transition process of thermoresponsive polycarbonates and broaden their application fields as smart materials. [ABSTRACT FROM AUTHOR]

A novel bifunctional cobalt ‐ porphyrin catalyst which contains a Lewis acidic metal cENter and a quaternary ammonium salt unit in a molecule has beEN developed. This new catalyst system exhibits superior copolymerization activity in comparison to a traditional binary system. [ABSTRACT FROM AUTHOR]

Abstract: The growth rate of oxide film formed at the polyaniline/mild steel interface was investigated by open circuit potential (OCP) measurements. The OCP of polyaniline base (EB) coated electrode displayed three feature changes during immersion: t 1 − t 2, t 2 − t 3 and >t 3, and the oxide film grew mainly in t 2 − t 3 time range. The oxide film growth followed a direct logarithm law, the growth rate decreased with increasing NaCl concentration and temperature. With increasing pH, the growth rate decreased first and then increased. The apparent activation energy of oxide film growth was calculated as −39.8kJ/mol, indicates that oxide film growth was under diffusion control. [Copyright &y& Elsevier]

Abstract: The corrosion protection of emeraldine base (EB) on mild steel in the artificial defect exposed to 1wt% NaCl solution was studied using in situ optical microscope and scanning electron microscopy (SEM). The EB coating displayed good corrosion protection on the exposed bare steel, which was difficult to understand by traditional anodic protection mechanism or inhibitory protection mechanism, or cathodic protection mechanism, since steel usually cannot be passivated in brine, and EB coating cannot release inhibitory anions to protect exposed bare steel, and further, the galvanic coupling measurement demonstrates that EB cannot provide cathodic protection to exposed bare steel. The importance of dissolved oxygen diffusion caused by EB in corrosion protection was disclosed in this paper, a related protection model was therefore proposed, which was qualitatively verified by corresponding electrochemical measurements. [Copyright &y& Elsevier]

Abstract: Poly(propylene carbonate) (PPC), a biodegradable plastic produced by alternating copolymerization of carbon dioxide and propylene oxide, is amorphous at glass-transition temperature of ∼35 °C; therefore, it becomes brittle at temperatures <20 °C. This article reports on the synthesis of low molecular weight urethanes, such as 1,6-bis(hydroxyethyl urethane)hexane (BEU), 1,6-bis(hydroxyisopropyl urethane)hexane (BPU), and 1,6-bis(methyl urethane)hexane (HDU) bearing rich NH and Cby a non-isocyannate method and their use as plasticizers for PPC. The hydrogen-bonding interaction between BPU and PPC was found to be significantly more effective as compared with BEU and HDU, and the highest hydrogen-bonding interaction fraction reached 5.2% in a PPC/BPU blend with 15 wt% BPU loading. Solubility parameters calculated from Hoy’s method, in combination with differential scanning calorimetric analysis, indicated that HDU and BPU were miscible with PPC at a molecular scale, while BEU was immiscible with PPC. Usually, plasticizing is generally accompanied by sacrificing of tensile strength; however, it was encouraging to observe that the elongation at break for PPC/HDU blend with 10 wt% of HDU loading reached 727% – an increase 53 times that of pure PPC – while the tensile strength was maintained at 30 MPa, which was comparable with that of linear low-density polyethylene. The hydrogen-bonding interaction generated a remarkable improvement in the mechanical performance of PPC; it not only confined the migration of the plasticizer to the surface and thus ensured stability of the blending material over time, but it also maintained the mechanical strength of the plasticized PPC. [Copyright &y& Elsevier]

Recently, rare earth ternary coordination catalyst represented as Y(CCl3OO)3-Glycerin-ZnEt2 has been used for producing poly(propylene carbonate) (PPC, an alternating copolymer of carbon dioxide and propylene oxide) in industry scale, but its catalytic activity needs further improvement. One reason for the relatively low catalytic activity lied in that only 11.7% of active center was efficient due to possible embedding of active center in the heterogeneous catalyst. In this report, supporting strategy was developed, where Y(CCl3OO)3-Glycerin-ZnEt2 was supported on various inorganic oxides. Two supporting methods were carried out. One way was to mix Y(CCl3OO)3-Glycerin with inorganic oxide first and then ZnEt2 was dropped to form the supported catalyst, and the other was to make Y(CCl3OO)3-Glycerin-ZnEt2 at first and then mixing with inorganic oxides. The former showed decreasing catalytic activity compared with corresponding unsupported rare earth ternary catalyst, while an improvement of 16-36% in catalytic activity was realized in the latter. PPC with an average number molecular weight ( Mn) of over 100 kg/mol and carbonate unit (CU) content of higher than 96% was prepared by both supported catalysts. The catalytic activity of the supported catalyst depended significantly on the supports, which increased in the following order: α-Al2O3 < MgO < ZnO ≈ SiO2 <γ-Al2O3. γ-Al2O3 was the best support for rare earth ternary catalyst, which showed a remarkable 36% increase in catalytic activity, corresponding to the utilization of 17% of active center. Although MgO supported catalyst gave only an 8% increase in catalytic activity, the Mn and CU content of PPC were raised to about 143 kg/mol and 99%, whereas the PPC from common rare earth ternary catalyst was about 108 kg/mol and 97%, respectively. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

Poly(cyclohexene carbonate) (PCHC) is an alternative copolymer of carbon dioxide and cyclohexene oxide. Severe thermal decomposition occurs during melt processing of PCHC, thus, it is important to find the reason for thermal decomposition and raise its thermal stability. In this report, as-polymerized PCHC was obtained under Y(CClCOO)-ZnEt-glycerin rare earth coordination ternary catalyst. The pyrolysis gas chromatography with mass spectrometry analysis disclosed that chain unzipping depolymerization dominated the thermal decomposition process. The residue metal (mainly ZnO in this catalyst system) was important in PCHC degradation, and the onset decomposition temperature of PCHC containing 5 ppm zinc was 56 °C higher than that of PCHC containing 4,400 ppm Zn, corresponding to apparent activation energy change from 190 KJ/mol to 146 KJ/mol. When PCHC was subjected to melt processing, its average molecular weight decreased more rapidly, as it contained more catalyst residue, indicating metal residue in PCHC could accelerate the decomposition process, and removing the metal residue should be effective in raising its thermal stability. [ABSTRACT FROM AUTHOR]