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Structural variations (SVs) are a feature of plant genomes that has been largely unexplored despite their significant impact on plant phenotypic traits and local adaptation to abiotic and biotic stress. In this study, we employed woolly grape (Vitis retordii), a species native to the tropical and subtropical regions of East Asia with both coastal and inland habitats, as a valuable model for examining the impact of SVs on local adaptation. We assembled a haplotype‐resolved chromosomal reference genome for woolly grape, and conducted population genetic analyses based on whole‐genome sequencing (WGS) data from coastal and inland populations. The demographic analyses revealed recent bottlenecks in all populations and asymmetric gene flow from the inland to the coastal population. In total, 1,035 genes associated with plant adaptive regulation for salt stress, radiation, and environmental adaptation were detected underlying local selection by SVs and SNPs in the coastal population, of which 37.29% and 65.26% were detected by SVs and SNPs, respectively. Candidate genes such as FSD2, RGA1, and AAP8 associated with salt tolerance were found to be highly differentiated and selected during the process of local adaptation to coastal habitats in SV regions. Our study highlights the importance of SVs in local adaptation; candidate genes related to salt stress and climatic adaptation to tropical and subtropical environments are important genomic resources for future breeding programs of grapevine and its rootstocks. [ABSTRACT FROM AUTHOR]

Artificial vesicles are recognized as powerful platforms for a large body of research across the disciplines of chemistry, physics and biology. Despite the great progress, control of the size distribution to make uniform vesicles remains fundamentally difficult due to the highly uncontrollable growth kinetics, especially for micron‐sized vesicles. Here we report a template‐free living self‐assembly method to prepare monodisperse vesicles around 1 μm from an alternating copolymer. The polymer forms nanodisks (ca. 9 nm) in N,N‐dimethylformamide (DMF), acting as seeds for subsequent growth. By adding water, the nanodisks gradually grow into larger circular bilayer nanosheets, which bend to crowns and continue to grow into uniform micron‐sized vesicles. The first‐order growth kinetics as well as the small size polydispersity index (<0.1) suggests the living self‐assembly characteristics. This work paves a new way in both living self‐assembly and monodisperse polymer vesicles. [ABSTRACT FROM AUTHOR]

Epigenetic modifications play critical roles during somatic cell nuclear transfer (SCNT) embryo development. Whether RNA N6‐methyladenosine (m6A) affects the developmental competency of SCNT embryos remains unclear. Here, we showed that porcine bone marrow mesenchymal stem cells (pBMSCs) presented higher RNA m6A levels than those of porcine embryonic fibroblasts (pEFs). SCNT embryos derived from pBMSCs had higher RNA m6A levels, cleavage, and blastocyst rates than those from pEFs. Compared with pEFs, the promoter region of METTL14 presented a hypomethylation status in pBMSCs. Mechanistically, DNA methylation regulated METTL14 expression by affecting the accessibility of transcription factor SP1 binding, highlighting the role of the DNA methylation/SP1/METTL14 pathway in donor cells. Inhibiting the DNA methylation level in donor cells increased the RNA m6A level and improved the development efficiency of SCNT embryos. Overexpression of METTL14 significantly increased the RNA m6A level in donor cells and the development efficiency of SCNT embryos, whereas knockdown of METTL14 suggested the opposite result. Moreover, we revealed that RNA m6A‐regulated TOP2B mRNA stability, translation level, and DNA damage during SCNT embryo development. Collectively, our results highlight the crosstalk between RNA m6A and DNA methylation, and the crucial role of RNA m6A during nuclear reprogramming in SCNT embryo development. [ABSTRACT FROM AUTHOR]

The selective semihydrogenation of C2H2 to C2H4 in crude C2H4 (with ~1 vol % C2H2 contamination) is a crucial process in the manufacture of polyethylene. Comparing to conventional thermalcatalytic route with Pd as catalyst under high temperature with H2 as hydrogen source, photocatalytic C2H2 reduction reaction with H2O as hydrogen source can achieve high selectivity under milder conditions, but has rarely been reported. Here, we present a kind of ultrathin metal–organic framework nanosheets (Cu‐Co‐MNSs) that demonstrate excellent catalytic activities in the semihydrogenation of C2H2. Employing Ru(bpy)32+ as the photosensitizer, this catalyst attains a noteworthy turnover number (TON) of 2124 for C2H4, coupled with an impressive selectivity of 99.5 % after 12 h visible light irradiation. This performance is comparable to molecular catalysts and notably surpasses the efficiency of bulk metal–organic framework materials. Furthermore, Cu‐Co‐MNSs achieve a 99.95 % conversion of C2H2 under industrial relevant conditions (1.10 % C2H2 in C2H4) with 90.3 % selectivity for C2H4 over C2H6, demonstrating a great potential for polymer‐grade C2H4 production. [ABSTRACT FROM AUTHOR]

Hierarchical self‐assembly of synthetic polymers in solution represents one of the sophisticated strategies to replicate the natural superstructures which lay the basis for their superb functions. However, it is still quite challenging to increase the degree of complexity of the as‐prepared assemblies, especially in a large scale. Liquid–liquid phase separation (LLPS) widely exists in cells and is assumed to be responsible for the formation of many cellular organelles without membranes. Herein, through integrating LLPS with the polymerization‐induced self‐assembly (PISA), a coacervate‐assisted PISA (CAPISA) methodology to realize the one‐pot and scalable preparation of hierarchical bishell capsules (BCs) from nanosheets with ultrathin lamellae phase (sub‐5 nm), microflakes, unishell capsules to final BCs in a bottom‐up sequence is presented. Both the self‐assembled structure and the dynamic formation process of BCs have been disclosed. Since CAPISA has combined the advantages of coacervates, click chemistry, interfacial reaction and PISA, it is believed that it will become a promising option to fabricate biomimetic polymer materials with higher structural complexity and more sophisticated functions. [ABSTRACT FROM AUTHOR]

This article explores the origin and evolution of the Y chromosome in kiwifruit. The sex determination of kiwifruit is genetically controlled by an XY system, and two Y-linked sex-determining genes, Shy Girl (SyGl) and Friendly Boy (FrBy), have been identified. The study examines the structural reorganization of the kiwifruit Y chromosome and identifies the sex-determining region (SDR) on chromosome 25 in A. chinensis and chromosome 12 in A. eriantha. The research also investigates the genomic diversity and evolutionary trajectories of the Y chromosome in kiwifruit. [Extracted from the article]

Construction of polymer‐based artificial solid‐electrolyte interphase films on Zn metal anode holds great potential in the suppression of both dendrite growth and side reaction in rechargeable aqueous Zn‐ion batteries. However, the traditional polymer films suffer from the critical issues of sluggish Zn2+ transport kinetics and rigid interface. Herein, zinc alginate (ZA) hydrogel is designed and prepared as a dynamic interface and Zn2+ redistributor on Zn anode via in situ cross‐linking reaction. The zincophilic and negatively charged carboxyl groups of ZA promote the transport of Zn2+ ions along a "Z‐type" pathway, the repulsion of free SO42‐ anions, and the desolvation of Zn2+ ions, consequently leading to the homogeneous deposition of Zn and the effective suppression of side reaction. Additionally, the dynamic flexibility of ZA hydrogel endows the Zn anode with self‐adapting interface to accommodate the volume variation and repair the possible ruptures, thereby guaranteeing the long‐term cycling stability. Assisted by the ZA layer, the Zn anode achieves a prolonged lifespan over 2200 h without the formation of Zn dendrites and by‐products. Outstanding cycling stability is also demonstrated for the Zn anode when coupled with MnO2 cathode, further demonstrating its prospects for practical application. [ABSTRACT FROM AUTHOR]

Inspired by carbon monoxide dehydrogenase (CODH), mimicking its inner and outer spheres is a promising strategy in CO2 reduction catalyst design. However, artificial CODH‐like catalysts are generally limited to the inner sphere effect and only applicable in organic solvents or for electrocatalysis. Herein, an aqueous CODH mimic with both inner and outer spheres for photocatalysis is reported. In this polymeric unimolecular catalyst, the inner sphere is composed of cobalt porphyrin with four appended amido groups and the outer sphere consists of four poly(2‐(dimethylamino)ethyl methacrylate) (PDMAEMA) arms. Upon visible light irradiation (λ >420 nm), the as‐prepared catalyst exhibits a turnover number (TONCO) of 1731.2 in the reduction of CO2 into CO, which is comparable to most reported molecular catalysts in aqueous solution. The mechanism studies indicate that, in this water‐dispersible and structurally well‐defined CODH mimic, the cobalt porphyrin core serves as the catalysis center and the amido groups function as hydrogen‐bonding pillars helping to stabilize the CO2 adduct intermediate, whereas the PDMAEMA shell renders both water solubility and a CO2 reservoir through reversibly capturing of CO2. The present work has clarified the significance of coordination sphere effects for improving the aqueous photocatalytic CO2 reduction performance of CODH mimics. [ABSTRACT FROM AUTHOR]

Supramolecular self‐assembly is a promising strategy for stabilizing the photo‐sensitive components in photocatalysis. However, the underlying correlation between the enhanced photostability and supramolecular structure at the molecular level has not yet been fully understood. Herein, we develop a biomimetic vesicular membrane‐based polyporphyrin photocatalyst exhibiting excellent photocatalytic stability with at least activity time of 240 h in hydrogen generation. Time‐domain ab initio modelling together with transient absorption spectroscopy, visual frontier orbitals and Gibbs free energy calculation disclose that the ordered aggregation of porphyrin units in the vesicle membrane facilitates "hot" electron relaxation and the rapid dissipation of photo‐generated charges, thereby contributing to the longevity. This work deepens the molecular‐level understanding on photostability and photocatalytic mechanism of supramolecular photocatalysts. [ABSTRACT FROM AUTHOR]

Lithium/thionyl chloride (Li/SOCl2) primary batteries are appealing power solutions because of their remarkable electrochemical performances. However, their mass applications are hindered by the challenges in sustainability, cost and safety concerns owing to the employed Li chemistry. Here, magnesium (Mg) chemistry is shown as a promising alternative through synergistic optimization of electrolyte solvation and electrode reaction kinetics. The first Mg/SOCl2 primary battery yields surprisingly high specific capacities up to ≈14 000 mAh g−1 at a decent discharge voltage of ≈1.67 V, which outperforms the state‐of‐the‐art Mg‐based primary batteries. In addition, it retains almost 100% of the original capacity after 20‐day reservation. The impressive battery performances are originated from the stabilized MgCl2 formation on high‐surface‐area carbon cathode and suppressed Mg anode corrosion via the Mg‐induced solvation effect. Mg/SOCl2 primary batteries are promising candidates for low‐cost and recyclable power supplies, and they thus open new avenues for the development of sustainable battery chemistries. [ABSTRACT FROM AUTHOR]

Quality consistency of Glycyrrhiza formula granules is essential for guaranteeing clinical efficacy. However, a suitable method to accurately and conveniently evaluate the consistency of the clinical efficacy of Glycyrrhiza formula granules is currently not available. This study established a method for the simultaneous determination of 12 active components in Glycyrrhiza formula granules using ultra‐high‐performance liquid chromatography coupled with quadrupole‐time‐of‐flight tandem mass spectrometry. The rate of inhibition of cyclooxygenase‐2 by different batches of Glycyrrhiza formula granules was determined. Near‐infrared spectra were collected for different batches of Glycyrrhiza formula granules to detect their biological activity in the inhibition of cyclooxygenase‐2. The quality consistency of the 11 batches of Glycyrrhiza formula granules was evaluated using principal component and correlation analyses. The results showed significant differences in the formula granules of Glycyrrhiza uralensis produced by the different manufacturers. Some differences were also observed among batches of formula granules produced by the same manufacturer. Correlation analysis of the chemical components and cyclooxygenase‐2 activity showed that glycyrrhizic acid, liquiritin, and isoliquiritin were the main active components of Glycyrrhiza. Correlation analysis of the near‐infrared spectra and cyclooxygenase‐2 inhibition activity showed a high correlation between the active components and three characteristic bands: 3383–3995, 4227–4651, and 5315–5878 cm−1. In this study, the main active anti‐inflammatory components of Glycyrrhiza granules were screened. Thus, the near‐infrared spectrum and characteristic active band of multi‐index active components can be used to quickly detect the quality consistency of Glycyrrhiza formula granules, thereby improving the ability to control the quality and consistency of these granules. [ABSTRACT FROM AUTHOR]

This study presents interesting self‐assembly of peapod‐like micrometer tubes from a planet‐satellite‐type supramolecular megamer, which was constructed through the specific host–guest molecular recognition between azobenzene (AZO)‐functionalized hyperbranched poly(ethyl‐3‐oxetanemethanol)‐star‐poly(ethylene oxide) (HSP‐AZO) and β‐cyclodextrin(CD)‐based hydrophilic hyperbranched polyglycerol (CD‐g‐HPG). A peapod‐like structure with micrometer‐sized tube as the pod and vesicles encapsulated inside as the peas was formed through sequential vesicle entosis, linear association, and fusion processes. Dissipative particle dynamics (DPD) simulations support the structural possibility of the supramolecular peapod formation and its mechanism. UV light irradiation could lead to the disassembly of the peapod‐like structure. This study expands the family of supramolecular polymers and opens a new avenue to develop bioinspired complex hierarchical nanoarchitectures at the microscopic level. [ABSTRACT FROM AUTHOR]

Leukocytes of the mother sow were also shown a few GFP positive cells, and the second column showed that most of these GFP positive cells were CD3+ cells. We found that 0.043% of GFP positive cells were present in PBMC and 88.3% of these cells were CD3 SP + sp T cells (Figure 1G). To find out whether foetal cells could also circulate through the blood to other organs of the surrogates, we euthanized the sows after delivery and examined the presence of GFP positive cells in other organs by freezing sections (Method S5). The presence of a tiny population of foreign cells or DNA in an organism is known as microchimerism. [Extracted from the article]

As a kind of promising drug carriers, smart polymers have attracted much attention due to the effective and controlled drug release in target cells. Herein, a reactive oxygen species (ROS)‐responsive thioether‐containing amphiphilic hyperbranched polymer prepared from MTPA and TMPTGE (HBPMT) is synthesized from 3‐(methylthio)propylamine (MTPA) and trimethylolpropane triglycidyl ether (TMPTGE) by the amine‐epoxy click reaction via A2 + B3 one‐pot approach. Benefiting from its inherent amphiphilic nature, HBPMT can self‐assemble into stable micelles in water. Triggered by H2O2, these micelles can be dissociated rapidly because hydrophobic thioether segments in their cores are oxidized into hydrophilic sulfoxide or sulfone groups. Additionally, the ROS produced by photosensitizer under light irradiation can also play the same role of H2O2. Such HBPMT micelles can be utilized to encapsulate anticancer drug paclitaxel (PTX) and photosensitizer chlorin e6 (Ce6) simultaneously for drug delivery and control release. The methyl thiazolyl tetrazolium assay toward MCF‐7 tumor cells (a human breast adenocarcinoma cell line) indicates that these micelles encapsulated with PTX and Ce6 exhibit a significant combinational efficacy of cell proliferation inhibition, which means the promising potential for synergistic chemo‐photodynamic cancer therapy. Such a novel nanocarrier based on amphiphilic to hydrophilic transition would provide a candidate for controlled drug release and cancer combination therapy. [ABSTRACT FROM AUTHOR]

The cytoskeleton is one of the most important cellular components. Up to now, most of the reported artificial cytoskeletons are based on a gel‐in‐vesicle strategy. Herein, we report a membrane‐bound inward‐growth pathway to prepare cytoskeleton‐like and radially aligned nanofibers grown from capsule membranes to get membrane‐bound artificial cytoskeletons (MACs). The mechanism therein is disclosed through the direct observation of the intermediates in both dried and liquid states. Furthermore, the as‐prepared MACs show a selective disassembly behavior in the presence of reductants: both capsule membranes and MACs can be disassembled or only MACs can be disassembled through the selective introduction of dynamic disulfide bonds (DS) into them and by the switch of ultraviolet (UV) irradiation. The present work provides a new hierarchical self‐assembly way to construct artificial cytoskeletons with controlled compositions and orientations. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous Zn‐ion batteries (ZIBs) are regarded as one of the most promising devices for the next‐generation energy storage system. However, the uncontrolled dendrite growth on Zn metal anodes and the side hydrogen evolution reaction, which has not yet been well considered, hinder the practical application of these batteries. Herein, a uniform and robust metallic Sb protective layer is designed based on the theoretic calculation and decorated on Zn plate via in situ replacement reaction. Compared with the bare Zn plate, the as‐prepared Zn@Sb electrode provides abundant zincophilic sites for Zn nucleation, and homogenizes the electric field around the Zn anode surface, both of which promote the uniform Zn deposition to achieve a dendrite‐free morphology. Moreover, the Gibbs free energy (∆GH) calculation and in situ characterization demonstrate that hydrogen evolution reaction can be effectively suppressed by the Sb layer. Consequently, Sb‐modified Zn anodes exhibit an ultralow voltage hysteresis of 34 mV and achieve excellent cycling stability over 1000 h with hydrogen‐ and dendrite‐free behaviors. This work provides a facile and effective strategy to suppress both hydrogen evolution reaction and dendrite growth. [ABSTRACT FROM AUTHOR]

Resveratrol is a polyphenol with antiaging and anticancer effects. Most previous studies used a single analysis to determine the key functions of resveratrol in inhibiting cancer progression. However, most of the signal transmission pathways in biological processes are multilevel. We used bioinformatics to elucidate the mechanism of resveratrol inhibition of breast cancer development. The mRNA expression profile of GSE25412 from the National Center for Biotechnology Information (NCBI) and the microRNA (miRNA) expression profile of PubMed identifier (PMID) 26890143 were integrated. De novo motifs were used to obtain predicted transcription factor (TF) motifs for differentially expressed genes. The regulatory effect of resveratrol on key nodes in the comprehensive analysis results was verified. The TF–miRNA–mRNA interaction network based on the STITCH and miRDB databases showed that resveratrol exerted a dual inhibitory effect by activating inhibitory TFs to block the cell cycle and inhibit miRNAs from upregulating apoptosis. However, these two processes did not work completely independently. TP53 is the dominant hub gene associated with the cell cycle and apoptosis throughout the TF–miRNA network. Kaplan–Meier plotter analysis found that resveratrol‐induced expression changes in key RNAs, such as E2F2, JUN, FOS, BRCA1, CDK1, CDKN1A, TNF, and hsa‐miR‐34a‐5p, significantly improved the prognosis of breast cancer patients, which was further verified using real‐time quantitative PCR (qPCR) and western blotting. This study constructed a TF–miRNA regulatory network with TP53 and E2F as the main central genes to elucidate the molecular mechanism of resveratrol in the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Hybrid organic–inorganic perovskite single crystals, compared with their polycrystalline counterparts in thin films, are free from grain boundaries and have fewer defects, and therefore are promising in high‐performance optoelectronic devices. Recently, the crystal‐structure anisotropy in perovskites has been utilized to achieve polarization‐sensitive photodetectors. Here, it is shown that under 532 nm linearly polarized illumination, although MAPbBr3 (MA=CH3NH3+1) single crystals possess weak in‐plane anisotropy, nanogratings made on the crystal surface lead to high polarization photodetection sensitivity of ≈2.2 comparable with that of the isotropic perovskite crystals and nanowires, while enhancing both the photodetection responsivity and external quantum efficiency. The surface nanopattern induced polarization sensitivity may find interesting applications in future optoelectronic devices. [ABSTRACT FROM AUTHOR]

Engineering synthetic materials that mimic the complex rhythmic oscillatory behavior of living cells is a fundamental challenge in science and technology. Up to now, the reported synthetic model system still cannot compete with nature in oscillatory modes and amplitudes. Presented here is a novel alternating copolymer vesicle that exhibits drastic and multimode shape oscillations in real time, which are controlled by polymer concentrations and driven by the Belousov—Zhabotinsky oscillatory reaction, including swelling/deswelling, twisting/detwisting, stretching/shrinking, fusion/fission, and multiple division. Some of them, especially the fission oscillation, have not been observed before. In addition, the oscillation magnitude with regard to diameter is much larger than that of previously reported self‐oscillating vesicles. Such a self‐oscillating vesicle transformer would extend the complexity and capacity of membrane deformations in synthetic systems, approaching those of natural cells. [ABSTRACT FROM AUTHOR]

Marine mussels have the ability to cling to various surfaces at wet or underwater conditions, which inspires the research of catechol‐functionalized polymers (CFPs) to develop high‐performance adhesive materials. However, these polymeric adhesives generally face the problems of complex synthetic route, and it is still high challenging to prepare CFPs with excellent adhesive performance both at dry and underwater conditions. Herein, a mussel‐inspired alternating copolymer, poly(dopamine‐alt‐2,2‐bis(4‐glycidyloxyphenyl)propane) (P(DA‐a‐BGOP)), is synthesized in one step by using commercially available monomers through epoxy‐amino click chemistry. The incorporation of polar groups and rigid bisphenol A structures into the polymer backbone enhances the cohesion energy of polymer matrix. The alternating polymer structure endows the polymers with high catechol content and controlled polymer sequence. As a result, P(DA‐a‐BGOP) exhibits a strong bonding strength as high as 16.39 ± 2.13 MPa on stainless steel substrates after a hot pressing procedure and displays a bonding strength of 1.05 ± 0.05 MPa on glass substrates at an under‐seawater condition, which surpasses most commercial adhesives. [ABSTRACT FROM AUTHOR]

The topmost polyamide (PA) layer of the thin‐film‐composite reverse osmosis (RO) membrane is the most important part in the membrane‐based RO technology. With the aid of molecular dynamics simulations, many PA layer‐related features in the RO process can be revealed. With many novel types of PA RO membranes out of trimesoyl chloride/m‐phenylenediamine monomers developed in the laboratory, a convenient model building tool for these PA layer systems is urgently needed to conduct the theoretical analysis. Here, we develop a new universal toolkit for constructing PA RO membranes, named as MembrFactory, which combines flexibility of force fields and membrane compositions. A key characteristic of our approach is the use of monomers as the starting state, and the final membrane model was obtained automatically by stepwise reaction between the functional groups on the monomers. The reliability of MembrFactory has been validated by constructing several common PA RO membranes. © 2019 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A surfactant‐stabilized coordination strategy is used to make two‐dimensional (2D) single‐atom catalysts (SACs) with an ultrahigh Pt loading of 12.0 wt %, by assembly of pre‐formed single Pt atom coordinated porphyrin precursors into free‐standing metal–organic framework (MOF) nanosheets with an ultrathin thickness of 2.4±0.9 nm. This is the first example of 2D MOF‐based SACs. Remarkably, the 2D SACs exhibit a record‐high photocatalytic H2 evolution rate of 11 320 μmol g−1 h−1 via water splitting under visible light irradiation (λ>420 nm) compared with those of reported MOF‐based photocatalysts. Moreover, the MOF nanosheets can be readily drop‐casted onto solid substrates, forming thin films while still retaining their photocatalytic activity, which is highly desirable for practical solar H2 production. [ABSTRACT FROM AUTHOR]

Polymer self‐assembly has been a hot research topic for several decades. Different types of polymers with various architectures, like block copolymers, brush polymers, hyperbranched polymers and dendrimers, etc. are currently being investigated. Alternating copolymers (ACPs) are regular copolymers with an alternating monomeric unit structure in the polymer backbones. However, despite the great progress in the synthesis of ACPs, their self‐assembly is still in an infant stage. Very recently, our group reported a new type of amphiphilic ACPs through click copolymerization and obtained spheres, vesicles, nanotubes, and even hierarchical sea urchin‐like aggregates through the self‐assembly process. In addition, we have found some intriguing features in the self‐assembly of amphiphilic ACPs when compared with other copolymers, including their facile syntheses, readily functionalization, novel self‐assembly structures, new folding‐chain mechanisms, and uniform but ultrathin feature length. In this Concept article, we present the self‐assembly of amphiphilic ACPs together with their unique features by reviewing our latest results and related studies. Moreover, the future perspective on the self‐assembly of amphiphilic ACPs is also proposed. Our aim is to capture the attention and interest of chemists in this new area of polymerization. Click polymerization: Self‐assembly of amphiphilic alternating copolymers into diverse structures by solvent switching or emulsion‐assisted polymerization‐induced self‐assembly methods is summarized (see figure). The unique characteristics of these structures are determined both experimentally and theoretically. [ABSTRACT FROM AUTHOR]

Abstract: Hierarchical solution self‐assembly has become an important biomimetic method to prepare highly complex and multifunctional supramolecular structures. However, despite great progress, it is still highly challenging to prepare hierarchical self‐assemblies on a large scale because the self‐assembly processes are generally performed at high dilution. Now, an emulsion‐assisted polymerization‐induced self‐assembly (EAPISA) method with the advantages of in situ self‐assembly, scalable preparation, and facile functionalization was used to prepare hierarchical multiscale sea urchin‐like aggregates (SUAs). The obtained SUAs from amphiphilic alternating copolymers have a micrometer‐sized rattan ball‐like capsule (RBC) acting as the hollow core body and radiating nanotubes tens of micrometers in length as the hollow spines. They can capture model proteins effectively at an ultra‐low concentration (ca. 10 n m) after functionalization with amino groups through click copolymerization. [ABSTRACT FROM AUTHOR]

This communication describes polymer vesicles self-assembled from hyperbranched polymers (branched polymersomes (BPs)) as scaffolds, conceptually mimicking the natural light-harvesting system in aqueous solution. The system is constructed with hydrophobic 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) as donors encapsulated in the hydrophobic hyperbranched cores of the vesicles and the hydrophilic Rhodamine B (RB) as acceptors incorporated on the surface of the vesicles through the cyclodextrin (CD)/RB host-guest interactions, through which the donors and acceptors are spatially separated to effectively avoid the self-quenching between donors. This vesicular light harvesting system has presented good energy transfer efficiency of about 80% in water, and can be used as the ink to write multiclolor letters. In addition, due to the giant dimension of BPs, the real-time fluorescent images of the vesicles under an optical microscope can be observed to prove the light-harvesting process. It is supposed that such a vesicular light-harvesting antenna can be used to construct artificial photosynthesis systems in the future. [ABSTRACT FROM AUTHOR]

In this paper, a kind of novel water-soluble chitosan-polydopamine ( CHT-PDA) nanoparticles with a hydrodynamic diameter ( Dh) around 10 nm were reported by the combination of self-polymerization of PDA and electrostatic complexation between PDA and CHT in water/ DMSO (W/D) mixture at the molar fraction of DMSO ( xDMSO = 0.37). The preparation method was efficient with a yield of 98% around. The as-prepared water-soluble CHT-PDA nanoparticles exhibited effective UV-screen ability, enhanced visible-light transmittance and good cytocompatibility via MTT assay, which might be used in transparent formulation for UV protection usage, especially in biological field including sun care application. [ABSTRACT FROM AUTHOR]

A facile and novel method for the synthesis of monodisperse hyper-crosslinking polymer nanoparticles (HPNs) is reported in the combination of vesicle bilayer templating and hyper-crosslinking technology. Monodisperse polymer nanoparticles (PNs) around 61 nm are first obtained through the confined reaction of vinylbenzyl chloride and divinylbenzene in the bilayers of the vesicles, and then the PNs are turned into HPNs through the Friedel-Crafts-type hyper-crosslinking reaction. The finally obtained HPNs demonstrate small and uniform size, high Brunauere-Emmette-Teller surface area up to ≈1300 m2 g−1, a very high micropore area above 1000 m2 g−1 and a micropore volume of 0.55 cm3 g−1. In addition, they also show the carbon dioxide adsorption capacity of 2.87 mmol g−1 (273 K, 1 bar), which is among the best CO2 adsorption property for 'Davankov Resins.' [ABSTRACT FROM AUTHOR]

A dandelion-like supramolecular polymer (DSP) with a 'sphere-star-parachute' topological structure consisting of a spherical hyperbranched core and many parachute-like arms is constructed by the non-covalent host-guest coupling between a cyclodextrin-endcapped hyperbranched multi-arm copolymer (host) and many functionalized adamantanes with each having three alkyl chain arms (guests). The obtained DSPs can further self-assemble into nanotubes in water in a hierarchical way from vesicles to nanotubes through sequential vesicle aggregation and fusion steps. The nanotubes have a bilayer structure consisting of multiple 'hydrophobic-hyperbranched-hydrophilic' layers. Such a structure is very useful for constructing a chlorosome-like artificial aqueous light-harvesting system, as demonstrated here, via the incorporation of hydrophobic 4-(2-hydroxyethylamino)-7-nitro-2,1,3-benzoxadiazole as donors inside the hyperbranched cores of the nanotubes and the hydrophilic Rhodamine B as the acceptors immobilized on the nanotube surfaces. This as-prepared nanotube light harvesting system demonstrates unexpectedly high energy transfer efficiency (above 90%) in water. This extends supramolecular polymers with more complex topological structure, special self-assembly behavior, and new functionality. [ABSTRACT FROM AUTHOR]

Amicelle-like hybrid natural-artificial light-harvesting nanosystem was prepared through protein-framed electrostatic self-assembly of phycocyanin and a four-armed porphyrin star polymer. The nanosystem has a special structure of pomegranate-like unimolecular micelle aggregate with one phycocyanin acceptor in the center and multiple porphyrin donors in the shell. It can inhibit donor self-quenching effectively and display efficient transfer of excitation energy (about 80.1%) in water. Furthermore, the number of donors contributing to a single acceptor could reach as high as about 179 in this nanosystem. [ABSTRACT FROM AUTHOR]

Well-defined ultrathin nanotubes (30 nm in diameter and of micrometer-scale length) were generated through the self-assembly of a novel alternative copolymer synthesized using an epoxy-thiol click-chemistry reaction. The self-assembly mechanism was investigated both by experiments and using dissipative particle dynamics (DPD) simulations. The obtained nanotubes can be readily functionalized with carboxy groups, amino groups, peptides, or other groups by simple modular click copolymerization. [ABSTRACT FROM AUTHOR]

Hyperbranched multiarm copolymers (HMCs) have been shown to hold great potential as precursors in self-assembly, and many impressive supramolecular structures have been prepared through the self-assembly of HMCs in solution. However, theoretical studies on the corresponding self-assembly mechanism have been greatly lagging behind. Herein, we report the self-assembly of normal or reverse vesicles from amphiphilic HMCs by dissipative particle dynamics (DPD) simulation. The simulation disclosed both the self-assembly mechanisms and dynamics of vesicles. It indicates that the self-assembly of HMCs involves several steps, from randomly distributed unimolecular micelles to small spherical micelles, to membrane-like micelles, to finally small vesicles. The membranes are formed through the direct aggregation and lateral fusion of small micelles, and the bending and closing of the membranes give rise to small vesicles. Finally, large and steady vesicles are formed through the fusion of small vesicles. In addition, the bilayer or monolayer molecular packing modes as well as the mircrophase separation behaviors of HMCs in normal or reverse vesicles have also been studied. These simulation results explore details that cannot be observed in the experiments to a certain degree, and have extended the understanding of the vesicular self-assembly process of HMCs. [ABSTRACT FROM AUTHOR]

Climate is one of the most important drivers for adaptive evolution in forest trees. Climatic selection contributes greatly to local adaptation and intraspecific differentiation, but this kind of selection could also have promoted interspecific divergence through ecological speciation. To test this hypothesis, we examined intra- and interspecific genetic variation at 25 climate-related candidate genes and 12 reference loci in two closely related pine species, Pinus massoniana Lamb. and Pinus hwangshanensis Hisa, using population genetic and landscape genetic approaches. These two species occur in Southeast China but have contrasting ecological preferences in terms of several environmental variables, notably altitude, although hybrids form where their distributions overlap. One or more robust tests detected signals of recent and/or ancient selection at two-thirds (17) of the 25 candidate genes, at varying evolutionary timescales, but only three of the 12 reference loci. The signals of recent selection were species specific, but signals of ancient selection were mostly shared by the two species likely because of the shared evolutionary history. FST outlier analysis identified six SNPs in five climate-related candidate genes under divergent selection between the two species. In addition, a total of 24 candidate SNPs representing nine candidate genes showed significant correlation with altitudinal divergence in the two species based on the covariance matrix of population history derived from reference SNPs. Genetic differentiation between these two species was higher at the candidate genes than at the reference loci. Moreover, analysis using the isolation-with-migration model indicated that gene flow between the species has been more restricted for climate-related candidate genes than the reference loci, in both directions. Taken together, our results suggest that species-specific and divergent climatic selection at the candidate genes might have counteracted interspecific gene flow and played a key role in the ecological divergence of these two closely related pine species. [ABSTRACT FROM AUTHOR]

Vesicle-vesicle aggregation to mimic cell-cell aggregation has attracted much attention. Here, hyperbranched polymer vesicles (branched-polymersomes, BPs) with a cell-like size were selected as model membranes, and the vesicle aggregation process, triggered by click chemistry of the copper-catalysed azide-alkyne cycloaddition reaction, was systematically studied. For this purpose, azide and alkynyl groups were loaded on the membranes of BPs through the co-assembly method to obtain N3-BPs and Alk-BPs, respectively. Subsequently, macroscopic vesicle aggregates were obtained when these two kinds of functional BPs were mixed together with the ratio of azide to alkynyl groups of about 1:1. Both the vesicle fusion events and lateral phase separation on the vesicle membrane occurred during such a vesicle aggregation process, and the fusion rate and phase-separation degree could be controlled by adjusting the clickable group content. The vesicle aggregation process with N3-micelles as desmosome mimics to connect with Alk-BPs through click-chemistry reaction was also studied, and large-scale vesicle aggregates without vesicle fusion were obtained in this process. The present work has extended the controllable cytomimetic vesicle aggregation process with the use of covalent bonds, instead of noncovalent bonds, as the driving force. [ABSTRACT FROM AUTHOR]

Hyperbranched polymers (HBPs), invented at the end of 1980s, are one important subclass of the fourth generation macromolecular architectures following the linear, branched, and crosslinking polymers. Due to their unique topological structure and interesting physical/chemical properties, HBPs have attracted wide attention from both academia and industry. HBPs are composed of linear units, dendritic units, and terminal units. The degree of branching (DB), a term to describe the composition of these three structure units and thus the branching architecture of polymers, is one of the most important intrinsic parameters for HBPs. This review has summarized the effect of the DB on the physical and chemical properties of HBPs, including the rheological property, crystallization and melting behaviors, glass transition, thermal and hydrolytic degradations, phase characteristics, lower critical solution temperature phase transition, optoelectronic properties, encapsulation capability, self-assembly behavior, biomedical applications, and so on. Such a structure and property relationship will build a bridge between the syntheses and applications of HBPs, especially in the application areas of functional materials, biomedical materials, and nanotechnology. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1277-1286, 2011 [ABSTRACT FROM AUTHOR]