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Amphiphilic molecules can self-assemble in solution into a variety of supramolecular assemblies, ranging from simple micelles, ribbons, and tubes to complex cubosomes with bicontinuous cubic nanostructures. It is well known that the self-assembly of chiral building blocks into one-dimensional (1D) twisted fibers, helical ribbons, and tubes enables chiral transfer from the molecular scale to super-assemblies. In this study, we investigate the chirality of three-dimensional (3D) supramolecular assemblies, such as colloidal onions, cubosomes, and hexosomes, formed from the same chiral heteroclusters. Unlike supramolecular 1D helical ribbons, these assemblies do not have chiral external shapes or chiral internal nanostructures, but they do exhibit circular dichroism, suggesting that they are chiral. Structural studies revealed that the ordered arrangement of the chiral units in curved superstructures is the origin of the supramolecular chirality of these 3D assemblies. Therefore, this study provides insights for enriching the diversity and complexity of supramolecular chiral assemblies.

Multiwalled carbon nanotubes (MWCNTs) are currently widely used and are expected to be used as drug carriers and contrast agents in clinical practice. Previous studies mainly focused on their lung toxicity; therefore, their effects on the vascular endothelium are unclear. In this study, a human angiogenesis array was used to determine the effect of MWCNTs on the expression profile of angiogenic factors in endothelial cells and to clarify the role of vascular endothelial growth factor (VEGF) in MWCNT-induced endothelial cell injury at the cellular and animal levels. The results indicated that MWCNTs (20-30 nm and 30-50 nm) could enter endothelial cells and disrupt human umbilical vein endothelial cell (HUVECs) activity in a concentration-dependent manner. MWCNTs disrupted the tube formation ability and cell migration function of HUVECs. The results from a Matrigel Plug experiment in mice showed that angiogenesis in the MWCNT experimental group was significantly reduced. The results of a protein chip analysis indicated that VEGF expression in the MWCNT treatment group was decreased, a finding that was validated by ELISA results. The protein expression levels of AKT and eNOS in the MWCNT treatment group were significantly decreased; the administration of recombinant VEGF significantly alleviated the migration ability and tube formation ability of endothelial cells injured by MWCNTs, upregulated the protein expression of AKT and eNOS, and increased the number of neovascularization in mice in the MWCNT treatment group. This study demonstrated that MWCNTs affect angiogenesis via the VEGF-Akt-eNOS axis which can be rescued by VEGF endothelial treatment.

Heteroclusters constructed by tethering dissimilar nanoclusters using organic linkers resemble lipids and self-assemble into cubosomes, namely, microparticles of soft crystals composed of unique nanochannel lattices with a defined symmetry and topology. The internal porous crystal structures can be accurately characterized using transmission electron microscopy. We herein describe twin boundaries and five-fold twin boundaries in cubosomes with a double-diamond Pn3m structure. Our analysis indicates a clear distinction in the conformation of the skeletal unit: a centrosymmetric staggered conformation with point group D3d for the normal skeletal unit and a mirror-symmetric eclipsed one with point group D3h for the skeletal unit on the twin boundary. This symmetry distinction causes the channels to change direction and elongate slightly as they pass through the twin boundary, but the topology is maintained. For cubosomes containing five-fold twin boundaries, one of the channels is in the center of the particles seamlessly connecting the five blocks. Our conclusion is that the two distinct channel systems are still continuous. This fundamental understanding will contribute to the development of soft crystals with defined shapes and special inner nanostructures for advanced applications.

Organic polymers have been found widespread commercial applications due to their easy processing and attractive mechanical properties. Concurrently, inorganic polyoxometalates (POMs), a class of metal-oxygen anionic and nanosized clusters of early transition metals, have a wide range of attractive functions and are used in industrial catalysis. In this communication, we report a new approach to creating the first linear poly(polyoxometalate)s that combine the advantages of polymers and POM clusters. In the experiment, a POM-containing norbornene monomer was first synthesized by linking a Wells-Dawson-type POM with a norbornene derivative. The monomer was polymerized in the presence of a Grubbs catalyst under mild conditions with yields nearly 100% in a living and controllable manner. The resulting poly(polyoxometalate)s have controllable molecular weights and a well-defined hybrid structure of an organic polynorbornene backbone with large pendant groups of the nanosized POM clusters. Thus, they form good films and have a good catalytic performance. Our findings not only pave the way for incorporating the POM clusters into polymers with well-defined structures and high molecular weights, but also offer a competitive strategy for developing more novel catalytic systems by introducing the poly(polyoxometalate)s.

Diverse nanostructures and nano-objects for advanced applications are created by the self-assembly of lipids, surfactants, and block copolymers. Understanding this process is critical for improving their functions and expanding their applications. Accordingly, we pioneered the synthesis and application of heterocluster Janus molecules (HCJMs), which resemble conventional amphiphiles. Their self-assembly into nanostructures and nano-objects can be directly characterized by transmission electron microscopy (TEM), allowing the process to be unraveled through the monitoring of the intermediates. In this study, we focused on the TEM characterization of HCJM-based colloidal onions, which have an onion-like inner structure, to gain insight into the self-assembly process from molecules to perfect onions. Multiple mechanisms, including molecular aggregation, structural ordering within aggregates into colloidal onions, and layer-by-layer growth caused by particle coarsening, contributed to the overall self-assembly process. The analysis also indicated that the reduction in the Gibbs free energy and bending free energy of curved layers are the driving forces for structural ordering and onion growth. Finally, this work provided a useful method for preparing colloidal onions for attractive applications in nanomedicine and other areas.

This study aimed to investigate the role of apoptotic bodies (Abs) from the oxidative stressed endplate chondrocytes in regulating mineralization and potential mechanisms. Endplate chondrocytes were isolated from rats and treated with H2O2 to induce oxidative stress. The calcium deposition for matrix mineralization in the cells was examined by histological staining. The expression levels of calcification‐related genes in individual groups of cells were determined by quantitative real time‐PCR (qRT‐PCR). Subsequently, extracellular vesicles (EVs) were purified and characterized. The effect of treatment with H2O2 and/or Abs on the mineralization, extracellular PPi metabolism and related gene expression were determined. Oxidative stress significantly increased the mineralization and promoted the generation of main Abs from endplate chondrocytes. Abs were effectively endocytosed by endplate chondrocytes and co‐localized with collagen (COL)‐II in the cytoplasm, which enhanced the mineralization, alkaline phosphatase (ALP), osteocalcin (OCN), Runt‐related transcription factor 2 (RUNX2) and COL‐I expression in endplate chondrocytes. Furthermore, treatment either H2O2 or Abs significantly decreased PPi, but increased Pi production and treatment with both further enhancing the changes in endplate chondrocytes. Similarly, treatment either H2O2 or Abs significantly decreased the ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), and ankylosis protein (ANK) expression and ENPP1 promoter activity, but increased the tissue‐nonspecific alkaline phosphatase (TNAP) expression and TNAP promoter activity in endplate chondrocytes. Oxidative stress promoted the generation of Abs, which might enhance the oxidative stress‐mediated mineralization in endplate chondrocytes by regulating the PPi metabolism.

The polyacidic character of polyoxometalate (POM) clusters endows high ionic conductivity, making these clusters good candidates for solar and fuel cells. Covalent bonding of clusters to polymer chains creates poly(POM)s that are polyelectrolytes with both cluster functions and polymer performance. Thus, solution-processable poly(POM)s are expected to be used as key materials in advanced devices. Further understanding of poly(POM)s will optimize the preparation process and improve device performance. Herein, we report a study of the first linear poly(POM)s by directly visualizing the chains using scanning transmission electron microscopy. Compared with traditional polymers, individual clusters of poly(POM)s can be directly visualized because of the resistance to electron-beam damage and the high contrast of the tungsten POM pendants. Thus, cluster aggregates with diverse shapes were observed. Counting the number of clusters in the aggregates allowed the degree of polymerization and molecular weight distribution to be determined, and studying the aggregate shapes revealed the presence of a curved semirigid chain in solution. Further study of shape diversity revealed that strong interactions between clusters determine the diverse chain shapes formed during solution processing. Fundamental insight is critical to understanding the formation of poly(POM) films from solutions as key functional materials, especially for fuel and solar cells.

Clusters are an important class of nanoscale molecules or superatoms that exhibit an amazing diversity in structure, chemical composition, shape, and functionality. Assembling two types of clusters is creating emerging cluster-assembled materials (CAMs). In this paper, we report an effective approach to produce quasi two-dimensional (2D) CAMs of two types of spherelike clusters, polyhedral oligomeric silsesquioxanes (POSS), and polyoxometalates (POM). To avoid macrophase separation between the two clusters, they are covalently linked to form a POM-POSS cocluster with Janus characteristics and a dumbbell shape. This Janus characteristics enables the cocluster to self-assemble into diverse nanoaggregates, as conventional amphiphilic molecules and macromolecules do, in selective solvents. In our study, we obtained micelles, vesicles, nanosheets, and nanoribbons by tuning the n-hexane content in mixed solvents of acetone and n-hexane. Ordered packing of clusters in the nanosheets and nanoribbons were directly visualized using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) technique. We infer that the increase of packing order results in the vesicle-to-sheet transition and the change in packing mode causes the sheet-to-ribbon transitions. Our findings have verified the effectivity of creating quasi 2D cluster-assembled materials though the cocluster self-assembly as a new approach to produce novel CAMs.

Organic polymers and inorganic clusters belong to two different disciplines and have completely different properties and structures. When a cluster is attached to the backbone of a polymer as a pendant, the resultant hybrid polymers (polyclusters) exhibit unique behaviours totally different from those of conventional polymers owing to the nanoscale size of the cluster and its particular interactions. Herein, the aggregation of a poly(polyoxometalate)-a polynorbornene backbone with inorganic polyoxometalate cluster pendants-upon addition of a non-solvent to its dilute solution is reported. A three-dimensional network of tangled and snake-like nanothreads was observed. Direct visualisation of individual nanoscale clusters enabled identification of single chains within the nanothreads. These observations suggest that during the process of aggregation, the hybrid polymer forms curved or extended chains as a consequence of an armouring effect in which the collapsed cluster pendants wrap around the backbone. The collapse occurs because they become less soluble in the solvent/non-solvent mixture. The extended chains then become entwined and form nanoropes consisting of multiple chains wound around each other. This study provides a deeper understanding of the nature of polyclusters and should also prove useful for their future development and application.

Cubosomes are bicontinuous cubic-phase particles generated by amphiphile self-assembly with bicontinuous cubic phases, which creates an intricate network of interconnected nanochannels that endow these materials with special functions for advanced applications. On the other hand, clusters are an attractive class of molecules that exhibit intriguing functions and properties that differ from those of atoms and nanoparticles. Inspired by lipid self-assembly and attracted to the new functionalities of clusters, we prepared special heterocluster Janus dumbbells (HCJDs) composed of dissimilar nanoclusters: namely, a polyoxometalate and a polyhedral oligomeric silsesquioxane. HCJDs resemble conventional amphiphiles and, as such, they self-assemble in solution into faceted hybrid cubosomes via the transformation of vesicles into spongelike aggregates. Multiple mechanisms that lead to equilibrium, including molecular self-assembly, vesicle accumulation, membrane fusion, inner-structure reorganization, and cubic crystal growth, contributed to the overall process. On the basis of these results, we proposed a strategy for self-assembly-from basic molecular design that goes beyond traditional amphiphiles to the construction of micro- or nanomaterials with hierarchical structures and advanced functions.

Cluster materials have attracted much attention because of their unique chemical and physical properties, hitherto unseen in bulk materials. Inspired by the lipid self-assembly principle, a series of heterocluster Janus molecules (HCJMs) with atomic precision have been rationally designed and synthesized by connecting different clusters via covalent bonds for the construction of nanomaterials and nano-objects. Due to their amphiphilicity, HCJMs self-assemble into cluster-containing nanomaterials or nano-objects with versatile ordered structures beyond those observed in conventional crystals. Their hybrid composition and nanoscale size are also greatly advantageous in the study of their fine structure by electron microscopy techniques, and enable their formation mechanisms to be unraveled. Finally, the influence of the characteristics of the HCJMs on the structure and properties of the self-assembled nano-objects are explored comprehensively. This synthesis strategy will promote further development of cluster materials with advanced functions via rational molecular design toward the construction of hierarchical nanostructures via molecular self-assembly.

Background Gouty arthritis (GA) is a chronic disease caused by monosodium urate crystal deposition. Repeated attacks of arthritis may lead to the deposition of urate to form gout stone, resulting in joint deformity and joint damage. Although GA is not fatal, it causes low work productivity and low quality of life. Western drug, such as febuxostat, colchicine, allopurinol, often cannot get satisfying curative effect, and may even lead to serious side effects, such as exfoliative dermatitis or uremia. However, the therapeutic effect of Traditional Chinese medicine is very satisfactory. The treatment effect of simiao powder, a Chinese patent medicine, combined with acupuncture was widely used on treatment of GA. Although it has been widely used in clinical practice, its relative effectiveness and safety have not been confirmed. Therefore, this study will use meta-analysis to verify the efficacy and safety of simiao powder combined with acupuncture in the treatment of GA. Methods All randomized controlled trial of simiao powder combined with acupuncture for the treatment of RA from their inception 29 October, 2020 will be searched form the China National Knowledge Infrastructure, Wanfang Database, Chinese Science and Technology Periodical Database, Chinese Biomedical Literature Database, Pubmed, Embase, Web of Science, and the Cochrane library. Two authors will independently select studies, extract data based on pre-designed inclusion and exclusion criteria. Methodological quality assessment and risk of bias will be assessed using Cochrane bias risk tool. All data analysis will be conducted using Revman5.3, WinBUGS 1.4.3, and Stata14.2 software. Results We will compare the different outcome indicators of various studies to provide a synthesis of the efficacy and safety of Simiao powder combined with acupuncture for GA patients. The main outcome measures included efficacy, remission rate (no drug symptoms), recurrence rate, clinical absolute score and relative score. Secondary outcome measures included related adverse reactions and uric acid concentration. Conclusion The findings of the study will provide helpful evidence for the efficacy and safety of simiao powder combined with acupuncture in the treatment of GA. Registration number This study protocol have been funded through a protocol registry. The registry number is INPLASY2020110028.

We reported that the self-assembly of the polyoxometalate–organic conjugate can be well controlled and regulated by means of a temperature-mediated approach. The conjugate comprised of an organically modified Anderson-type polyoxometalate cluster with two cholesterol moieties, considering that the symmetrical and rigid structure of the Anderson-type polyoxometalate cluster is an excellent building block for constructing functional supramolecular assemblies, and cholesterol is widely explored to fabricate desired self-assemblies, due to its planar structure together with the van der Waals interactions between molecules. Utilizing the temperature-mediated approach, the conjugate assembled into micrometre scale crystalline rods at 40.0 °C, and an organogel at 20.0 °C, in mixed DMF/toluene solvents (v/v = 1 : 9). For crystalline rods, they were constituted with a lot of ultralong and rigid microrods, and for organogel, it was immobilized by massive short and elongated nanoribbons. Moreover, a mechanism has been proposed to explain the self-assembly behavior of the conjugate at different temperatures. This temperature-mediated approach may provide a feasible method for the fabrication of nanostructural materials for various applications.

Soft nanotubes are normally constructed from chiral amphiphiles through helical self-assembly. Yet, how to self-assemble achiral molecules into nanotubes is still a challenge. Here, we report the nanotube construction with achiral shape amphiphiles through helical self-assembly and also unravel the formation mechanisms. The amphiphiles have a dumbbell shape and are composed by covalently linking three achiral moieties together: two unlike clusters and an organic tether. The difference in polarity between the unlike clusters drives the amphiphiles to self-assemble into single- and multi-walled nanotubes as well as intermediates. Analysis of the key intermediates unravels the self-assembly mechanism of helicity-selective nucleation and growth. Meanwhile, direct visualization of the individual clusters in the ribbons displays a two-dimensional deformed hexagonal lattice. Thus, we speculate that it is the lattice deformation that creates anisotropic tension along different directions of the ribbon which further results in the formation of helical ribbons towards nanotubes by amphiphiles.

Honeycomb structure endows graphene with extraordinary properties. But could a honeycomb monolayer superlattice also be generated via self-assembly of colloids or nanoparticles? Here we report the construction of mono- and multilayer molecular films with honeycomb structure that can be regarded as self-assembled artificial graphene (SAAG). We construct fan-shaped molecular building blocks by covalently connecting two kinds of clusters, one polyoxometalate and four polyhedral oligomeric silsesquioxanes. The precise shape control enables these complex molecules to self-assemble into a monolayer 2D honeycomb superlattice that mirrors that of graphene but on the mesoscale. The self-assembly of the SAAG was also reproduced via coarse-grained molecular simulations of a fan-shaped building block. It revealed a hierarchical process and the key role of intermediate states in determining the honeycomb structure. Experimental images also show a diversity of bi- and trilayer stacking modes. The successful creation of SAAG and its stacks opens up prospects for the preparation of novel self-assembled nanomaterials with unique properties.

The unique performance of natural materials stems from their hierarchical hybrid structures formed through self-assembly. The self-assembly principles of natural materials have been exploited to create artificial materials. Herein, we demonstrate a bottom-up approach that produces polymer nanocomposites as well as a self-assembled nanoenhancer for tailoring the polymer properties. The polymer is a poly(ethylene glycol) (PEG), and the nanoenhancer is aggregates formed by self-assembly of a hybrid. The hybrid is prepared through covalent bonding of a surfactant-encapsulated polyoxometalate (S-POM) complex with a PEG chain and can form aggregates composed of an S-POM complex bilayer sandwiched by two PEG layers. The lateral size of aggregates changes, depending on the conditions used in the sample preparation. Hence, we examined four nanostructures in the solid samples of nanocomposites: hybrid self-assembled nanosheets, PEG crystallized lamellae, PEG/hybrid cocrystallized lamellae, and hybrid crystallized l...

A hybrid block copolymer (H-BCP) composed of a poly(polyoxometalate) (poly(POM)) block and a poly(6-norbornene-hexanoic acid) (poly(COOH)) block was prepared by sequential addition of two norbornene monomers containing a POM cluster and a carboxyl as side groups via ring-opening metathesis polymerization (ROMP). Because the 5833 Da molecular weight of the POM-containing monomer is much higher than 277 Da of the carboxyl-containing monomer, the designed H-BCP has a degree of polymerization DP = 5 for the poly(POM) block and DP = 200 for the poly(COOH) block. Thus, the H-BCP not only has differences in its chemical structure and properties but also asymmetries in its molecular weight and length. In acetonitrile, it self-assembles into hybrid micelles with a thin shell of the poly(POM) block and a core of the poly(COOH) block. The micelles form thin films in which the micelles pack into a hexagonal pattern driven by attractive capillary forces between the micelles. Meanwhile, the H-BCP exhibits good catalytic activity. The H-BCP may become an important candidate for producing hybrid materials with good processability and ductility of the polymer components, and good functionality of the POM clusters.

A bottom-up strategy for the preparation of hierarchical hybrid materials with good thermostability is reported. The hybrid molecule was constructed from a Wells–Dawson-type polyoxometalate (POM) cluster and a poly(ethylene glycol) (PEG) chain through covalent-bond formation. The large distinction between the POM cluster and PEG chain results in a microphase separation to form POM and PEG layers that further alternatively arrange into hybrid lamellae with a sub-20 nm thickness. Then the hybrid lamellae could simultaneously organize into spherulitic superstructures. Because of this hierarchical structuring, strong electrostatic interactions between POM clusters are maximized within the POM layers. This gives rise to thermostability. Structurally, the hybrid lamellae and the superstructures are unchanged, even at 160 °C, and indeed the shear storage modulus of the hybrid material remains nearly constant within this same temperature range. This study demonstrates the concept of bottom-up hybridization, in which rationally selecting building blocks, designing the hybrid molecule, and then manipulating hierarchical structures can generate thermostable hybrid materials.

We report our study on the enhanced thermal stability of organogels through forming self-reinforcing supramolecular assemblies of a polyoxometalate (POM)-containing hybrid gelator. The designed and synthesized gelator has a molecular structure of cholesterol–POM–cholesterol. In our experiment, we found an intriguing phenomenon: the hybrid gelator could dissolve in toluene at 80 °C and the solutions became immobilized when cooled to room temperature, that is, organogels formed. However, the toluene organogels could not be converted into the solutions when they were reheated to 80 °C or an even higher temperature like 120 °C, which is ca. 10 °C higher than the boiling point (110.8 °C) of toluene. This result reveals that the organogels of the hybrid gelator have a high thermal stability. We demonstrated that the rationally designed hybrid gelator assembled in its toluene organogel into a single-molecule-layer nanoribbon, within which an orderly POM layer was sandwiched between the two cholesterol layers. This ordered structure could maximize the interactions of the POM clusters, so the POM layer was found to profoundly reinforce the nanoribbons and the cholesterol layers were considered to produce the nanoribbons with good compatibility with toluene. In this way, the thermal stability of this hybrid organogel in toluene was greatly enhanced.

The aim of this study was to explore the influence of fluoride exposure and ERα gene polymorphisms on reproductive hormone concentrations of women in accordance with endemic fluorosis residence.A cross sectional study was conducted in Tongxu county, Henan Province, China. A total of 679 women were recruited using cluster sampling and each subject provided fasting blood and an associated urine sample. We measured the concentrations of serum gonadotropin releasing hormone (GnRH), follicle-stimulating hormone, luteinizing hormone, and estradiol and urinary fluoride.In the defluoridation project group (DFPG), serum GnRH was lower in women carrying C/C genotype compared to in those carrying C/T and T/T genotypes of ERα gene rs3798577 (p0.05). In the endemic fluorosis group (EFG), serum GnRH was lower in women carrying Pp genotype compared to in those carrying PP and pp genotypes of ERα PvuII (p0.05). Serum GnRH in women from EFG who carried Pp, pp, Xx and xx genotypes in ERα gene PvuII and XbaI was lower than in those in the control group (CG) who carried same genotypes (p0.05). Furthermore, serum GnRH in women from EFG was significantly lower than in those in CG, regardless of whether the women were carrying C/C, C/T or T/T genotypes of ERα rs3798577 (p0.05). Serum estradiol concentrations in EFG were significantly lower than in CG when the women were carrying the Pp, Xx and T/T genotypes in ERα gene (p0.05).Interaction of ERα gene and fluoride exposure may influence women's serum reproductive hormone concentrations.背景与目的：探讨氟暴露及ERα 基因多态性对氟病区女性生殖激素浓度的影 响。方法与研究设计：按照饮用水中氟浓度分为氟病区组、改水组和对照组。 采用整群抽样的方法选择中国通许县居住的679 名成年女性为研究对象，采集 研究对象空腹静脉血及晨尿样本， 并测量血清促性腺激素释放激素 （gonadotropin releasing hormone, GnRH）、卵泡刺激素、促黄体生成素、雌二 醇和尿氟浓度。结果：改水组携带ERα rs3798577 C/C 基因型女性血清GnRH 浓 度低于携带C/T 和T/T 基因型女性（p0.05）。氟病区组携带ERα PvuII Pp 基 因型女性血清GnRH 浓度低于携带PP 和pp 基因型女性（p0.05）。携带ERα PvuII Pp、pp 和ERα XbaI Xx、xx 基因型的女性血清GnRH 浓度低于对照区携 带相同基因型的女性（p0.05）。此外，无论其携带的ERα rs3798577 基因型是 C/C 、C/T 或T/T ， 氟病区组女性血清GnRH 浓素均低于对照区女性 （p0.05）。携带ERα PvuII Pp, ERα XbaI Xx 和ERα rs3798577 T/T 基因型的氟 病区女性血清雌二醇浓度低于携带相同基因型的对照区女性（p0.05）。结 论：ERα 基因和氟暴露的交互作用可能影响女性血清生殖激素的浓度。.

We report the construction of dumbbell-shaped hybrid molecules for programming their hierarchical supramolecular nanostructures through a synergetic self-assembly. Our first dumbbell-shaped hybrid molecule is a POM-organic-POSS cocluster produced by covalently coupling a POM cluster and a POSS cluster together through an organic tether. Structural analyses demonstrated a highly ordered lamellar morphology with a 4.9 nm periodicity, indicating a strong thermodynamic force driving a nanoscale phase separation of the POM and POSS blocks. The POM clusters were arranged in an orderly fashion within the POM-containing layer with a 1.38 nm periodicity because of fixed shape and size of the cluster. This investigation provides in-depth understanding of how to construct hierarchical supramolecular nanostructures at a nanoscale less than 5 nm by manipulating and controlling the topological shape of hybrid molecules.

Functionalization and post-functionalization of polyoxometalates (POMs) by organic groups or biological moieties can provide versatile platforms for creating novel functional hybrids with synergetic properties. Such materials can easily be envisioned as having many advanced applications in biology and materials science. Nowadays, the organic groups or biological moieties used for conjugation with POMs, can readily become increasingly complicated in terms of structure, size and properties. Accordingly, a major challenge lies in the development of efficient conjugation methods. In this work, we report our application of metal-free Diels–Alder click reactions under mild conditions to covalently link an Anderson-type polyoxomolybdate with some organic groups or biological moieties possessing complex structures or different properties. High coupling efficiencies and facile purification methods guarantee > 90 % yields. Clearly, this is an ideal methodology for the synthesis of the post-functionalized POM hybrids. With this technology now in hand, finding valuable applications for such post-functionalized POM hybrids will be a highly significant focus of future investigations.

In this work, we report the preparation of complex nano-objects by means of a stepwise self-assembly of two polymer-polyoxometalate hybrids (PPHs) in solution. The PPHs are designed and synthesized by tethering two linear poly(ε-caprolactone)s (PCL) of different molecular weights (MW) on a complex of a Wells-Dawson-type polyoxometalate (POM) cluster and its countraions. The higher MW PCL-POM self-assembled into nanosheets, while the lower MW PCL-POM assembled into nanotubes just by altering the ratio of water in the DMF-water mixed solvent system. The two nano-objects have a similar membrane structure in which a PCL layer is sandwiched by the two POM-based complex layers. The PCL layer in the nanosheets is semicrystalline, while the PCL layer in the nanotubes is amorphous. We further exploited this MW-dependence to self-assemble the nanotubes on the nanosheet edges to create complex tube-graft-sheet nano-objects. We found that the nanotubes nucleate on the four {110} faces of the PCL crystal and then further grow along the crystallographic b-axis of the PCL crystal. Our findings offer hope for the further development of nano-objects with increasing complexity.

The process of liner wear and the changing characteristics of the ability of crushing and grinding in the coal pulverizer are analyzed, a new type of cylinder liner is developed, which has a multi-step wave crest. The small balls on the liner are stuck by the steps, in this way, the wear of the liner wave crest is lightened, so it can keep a long-term stability, it also can take the balls to a reasonable height, increase the number of the balls which are taken by the wave crest and make the dropping points scattered, as result of that, it substantially increased the coal pulverizer's crushing and grinding efficiency; Also the wave crest of the liner can be dismantled from the base plate and individually replaced, so it made a great reduce in the material consumption of liner. The test shows that, with appropriate use of the balls, the liner can reduce the ball charge by 35-50%, reduce power consumption by 30-40%，it also can keep the coal pulverizer's output and improve milling fineness.

The results of phosphorus fractionation in the sediments from a contaminated river containing different aquatic plants, analyzed by solution 31P-NMR for Organic Phosphorus, showed that the concentration of Inorganic Phosphorus dominated in all species and Organic Phosphorus accounted for over 20% of Total Phosphorus. In general, orthophosphate was dominant in all the sampling sites. The proportion of Organic Phosphorus accounting for the Total Phosphorus in the sediments with different plant decreased in the following order: Paspalum distichum>Typha orientalis>Hydrilla verticillata. Phosphorus-accumulation ability of Paspalum distichum was obviously stronger than Typha orientalis and Hydrilla verticillata. The Organic Phosphorus was in aquatic plants dominated by humic-associated P (Hu-P), which converted to Inorganic Ohosphorus more significantly in submerged plants than in emerged plants. The sediment dominated by Paspalum distichum abundantly accumulated Organic Phosphorus in the orthophosphate monoester fraction. The degradation and mineralization of orthophosphate monoester was the important source of high Inorganic Phosphorus concentration and net primary productivity in Suoxu River. The Organic Phosphorus derived from Typha orientalis and Hydrilla verticillata was dramatically converted to Inorganic Phosphorus when the environmental factors varied.

Public participation has been one of important problems in the strategic environmental assessment (SEA). In this paper, the origin and the present research-conditions of public participation in SEA were analyzed. And the necessity of public participation was illuminated from following three aspects: 1) the public participation in China’s SEA is a key method of gaining the public support; 2) the public participation is one important source of gaining information; 3) the public participation is a good way to overcome the obstruction in the traditional mechanism of making strategy decision. Effective public participation should be involved in the whole process of SEA, and the public participators should include the public representatives of the groups affected by environmental change, the specialists in SEA and relevant fields, persons who are interested in the strategy and media, and so on. Various methods of public participation in SEA, including the methods of obtaining information and information feedback or consultation, were discussed. Further, the function, the advantages and the disadvantages of each method were discussed in detail, too.

Dental fluorosis (DF) is one of the important performances of endemic fluorosis. Some studies indicated that estrogen receptor (ESR) gene polymorphisms were associated with bone metabolism-related diseases. Therefore, it is possible that the variation in ESR genotypes will be associated with DF status. A case–control study was conducted among children aged 8–12 years with (n = 75) or without (n = 165) DF in China to investigate the relationship between ESR gene polymorphisms and DF. Gene polymorphisms were genotyped using the PCR-RFLP procedure. Children carrying R allele of ER RsaI had significantly increased risk of DF (Odds ratio (OR) = 1.821; 95% confidence interval (CI), 1.013–3.274) compared to children carrying r allele of ER RsaI in endemic fluorosis villages. For children with high-loaded fluoride status, carrying X allele of ESRα XbaI had a significantly decreased risk of DF (OR = 0.542; 95% CI, 0.314–0.936) compared to carrying x allele. This study provides the first evidence of an association between polymorphisms in the ESR gene with DF in high-fluoride-exposed populations. Further studies are needed to confirm the association.

High fluoride exposure can result in dental fluorosis. Fluoride and iodine are coexistent in the drinking water of areas in China and may affect the prevalence of dental fluorosis and osteogenesis. The aim of this study was to investigate the relationship between serum calciotropic hormone level, and dental fluorisis in children exposed to different concentrations of fluoride and iodine in drinking water.A pilot study was conducted in three villages located in the Kaifeng and Tongxu counties of Henan Province, China in 2006. Children aged 8 to 12 years, born and raised in the three villages were recruited. The fluoride levels in the samples of urine from these children were detected by fluoride ion selective electrode. Calcitonin and osteocalcin levels in the serum, and serum calcium were measured by radioimmunassay and flame atomic absorption spectrometry, respectively.Fluoride levels in urine were significantly lower in children from control area (CA) as compared with those from the high fluorideiodine areas (HFIA) and the high fluoride area (HFA) (P0.05 respectively), and no statistically significant difference was found between the children from HFIA and HFA. Additionally, calcitonin levels in the serum were significantly lower in children from CA and HFA as compared with that from HFIA (P0.05 respectively), and osteocalcin levels in the serum was lower in children from CA than those from HFIA (P0.05). No statistically significant difference in serum osteocalcin concentrations was found between children from HFA and HFIA.This study provides an evidence that iodine exposure may modify the serum calciotropic hormone levels related to fluorine exposure.

In April, May, August, and October 2006, grid-based sampling method was adopted to investigate the diversity and abundance of arthropods on 50 islands in the Thousand-island Lake, with the effects of island area, island altitude, island shape, inter-island distance, and island-mainland distance on arthropod species richness analyzed. With the increase of island area, the richness of total arthropod species and that of the arthropod species with high- and low- dispersal ability all increased, and the relationships between island area and arthropod species richness corresponded to the classical island biogeography model. The island area, island altitude, and island shape had comprehensive effects on the arthropod species richness, while inter-island distance and island-mainland distance had less effects. The richness of total arthropod species had a significant positive correlation with island altitude and island shape, that of the arthropod species with high- dispersal ability was significantly positively correlated with island area and island altitude, while no significant relationship was observed between the richness of arthropod species with low-dispersal ability and the island characteristics.

The objective of this work was to explore the potential of ultraflexible liposomes as carriers for improving the absorption of salmon calcitonin (sCT) through intranasal administration. The average diameters of positively charged ultraflexible liposomes ranged from about 73 to 99 nm, while those of negatively charged ones were 114 and 157.6 nm, respectively. The content of sodium deoxycholate in liposomes markedly affected the size and encapsulated efficiency of liposomes. The absorption of sCT through intranasal administration was evaluated by hypocalcemic efficacy in rats. The total Ca decrease D% of sCT-loaded ultraflexible liposomes with positive and negative charges were significantly bigger than that of sCT solution, while there was no significant difference in the hypocalcemic efficacy between plain liposome and sCT solution. Unexpectedly, the hypocalcemic efficacy of sCT-loaded ultraflexible liposomes with positive charges was not significantly better than those with negative charges. The decrease rate and extent of the serum calcium level for subcutaneous injection of sCT solution were almost equivalent to those for intranasal administration of negatively and positively charged ultraflexible liposomes within the first 2 h, indicating that the ultraflexible liposomes could quickly enhance the penetration of the drug during their residence in the nasal cavity. The results of the toxicity of sCT-loaded ultraflexible liposomes to nasal mucosa demonstrated that the ultraflexible liposomes exerted slight toxicity on the nasal mucosa. On an overall evaluation, the ultraflexible liposomes may be a useful vehicle for intranasal delivery of sCT.

Dysphagia is the main clinical symptom of the patients with esophageal carcinoma. The stent placement in esophagus is an effective method to resolve dysphagia.There are many types of stents. Through comparing observation of the stents made in China, which is the stainless steel "Z" stent, the Ni-Ti wire mesh-like stent, and the covered or uncovered-stent, the authors analyzed the clinical application of various types of esophageal stents in the treatment of malignant esophageal stricture.The various types of esophageal stents were implanted into 40 patients with esophageal carcinoma. 13 cases for stainless steel "Z" stents, 27 cases for Ni-Ti wire mesh-like stents(24 cases were the covered stents and 16 cases were uncovered). All the patients were not operated with the dilation of balloon before stent placement.The esophageal stents were successfully implanted into 40 patients without complication of operation. Stainless steel "Z" stent were all dilated immediately at the time of operation, and all the 13 patients had obvious intra-breastbone pain after operation, which lasted 10-20 days. Although Ni-Ti wire mesh-like stents could not dilate completely in operation, all these can be dilated completely after 1 to 3 days; nine cases of them had obvious intra-breastbone pain, which lasted 3-5 days. In all these, 7 cases were the covered-stents and 2 cases uncovered. In 9 cases, tracheoesophageal fistulas were blocked completely. There was barium sulphate retention between the covered-stent implanted to the patients without tracheoesophageal fistula and the dilated esophagus.The clinical adaptability of the Ni-Ti wire mesh-like stent is better than that of the stainless steel "Z" stent. For the patients with tracheoesophageal fistula, the first choice is covered-stent, while for the patients without tracheoesophageal fistula, uncovered-stent is better. The dilation of balloon is not necessary before the stent placement.

A series of monomethoxy poly(ethylene glycol)-poly(lactide) (mPEG-PLA) diblock copolymers were synthesized, and mPEG-PLA micelle was fabricated and used as a nanocarrier for solubilization and delivery of a promising anticancer drug ethaselen. Ethaselen was efficiently encapsulated into the micelles by the dialysis method, and the solubility of ethaselen in water was remarkably increased up to 82 μg/mL before freeze-drying. The mean diameter of ethaselen-loaded micelles ranged from 51 to 98 nm with a narrow size distribution and depended on the length of PLA block. In vitro hemolysis study indicated that mPEG-PLA copolymers and ethaselen-loaded polymeric micelles had no hemolytic effect on the erythrocyte. The enhanced antitumor efficacy and reduced toxic effect of ethaselen-loaded polymeric micelle when compared with ethaselen-HP-β-CD inclusion were observed at the same dose in H22human liver cancer cell bearing mouse models. These suggested that mPEG-PLA polymeric micelle nanoparticles had great potential as nanocarriers for effective solubilization of poorly soluble ethaselen and further reducing side effects and toxicities of the drug.