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Integrating adaptative logic computation directly into soft microrobots is imperative for the next generation of intelligent soft microrobots as well as for the smart materials to move beyond stimulus‐response relationships and toward the intelligent behaviors seen in biological systems. Acquiring adaptivity is coveted for soft microrobots that can adapt to implement different works and respond to different environments either passively or actively through human intervention like biological systems. Here, a novel and simple strategy for constructing untethered soft microrobots based on stimuli‐responsive hydrogels that can switch logic gates according to the surrounding stimuli of environment is introduced. Different basic logic gates and combinational logic gates are integrated into a microrobot via a straightforward method. Importantly, two kinds of soft microrobots with adaptive logic gates are designed and fabricated, which can smartly switch logic operation between AND gate and OR gate under different surrounding environmental stimuli. Furthermore, a same magnetic microrobot with adaptive logic gate is used to capture and release the specified objects through the change of the surrounding environmental stimuli based on AND or OR logic gate. This work contributes an innovative strategy to integrate computation into small‐scale untethered soft robots with adaptive logic gates. [ABSTRACT FROM AUTHOR]

Background: Adolescent endometriosis is a special type of endometriosis. Its diagnosis is often delayed. This study aimed to share the treatment experience of adolescent endometriosis and analyze the clinical manifestation, clinical stage, and risk factors of postoperative recurrence in China. Methods: Eighty‐nine cases of adolescent endometriosis over 7 years in a single institution were reviewed. Demographic, clinical outcome measures were collected. Result: The cumulative incidence rates of postoperative recurrence at years 1, 2, 3, 4, and 5 were 13.2%, 15.09%, 16.98%, 20.75%, and 20.75%, respectively. The risk factors associated with postoperative recurrence were disease stage, number of lesions, and height. In multivariate analysis, the independent risk factors of postoperative recurrence were height (RR: 1.132, 95% CI: 1.018–1.260) and the number of pelvic lesions (three or more, RR: 4.202, 95% CI: 1.013–17.433). Conclusion: Taller patients and those who had multiple lesion sites (≥3) should receive more attention, because they have a higher possibility of relapse after surgery than their counterparts. This finding can guide the postoperative treatment of adolescent patients with endometrioma. [ABSTRACT FROM AUTHOR]

This paper presents the first causal evidence that compulsory education improves retirement financial outcomes in a developing economy. By exploiting the 1986 compulsory schooling reform in China, we show that compulsory education increases rural residents' participation in the New Rural Pension Scheme, the world's largest public pension program. Using an instrumental variables strategy in a difference‐in‐differences framework, we find that an additional year of schooling significantly increases pension participation by 3.5 percentage points, and this positive result is more prominent among women. Mechanism analysis suggests that cognition and access to information are essential pathways in the education–pension nexus. [ABSTRACT FROM AUTHOR]

Electrospun nanofibers from copolymers composed of ferrocene side chains and PEO100‐PPO65‐PEO100 (F127) were fabricated in chloroform and N,N–dimethyl formamide solutions (V/V = 95:5) at room temperature. Ferrocene‐containing multiblock copolymers (PFcMAn‐F127‐PFcMAn) were synthesized through reversible addition‐fragmentation chain transfer polymerization using s‐1‐dodecyl‐s''‐ (α, α'‐dimethyl‐α''‐acetic acid) trithiocarbonate (DDMAT) modified F127 with 2‐ (methacryloyloxy) ethyl ferrocencarboxylate (FcMA). The structures of as‐obtained chemicals were characterized by FTIR, 1H NMR, and 13C NMR. Additionally, the block copolymers molecular weight and polydispersity were measured using gel permeation chromatography. The electrochemical responsiveness of the polymers was investigated using cyclic voltammetry as well as the thermal stabilities of polymers and precursors were tested through DSC and TGA. The morphologies of electrospun fibers were observed through field emission scanning electronic spectroscopy and a fibrous diameter of 300–1100 nm was obtained. The results indicated that the suitable molecular weight of ferrocene ‐containing polymer would be processed in nanofibrous. [ABSTRACT FROM AUTHOR]

Teacher innovation is closely related to the improvement of basic education quality, and the cultivation of innovative talent for the nation. However, few studies have employed the causes of teacher innovation from the perspective of intrinsic motivation. To explore the factors and mechanisms affecting teacher innovation, we surveyed 421 middle school teachers to investigate the mediating roles of organizational identification and work engagement in the relationship between career calling and teacher innovation. The results indicate that career calling has a significantly positive impact on teacher innovation and that both organizational identification and work engagement mediate the effect of career calling on teacher innovation. Moreover, organizational identification and work engagement act as chain mediators in the relationship between career calling and teacher innovation. Therefore, to promote teacher innovation in middle school, it is important to emphasize the sense of calling, organizational identification, and work engagement. Practical implications for how to promote teacher innovation are also discussed. [ABSTRACT FROM AUTHOR]

Self‐assembly and supramolecular inclusion complexations between telechelic polymers bearing one or double adamantane groups and linear poly(β‐cyclodextrin) (P(β‐CD)) were investigated in water. An adamantane (Ada) attached to poly (acrylic acid) (PAA) was prepared by reversible addition‐fragmentation chain transfer polymerization using s‐1‐dodecyl‐s″ ‐(α,α′‐dimethyl‐α″‐acetic acid) trithio‐carbonate functionalized Ada with tert‐butyl acrylate, followed by functional modification. Additionally, two Ada groups capped triblock copolymer F127 were obtained via an esterification reaction. The dynamic light scattering, transmission electron microscope and 1H 2D NOSEY NMR spectroscopy were conducted to characterize the self‐assembly behaviors. With the inclusion complexation of Ada/CD in 1:1 M ratio in water, the spherical micelles were enlarged at 25°C than that of the adamantyl polymer precursors. Due to the PPO segment of Ada‐F127‐Ada, the micelles aggregation showed temperature dependence from 4 to 37°C for precursor and corresponding inclusion complexation; while in Ada‐PAA/P(β‐CD) system, the hydrodynamic diameters decreased with pH decreasing. [ABSTRACT FROM AUTHOR]

This article considers a bivariate INAR(1) process based on an extension of the negative binomial thinning operator by prespecifying the distribution of the innovations. The dependence is introduced through the innovation components. The existence, uniqueness, strict stationarity, ergodicity, and some probabilistic properties of the process are derived. The estimation methods of conditional least squares and conditional maximum likelihood are considered. Some numerical results of the estimates are presented by simulation study. An application to crime data set is provided. [ABSTRACT FROM AUTHOR]

An effective method for the synthesis of benzazoles through the electrochemical oxidative cyclization of o‐aminophenol/o‐aminothiophenol/o‐phenylenediamine and aldehydes was developed. A series of benzazoles were efficiently synthesized by using this method in good yields. Furthermore, this method was applied to the synthesis of the drug thiabendazole in a gram‐scale reaction, which proved the practicality of the method. This approach avoids using catalysts and oxidants, and has the advantages of wide substrate range, mild reaction conditions and good tolerance of functional groups. Finally, the possible reaction mechanism was proposed and supported by cyclic voltammetry (CV) and control experiments. [ABSTRACT FROM AUTHOR]

An electrochemical direct ortho‐hydroxylation of 2‐aryl‐4H‐benzo[e][1,3]oxazin‐4‐ones was developed with Pd(OAc)2 as catalyst, oxazine ring as a directing group and Oxone as the hydroxylation reagent. A series of hydroxylation products were obtained under mild conditions, and the yields were from medium to good. This method is characterized by good functional group tolerance and a wide range of substrates. More importantly, use anodic oxidation to avoid the use of potentially toxic and polluting oxidants. A gram‐scale direct electrochemical hydroxylation of 2‐phenyl‐4H‐benzo[e][1,3]oxazin‐4‐one was performed, and the hydroxylation product was applied to synthesize the drug deferasirox. In addition, the single crystal of 2‐(2‐hydroxyphenyl)‐4H‐benzo[e][1,3]oxazin‐4‐one was obtained and determined by X‐ray diffraction. Finally, the reaction mechanism was proposed and verified by cyclic voltammetry (CV). This protocol also provides an alternative electrochemical hydroxylation methodology for the functionalization of molecules. [ABSTRACT FROM AUTHOR]

Abstract: Fluorescent supramolecular polymers are an important kind of smart material. In this work, a new fluorescent supramolecular hyperbranched polymer (FSHP) is constructed by orthogonal self‐assembly: pillararene‐based host–guest interaction and metal ion complexation interaction. The FSHP exhibits concentration‐controllable fluorescence emissions. The photoluminescence spectra and light‐emitting colors of FSHP can be effectively tuned by changing metal ion types or using mixed metal ions. The fluorescence quenching of FSHP solutions or FSHP‐based films would occur when removing the metal ions from the backbone of FSHP. This study supplies a convenient approach toward the construction of structure‐tunable fluorescent supramolecular materials with different colors. [ABSTRACT FROM AUTHOR]

Supramolecular copolymers can not only enrich the diversity of the polymer backbone but also exhibit certain special and improved properties compared with supramolecular homopolymers. However, the synthesis procedure of supramolecular copolymers is relatively complicated and time-consuming. Herein, a simple transformation from an AB2-based supramolecular hyperbranched homopolymer to an AB2+CD2-based supramolecular hyperbranched alternating copolymer by the 'competitive self-sorting' strategy is reported. After adding CD2 monomer, which bears a competitive neutral guest moiety ( TAPN) and two receptive benzo-21-crown-7 host moieties ( B21C7), to the as-prepared AB2-type supramolecular hyperbranched homopolymer constructed by the self-assembly of dialkylammonium salt ( DAAS, A group)-functionalized pillar[5]arene ( MeP5, B groups) monomers, the initial homopolymer structure is disrupted and then reassemble into a new supramolecular hyperbranched alternating copolymer based on the competitive self-sorting interaction between MeP5- TAPN and B21C7- DAAS. This study supplies a convenient approach to directly transform supramolecular homopolymers into supramolecular copolymers. [ABSTRACT FROM AUTHOR]

The azide-alkyne 'click' reaction has been well known in the past decade, however, another kind of 1,3-dipolar cycloaddition, the azide-alkene reaction is not fully explored in polymer science to date. This contribution reports, for the first time, the discovery of a polyaddition of norbornene based monomer (NC11N3) containing both strained double bond and azide moieties. The reaction product is characterized by Fourier transform infrared spectroscopy (FTIR), NMR, gel permeation chromatography (GPC), and mass spectrometry (MS), which confirmed the mechanism that is through cycloaddition of azide to strained double bond on norbornene ring to form triazoline linkage. The reaction can proceed at room temperature as indicated by the increase of molecular weight and viscosity during storage. Monomer, dimer, trimer, tetramer, etc., and species with loss of N2 due to lability of triazoline moiety are identified in the mixture of reaction product. As a unique feature, elimination of N2 in the five-membered ring of triazoline affords a chance to form highly reactive materials, such as with aziridine, which can be a very powerful tool in chemical functionalizations, and find promising applications in reactive polymer resin industries. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel aromatic acetal-based acid-labile monomer 2-phenyl-5-ethyl-5-acryloxymethyl-1,3-dioxacyclohexane (HEDPA) was synthesized and polymerized by reversible addition fragmentation chain transfer (RAFT) polymerization using alkynyl functional chain transfer agent (CTA-Alk). Afterward, a series of amphiphilic diblock copolymers composed of fixed hydrophobic poly(2-phenyl-5-ethyl-5-acryloxymethyl-1,3-dioxacyclohexane) (PDAEP) segments and various lengths of hydrophilic mPEG segments were prepared through click reaction between alkynyl-terminated PDAEP and azido-terminated mPEG. The self-assembly behaviors of the diblock copolymers were investigated by dynamic light scattering (DLS), transmission electron microscopy (TEM), fluorescence spectroscopy, and 1H NMR. These results indicated that the diblock copolymers could self-assemble into nano-sized micelles with PDAEP cores and PEG coronas in aqueous solution. DLS, fluorescence spectroscopy and UV-vis spectroscopy were used to monitor the pH-triggered assembly/disassembly transition of the micelles. These results showed that the assembly/disassembly transition behaviors of the diblock copolymers micelles can be adjusted by changing the lengths of the mPEG segments. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1537-1547 [ABSTRACT FROM AUTHOR]

Study Type - Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? This study showed that tubeless PCNL could reduce hospital stay with little need for postoperative analgesia. This study discussed the clinical feasibility of tubeless PCNL, which is the tendency of PCNL. Our results are reliable by using veta-analysis from individual studies. OBJECTIVE [ABSTRACT FROM AUTHOR]

We report the synthesis and gradient stimuli-responsive properties of cyclodextrin-overhanging hyperbranched core-double-shell miktoarm architectures. A ionic hyperbranched poly(β-cyclodextrin) (β-CD) core was firstly synthesized via a convenient 'A2+B3' approach. Double-layered shell architectures, composed of poly( N-isopropyl acrylamide) (PNIPAm) and poly( N,N-dimethylaminoethyl methacrylate) (PDMAEMA) miktoarms as the outermost shell linked to poly( N,N-diethylaminoethyl methacrylate) (PDEAEMA) homoarms which form the inner shell, were obtained by a sequential atom transfer radical polymerization (ATRP) and parallel click chemistry from the modified hyperbranched poly(β-CD) macroinitiator. The combined characterization by 1H NMR, 13C NMR, 1H-29Si heteronuclear multiple-bond correlation (HMBC), FTIR and size exclusion chromatography/multiangle laser light scattering (SEC/MALLS) confirms the remarkable hyperbranched poly(β-CD) core and double-shell miktoarm architectures. The gradient triple-stimuli-responsive properties of hyperbranched core-double-shell miktoarm architectures and the corresponding mechanisms were investigated by UV-vis spectrophotometer and dynamic light scattering (DLS). Results show that this polymer possesses three-stage phase transition behaviors. The first-stage phase transition comes from the deprotonation of PDEAEMA segments at pH 9-10 aqueous solution under room temperature. The confined coil-globule conformation transition of PNIPAm and PDMAEMA arms gives rise to the second-stage hysteretic cophase transition between 38 and 44 °C at pH 10. The third-stage phase transition occurs above 44 °C at pH = 10 attributed to the confined secondary conformation transition of partial PDMAEMA segments. This cyclodextrin-overhanging hyperbranched core-double-shell miktoarm architectures are expected to solve the problems of inadequate functionalities from core layer and lacking multiresponsiveness for shell layers existing in the dendritic core-multishell architectures. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Poly(ethylene glycol) (PEG) is an important water-soluble polymer, which is widely used in the biomedical field because of its good biodegradability, biocompatibility and permeability. It is usually synthesized by anionic polymerization of ethylene oxide but side reactions lead to the formation of some oligomers. High molecular weight PEG can be obtained, however, through coordinated anionic polymerization. Recently a novel controlled anionic polymerization based on the initiating system ammonium bromide/trialkylaluminium was reported. Related studies have shown that the controlled anionic polymerization allows the synthesis of linear polyethers with low dispersity in a wide range of molecular weights at ambient temperature. Unfortunately, so far this controlled anionic polymerization has not been used to synthesize polymers with complex architectures. In the work reported here, controlled anionic polymerization was combined with 'click' chemistry for the first time to synthesize polyethers with multiple arms. Firstly, controlled anionic polymerization was employed to synthesize a linear bromine-terminated PEG (PEG-Br) using ethylene oxide as the monomer and tetraoctylammonium bromide/triisobutylaluminium as the initiating system at room temperature. The terminal bromine in the PEG thus synthesized was then converted into an azide group by the reaction of PEG-Br and sodium azide. A trifunctional linking agent was also prepared by the reaction of trimethylolpropane and propiolic acid. By using 'click' chemistry, a three-arm PEG was finally obtained through the reaction of the azide-terminated PEG and the trifunctional linking agent. The chemical structure of the polymer thus synthesized was characterized using infrared spectroscopy, NMR spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and size-exclusion chromatography with multi-angle laser light scattering. It was found that the synthesized polyether possesses the designed structure. Considering the wide applicability of controlled anionic polymerization and 'click' chemistry, their combination is a valuable way to synthesize various polyethers with multiple arms. Copyright © 2009 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, a new strategy to synthesize random and alternating multiblock copolymers (MBCs) by the polycondensation of macromonomers' terminal hydroxyl groups with [CpRu(CH3CN)3]PF6/quinaldic acid as the catalyst is reported, which is often used for the preparation of a variety of biological small molecules via the reaction of allyl ethers. The degrees of hydroxyl functionality (Fn) of the MBCs are assessed by titration, and the presence of hydroxyl on both the ends of MBCs is also confirmed by a chain‐extension experiment of the ring‐opening polymerization of D,L‐lactide. [ABSTRACT FROM AUTHOR]

A novel Ni‐based initiator is designed and synthesized for obtaining a hydroxyl‐terminated polybutadiene (HTPB) with higher cis‐1,4 unit content (≥90%). By investigating the effect of the butadiene skeleton structure and counterion on initiating efficiency, it is found that [η3‐Ni(CH2CHCHCH2OOCH3)][BPhF4] complex is a feasible combination to be used as an initiator. 1H‐NMR data prove that the initiator structure obtained is in accordance with the original design. The result of 1H‐NMR, 13C‐NMR, FT‐IR confirms that HTPB synthesized not only gains a significant amount in cis‐1,4 unit content (≥90%) compared with the HTPBs by free radical and anionic polymerizations, but also its molecular weight and molecular weight distribution can be effectively controlled during synthesis process. Because of the much higher cis‐1,4 unit content, the glass‐transition temperature of HTPB obtained via [η3‐Ni(CH2CHCHCH2OOCH3)][BPhF4] is markedly reduced; as a result, its low‐temperature mechanical property can also be significantly improved. A novel Ni‐based initiator Ni(CH2CHCHCH2OOCH3)][BPhF4] is designed and synthesized for obtaining a hydroxyl‐terminated polybutadiene (HTPB) with higher cis‐1,4 unit content (≥90%). The glass‐transition temperature of HTPB obtained via [η3‐Ni(CH2CHCHCH2OOCH3)][BPhF4] is markedly reduced; as a result, its low‐temperature mechanical property can also be significantly improved. [ABSTRACT FROM AUTHOR]

Front Cover: Controlled supramolecular architecture transformation from supramolecular hyperbranched homopolymer to alternating copolymer was successfully achieved by “competitive self‐sorting” assembly. The supramolecular hyperbranched homopolymer was initially constructed by the self‐assembly of dialkylammonium salt (DAAS)‐functionalized pillar[5]arene (MeP5) AB2 monomers. After adding CD2 monomer to the AB2 system, the initial supramolecular hyperbranched homopolymer was disrupted and then reassembled into a new supramolecular hyperbranched alternating copolymer. Further information can be found in article 1600631, by H. Li, X. D. Fan,* X. Min, Y. C. Qian, and W. Tian*. [ABSTRACT FROM AUTHOR]

Front Cover: A polymer with triazoline located in the backbone is synthesized by polyaddition of an azide‐containing norbornene‐based monomer through a strain‐promoted cycloaddition reaction without any catalyst. As a unique feature, elimination of N2 from the five‐membered ring of triazoline caused by light or heat affords a chance to form a highly reactive polymer, such as with aziridine moieties, which may find promising applications in the industrial production of reactive polymer resins. Further details can be found in the article by X. J. Zhang, Q. Zhang,* Y. Z. Wu, C. Feng, C. Xie, X. D. Fan, and P. F. Li on page 1311. [ABSTRACT FROM AUTHOR]