10 research outputs found

    Additional file 1 of The survival strength of younger patients in BCLC stage 0-B of hepatocellular carcinoma: basing on competing risk model

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    Additional file 1: Table S1. Baseline characteristics of study patients after propensity score analysis. Figure S1. The Kaplan-Meier survival curves of Overall survival (OS) and Progression-free survival (PFS) in BCLC 0-B group. (A-B) The OS (A) and PFS (B) in tumor size. (C-D) The OS (C) and PFS (D) in esophageal and/or gastric varices. (E-F) The OS (E) and PFS (F) Child staging A and B

    Modular Preparation of Discrete Polyesters through Iterative Growth

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    Discrete macromolecules featuring precise chemical structures and uniform chain lengths are ideal model systems for resolving fundamental principles with an exceedingly high resolution. This work develops a robust approach to prepare orthogonally protected monomers for the convergent synthesis of discrete sequence-defined polymers. Malic acid derivatives bearing hydrophilic, hydrophobic, or omniphobic substituents were designed and synthesized. All of these monomers have the same chemical features and can be modularly connected following the same chemistry. Discrete polyesters with diverse composition and programmable monomer sequence, including homopolymers, diblock/triblock copolymers, and alternating polymers, were readily prepared. The resultant discrete species were fully characterized by nuclear magnetic resonance (NMR) spectroscopy, size exclusion chromatography (SEC), and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF MS). This study expands the diversity of monomers that can be applied in iterative growth, which is expected to serve as an efficient synthetic platform for precise macromolecular engineering

    Extraction of Phenols from Water with Functionalized Ionic Liquids

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    A series of hydroxyl-, benzyl-, and dialkyl-functionalized ionic liquids (ILs) were synthesized, and their extraction abilities for phenol, resorcinol, <i>p</i>-nitrophenol, guaiacol, and <i>o</i>-cresol were investigated. Results showed that the extraction efficiencies of the five phenols were significantly influenced by the pH values, salt added, phase ratio, and chemical structure of the IL. Phenols present in nonionized forms were preferable to transfer into IL phases. The anion/cation hydrogen-bonding characters of ILs were the main structural factors affecting the extraction efficiency, which also increased with increased hydrophobicity of phenols. These results are promising for the liquid–liquid extraction and enrichment of phenols in separation science and related industrial processes

    Discrete Diblock Copolymers with Precise Stereoconfiguration

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    This work develops an iterative growth approach to synthesize discrete oligo lactic acids with exactly defined stereoconfiguration by connecting enantiomeric monomers (i.e., L- and D-lactic acid) following a predesigned sequence. A library of diblock copolymers with uniform chain length was modularly prepared by conjugating the stereoisomeric blocks with a chemically incompatible chain. The precise chemical structure eliminates all molecular uncertainties associated with statistical distribution and decouples the intertwined variables. A rich collection of ordered structures, including unconventional Frank–Kasper A15 and σ phases, was captured. The stereoconfiguration exerts pronounced impacts on chain conformation, leading to appreciable variations of lattice dimension and phase stability. This study quantitatively assessed the critical contribution of stereoconfiguration on packing behaviors, calling for particular attention to this essential molecular parameter as an effective handle for rational structural engineering

    Discrete Diblock Copolymers with Tailored Conformational Asymmetry: A Precise Model Platform to Explore Complex Spherical Phases

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    Conformational asymmetry of block copolymers is a critical molecular parameter dictating the self-assembly behaviors. This work develops an efficient approach to construct block copolymers with uniform chain length and tunable conformational mismatch. Three model discrete diblock copolymers based on γ-alkyl-α-hydroxy glutaric acid and lactide monomers were prepared through the iterative growth approach. The conformational asymmetry can be adjusted via simple substitution of the hydrocarbon side chains. The precise chemical structure rules out all molecular uncertainties associated with statistical distribution, providing a delicate platform for quantitatively resolving the intricate details and underlying principles. Diverse ordered structures, including the Frank–Kasper σ and A15 phases and quasicrystalline phase, were captured. A phase portrait with an exceptionally high compositional resolution was mapped, demonstrating clearly that the spherical packing region expands and the complex phases emerge as the conformational asymmetry increases. This study explicitly correlates the origin of the intriguing structures with the intrinsic molecular parameters, providing deep insights into the formation and evolution of the complex phases in block copolymers

    Modulation of the Complex Spherical Packings through Rationally Doping a Discrete Homopolymer into a Discrete Block Copolymer: A Quantitative Study

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    The Frank–Kasper phase and quasicrystalline phase are an intriguing class of complex crystalline structures, which so far are sporadically observed only in a limited number of block copolymers. Incorporation of a homopolymer into a block copolymer has recently been demonstrated as an effective and robust approach to regulate the formation and evolution of these complex spherical phases. The experimental explorations, however, suffer from inherent chain length distribution of the blending stocks. In this study, we quantitatively assessed the phase behaviors of the block copolymer/homopolymer binary blends using discrete species with a precise chemical structure and uniform chain length, ruling out all interferences associated with chemical heterogeneities. Diverse spherical packings, including σ, A15, C15, and C14 phases, were captured by rationally tuning the chain length and loading content of the homopolymer. The short chains swell the spherical core and drive a transition toward the lattices with a lower interfacial curvature (i.e., σ → A15 → HEX), whereas the long chains localize in the center of the core and prompt the formation of the Frank–Kasper phases with the increasing particle volume asymmetry (C15 and C14). The experimental observation validates the recent theoretical advances, demonstrating that the blending strategy is a robust approach for structural engineering

    Local Chain Feature Mandated Self-Assembly of Block Copolymers

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    This work demonstrates an effective and robust approach to regulate phase behaviors of a block copolymer by programming local features into otherwise homogeneous linear chains. A library of sequence-defined, isomeric block copolymers with globally the same composition but locally different side chain patterns were elaborately designed and prepared through an iterative convergent growth method. The precise chemical structure and uniform chain length rule out all inherent molecular defects associated with statistical distribution. The local features are found to exert surprisingly pronounced impacts on the self-assembly process, which have yet to be well recognized. While other molecular parameters remain essentially the same, simply rearranging a few methylene units among the alkyl side chains leads to strikingly different phase behaviors, bringing about (i) a rich diversity of nanostructures across hexagonally packed cylinders, Frank–Kasper A15 phase, Frank–Kasper σ phase, dodecagonal quasicrystals, and disordered state; (ii) a significant change of lattice dimension; and (iii) a substantial shift of order-to-disorder transition temperature (up to 40 °C). Different from the commonly observed enthalpy-dominated cases, the frustration due to the divergence between the native molecular geometry originating from side chain distribution and the local packing environment mandated by lattice symmetry is believed to play a pivotal role. Engineering the local chain feature introduces another level of structural complexity, opening up a new and effective pathway for modulating phase transition without changing the chemistry or composition

    Precisely Encoding Geometric Features into Discrete Linear Polymer Chains for Robust Structural Engineering

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    Molecular shape is an essential parameter that regulates the self-organization and recognition process, which has not yet been well appreciated and exploited in block polymers due to the lack of precise and efficient modulation methods. This work (i) develops a robust approach to break the intrinsic symmetry of linear polymers by introducing geometric features into otherwise homo­geneous chains and (ii) quantitatively highlights the critical contribution of molecular geometry/architecture to the self-assembly behaviors. Iteratively connecting homologous monomers of different side chains according to pre-designed sequences generates discrete polymers with exact chemical structure, uniform chain length, and programmable side-chain gradient along the backbone, which transcribes into diverse shapes. The precise chemistry eliminates all the defects and heterogeneities, providing a delicate platform for fundamental inquiries into the role of molecular geometry. A rich collection of unconventional complex phases, including Frank–Kasper A15 and σ phases, as well as a dodecagonal quasicrystal phase, were captured in these rigorous single-component systems. The self-assembly behaviors are strikingly sensitive to subtle variations of geometry, such that simply migrating a few methylene units among the side chains would generate substantial differences in lattice size or phase stability, or even trigger a phase transition toward distinct structures. The phenomena can be rationalized with a geometric argument that nonuniform side chain distribution leads to conformational mismatch between two immiscible blocks, resulting in varied interfacial curvatures and distinct lattice symmetries. The profound contribution demonstrates that molecular geometry is an effective and robust parameter for structural engineering

    Additional file 1 of Primary non-response to antiviral therapy affects the prognosis of hepatitis B virus-related hepatocellular carcinoma

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    Additional file 1: Supplementary Table 1. Demographic data and clinical characteristics of the patients after the 1:3 PSM. Supplementary Figure 1. Kaplan-Meier curve showing 1-year overall survival (OS) in the two groups. Supplementary Figure 2. Subgroup analysis according to tumor stage and treatment modality

    Discrete Linear–Branched Block Copolymer with Broken Architectural Symmetry

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    Rationally introducing chain length heterogeneity, such as binary blending, is a robust approach to regulate phase behavior of block copolymers. This work designed a library of discrete linear–branched block copolymers bearing two unequal branches. Diverse ordered nanostructures, including complex Frank–Kasper phases and quasicrystalline phase, were captured by tuning the compositional and architectural asymmetry. The precise chemistry rules out the interferences associated with statistical distribution, while the discrete feature decouples the intertwined variables. Compared with the symmetric counterparts, the synergies between the long and short chains effectively release the packing frustration during the formation of ordered structures, leading to a significant increase of lattice dimension and phase stability. The “built-in” chain length heterogeneity circumvents the shortcomings encountered by the conventional blending strategy, providing an excellent alternative for quantitatively assessing the effect of molecular symmetry on the self-assembly behaviors of block copolymers
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