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1D flexible fibers assembled 3D porous networked ceramic fiber aerogels (CFAs) are developed to overcome the brittleness of traditional ceramic particle aerogels. However, existing CFAs with disordered and quasi-ordered structures fail to balance the relationship between flexibility, robustness, and thermal insulation. Creating novel architectural CFAs with an excellent combination of performances has proven extremely challenging. In this paper, a novel strategy is adopted to fabricate porous mullite fibrous aerogels (MFAs) with ordered structures by combining fiber sedimentation and electric field-induced fiber alignment techniques. For the first time, electric field-induced alignment of ceramic fibers is utilized to prepare bulk aerogels on a large scale. The resulting MFAs exhibit ultra-low high-temperature thermal conductivity of 0.0830 W m-1 K-1 at 1000 °C, anisotropic mechanical and sound absorption performances, and multifunctionality in terms of the combination of thermal insulation, sound absorption, and hydrophobicity. The successful synthesis of such fascinating materials may provide new insights into the design and development of multifunctional CFAs for various applications.
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Keratin and lipid structures in the stratum corneum (SC) are closely related to the SC barrier function. The application of penetration enhancers (PEs) disrupts the structure of SC, thereby promoting infiltration. To quantify these PE-induced structural changes in SC, we used confocal Raman imaging (CRI) and polarized Raman imaging (PRI) to explore the integrity and continuity of keratin and lipid structures in SC. The results showed that water is the safest PE and that oleic acid (OA), sodium dodecyl sulfate (SDS), and low molecular weight protamine (LMWP) disrupted the ordered structure of keratin, while azone and liposomes had less of an effect on keratin. Azone, OA, and SDS also led to significant changes in lipid structure, while LMWP and liposomes had less of an effect. Establishing this non-invasive and efficient strategy will provide new insights into transdermal drug delivery and skin health management.
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Lipossomos , Pele , Lipossomos/farmacologia , Epiderme , Ácido Oleico/farmacologia , QueratinasRESUMO
This document introduces methods for describing long texts as groups of repeating symbols or patterns. The process converts a series of real-number values into texts. Developed tailored algorithms for identifying repeated sequences in the text are applied to decompose the text into nested tree-like structures of repeating symbols and is called the Nested Repeated Sequence Decomposition Model (NRSDM). The NRSDM is especially valuable for extracting repetitive behaviors in oscillatory but non-periodic and chaotic processes where the classical Fourier transform has limited application. The NRSDM along with the two graphical representations proposed here form a promising tool for characterizing long texts configured to represent the behavior of unidimensional processes.
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Starch is a major part of the human diet and an important material for industrial utilization. The structure of starch granules is the subject of intensive research because it determines functionality, and hence suitability for specific applications. Starch granules are made up of a hierarchy of complex structural elements, from lamellae and amorphous regions to blocklets, growth rings and granules, which increase in scale from nanometers to microns. The complexity of these native structures changes with the processing of starch-rich ingredients into foods and other products. This review aims to provide a comprehensive review of analytical methods developed to characterize structure of starch granules, and their applications in analyzing the changes in starch structure as a result of processing, with particular consideration of the poorly understood short-range ordered structures in amorphous regions of granules.
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Alimentos , Amido , Humanos , Amido/químicaRESUMO
Obtaining high ordered structure (HOS) information is of importance to guarantee the efficacy and safety of monoclonal antibodies (mAbs) in clinical application. Assessment of HOS should ideally be performed in a non-invasive manner under their formulated storage conditions, as any perturbation can introduce unexpected detritions. However, most of the currently available techniques only indirectly report HOS of mAbs and/or require a certain condition to conduct the analyses. Besides, the flexible multidomain architecture of mAbs has hampered atomic-resolution structural analyses using X-ray crystallography and cryo-electron microscopy. In contrast, the ability of nuclear magnetic resonance (NMR) spectroscopy to structurally analyze biomolecules in various conditions in a non-invasive and quantitative manner is suitable to meet the needs. However, the application of NMR to mAbs is not straightforward due to the high molecular weight of the system. In this review, we will discuss how NMR techniques have been applied to HOS analysis of mAbs, along with the recent advances of the novel 15N direct detection NMR strategy that allows for obtaining the structural fingerprint of mAbs at lower temperatures under multiple formulation conditions. The potential application of these NMR strategies will benefit next-generation mAbs, such as antibody-drug conjugates and bispecific antibodies.
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Anticorpos Monoclonais/química , Espectroscopia de Ressonância Magnética/métodos , Modelos Moleculares , Conformação Proteica , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/ultraestrutura , Microscopia Crioeletrônica , Cristalografia por Raios X , Glicosilação , Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/metabolismo , Fragmentos Fc das Imunoglobulinas/ultraestrutura , Imunoglobulina G/química , Imunoglobulina G/metabolismo , Imunoglobulina G/ultraestrutura , Estabilidade ProteicaRESUMO
The microscopic structures of ThF4-LiF and ThF4-LiF-BeF2 molten salts have been systematically investigated by in situ high-temperature X-ray absorption fine-structure (XAFS) spectroscopy combined with molecular-dynamics (MD) simulations. The results reveal that the local structure of thorium ions was much more disordered in the molten state of the ThF4-LiF-BeF2 salt than that in ThF4-LiF, implying that the Th and F ions were exchanged more frequently in the presence of Be ions. The structures of medium-range-ordered coordination shells (such as Th-F2nd and Th-Th) have been emphasized by experimental and theoretical XAFS analysis, and they play a significant role in transport properties. Using MD simulations, the bonding properties in the molten ThF4-LiF and ThF4-LiF-BeF2 mixtures were evaluated, confirming the above conclusion. This research is, to the best of our knowledge, the first systematic study on the ThF4-LiF-BeF2 molten salt via quantitative in situ XAFS analysis and MD simulations.
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Chemical energy supplied by the catalytic decomposition of H2O2 is introduced into macroscopic building blocks, which self-propel, interact with each other, and finally assemble into ordered and advanced structures. The geometry is highly dependent on the way that the catalyst is loaded. The integration of catalyst and building block provides assembling component as well as its energy of motion.
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Optically active through-space conjugated oligomers, namely, a dimer, trimer, tetramer, and cyclic trimer, consisting of a planar-chiral [2.2]paracyclophane skeleton were synthesized. In the ground state, observed similarities in the chiroptical properties of the oligomers were attributed to the equivalent orientations of two adjacent chromophores. In the excited state, the oligomers were folded into a form analogous to a one-handed helix by photoexcitation. All the compounds in dispersed solution exhibited intense circularly polarized luminescence with relatively large anisotropy factors on the order of 10(-3).
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Starch-polyphenol V-type inclusion complex has become a hot topic due to its anti-digestibility and nutritional function. This paper aimed to explore the molecular motion behavior of starch affects starch-polyphenol inclusion complex and digestibility among different stilbene polyphenol structures (resveratrol (RA), pterostilbene (PB) and polydatin (PD) via the high-pressure homogenization (HPH) and heat moisture treatment (HMT) processes), which represented the fully extended and limited molecular motion behavior of starch, respectively. These results revealed distinct trends in complex formation among different stilbenes polyphenol structures, highlighting RA as particularly conducive to increasing single helix and V-type crystalline structures with the highest resistant starch (RS) content of 28.11 % due to its smaller steric hindrance. Novelty, in HPH environments with extended molecular motion behavior, the steric hindrance and hydrophobicity/CH-π interactions of polyphenols influence complex formation in the order of RA > PB > PD. Conversely, in HMT systems with limited molecular motion behavior, the limited movement of molecules emphasized the importance of hydrogen bond interactions between polyphenols and starch. Thus, the glucoside in PD enhanced its interaction with starch compared to methoxy-modified PB, leading to increased formation of inclusion complex with RS content of 18.61 %. Overall, these findings deepen the understanding of starch-polyphenol interactions.
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Polifenóis , Amido , Estilbenos , Amido/química , Estilbenos/química , Polifenóis/química , Glucosídeos/química , Ligação de HidrogênioRESUMO
Recently, pre-formed V-type starch has become popular as a versatile carrier in encapsulation systems of containing starch-guest inclusion complexes (ICs). However, the differences in stabilizing and dissociating guests between ICs prepared by either the traditional method or the pre-formed "empty" helix method have not yet been elucidated. Here, starch-thymol ICs were prepared using the traditional high temperature-water method and the pre-formed method, covering different complexation temperatures and solvents, to compare the loading capacity, crystalline structure, thermal stability, and release properties. The highest content of thymol in ICs prepared by the pre-formed and the traditional method was 74.2 and 65.3 mg/g, respectively. Different from ICs prepared by the traditional method (V7-type crystal), ICs prepared by the pre-formed method mostly exhibited a V6a structure with larger crystallinities and a better short-range ordered structure. ICs prepared at 90 °C were type II complexes and efficiently protected thymol from rapid heat loss. A slow release was observed in both cases: about 45 % and 75 % of thymol were released from ICs prepared by the pre-formed and traditional methods, respectively, after two weeks of storage at 25 °C.
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This study aimed to investigate alterations in gut microbiota and metabolites mediated by wheat-resistant starch and its repair of gut barrier dysfunction induced by a high-fat diet (HFD). Structural data revealed that chlorogenic acid (CA)/linoleic acid (LA) functioned through noncovalent interactions to form a more ordered structure and fortify antidigestibility in wheat starch (WS)-CA/LA complexes; the resistant starch (RS) contents of WS-CA, WS-LA, and WS-CA-LA complexes were 23.40 ± 1.56%, 21.25 ± 1.87%, and 35.47 ± 2.16%, respectively. Dietary intervention with WS-CA/LA complexes effectively suppressed detrimental alterations in colon tissue morphology induced by HFD and repaired the gut barrier in ZO-1 and MUC-2 levels. WS-CA/LA complexes could augment gut barrier-promoting microbes including Parabacteroides, Bacteroides, and Muribaculum, accompanied by an increase in short-chain fatty acids (SCFAs) and elevated expression of SCFA receptors. Moreover, WS-CA/LA complexes modulated secondary bile acid metabolism by decreasing taurochenodeoxycholic, cholic, and deoxycholic acids, leading to the activation of bile acid receptors. Collectively, this study offered guiding significance in the manufacture of functional diets for a weak gut barrier.
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Ácido Clorogênico , Dieta Hiperlipídica , Microbioma Gastrointestinal , Ácido Linoleico , Camundongos Endogâmicos C57BL , Amido , Triticum , Ácido Clorogênico/metabolismo , Ácido Clorogênico/farmacologia , Ácido Clorogênico/administração & dosagem , Ácido Clorogênico/química , Dieta Hiperlipídica/efeitos adversos , Triticum/química , Triticum/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Masculino , Camundongos , Amido/metabolismo , Amido/química , Ácido Linoleico/metabolismo , Ácido Linoleico/química , Bactérias/classificação , Bactérias/metabolismo , Bactérias/genética , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Humanos , Ácidos Graxos Voláteis/metabolismo , Amido Resistente/metabolismoRESUMO
Allergic reactions can profoundly influence the quality of life. To address the health risks posed by allergens and overcome the permeability limitations of the current filter materials, this work introduces a novel microhoneycomb (MH) material for practical filter applications such as masks. Through a synthesis process integrating ice-templating and a gas-phase post-treatment with silane, MH achieves unprecedented levels of moisture resistance and mechanical stability while preserving the highly permeable microchannels. Notably, MH is extremely elastic, with a 92% recovery rate after being compressed to 80% deformation. The filtration efficiency surpasses 98.1% against pollutant particles that simulate airborne pollens, outperforming commercial counterparts with fifth-fold greater air permeability while ensuring unparalleled user comfort. Moreover, MH offers a sustainable solution, being easily regenerated through back-flow blowing, distinguishing it from conventional nonwoven fabrics. Finally, a prototype mask incorporating MH is presented, demonstrating its immense potential as a high-performance filtration material, effectively addressing health risks posed by allergens and other harmful particles.
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The past decade has witnessed the advances of infrared (IR) thermal camouflage materials, but challenges remain in breaking the trade-off nature between emissivity and mechanical properties. In response, we identify the key role of a moderate reprotonation rate in the aramid nanofiber (ANF)/MXene film toward a surface-to-bulk alignment. Theoretical simulation demonstrates that the ordered ANF/MXene surface eliminates the local high electric field by field confinement and localization, responsible for the low IR emissivity. By scrutinizing the surface/interface chemistry, the processing optimization is achieved to develop an ordered and densely stacked ANF/MXene film, which features a low emissivity of 16%, accounting for sound IR thermal camouflage performances including a wide camouflage temperature range of 50-200 °C, a large reduction in radiation temperature from 200.5 to 63.6 °C, and long-term stability. This design also enables good mechanical performance such as a tensile strength of 190.8 MPa, a toughness of 12.1 MJ m-3, and a modulus of 7.9 GPa, responsible for better thermal camouflage applications. The tailor-made ANF/MXene film further attains an electromagnetic interference (EMI) shielding effectiveness (40.4 dB) in the X-band, manifesting its promise for IR stealth compatible EMI shielding applications. This work will shed light on the dynamic topology reconstruction of camouflage materials for boosting thermal management technology.
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Herein, we proposed dry heat treatment (DHT) as a pre-treatment method for modifying printed materials, with a particular focus on its application in the control of starch-lipid interactions during hot-extrusion 3D printing (HE-3DP). The results showed that pre-DHT could promote the complexation of wheat starch (WS) and oleic acid (OA)/corn oil (CO) during HE-3DP and thus increase the resistant starch (RS) content. From the structural perspectives, pre-DHT could break starch molecular chains into lower relative molecular weight which enhanced the starch-lipids hydrophobic interactions to form the V-type crystalline structure during HE-3DP. Notably, pre-DHT could also induce the formation of complexed structure which was maintained during HE-3DP. Compared with CO, OA with linear hydrophobic chains was easier to enter the spiral cavity of starch to form more ordered structures, resulting in higher RS content of 27.48 %. Overall, the results could provide basic data for designing nutritional starchy food systems by HE-3DP.
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Temperatura Alta , Amido , Amido/química , Triticum/química , Amido Resistente , Impressão Tridimensional , Lipídeos/químicaRESUMO
Temperature-induced textural, cooking properties and structural variations of retrograded instant rice noodles (IRN) during the long-term storage were systematically investigated. IRN samples stored at 4 °C exhibited a relative high cooking loss (2.45 %), and their hardness values gradually increased with prolonged storage. Moreover, the higher storage temperature (35 °C) accelerated the deterioration of IRN texture. Fresh IRN displayed a typical B-type XRD pattern with 9.65 % relative crystallinity (RC). During the initial 2 weeks of storage, the formation of a long-range ordered structure led to an increase in RC, which was closely related to the duration and temperature of storage (ranging from 4 °C to 25 °C to 35 °C). Over the 12-week storage period, there was likely a disorganization of the supra-molecular structure, as evidenced by the considerably decreased RC and reduced water mobility. Furthermore, Pearson's correlation analysis highlighted that the tight integration between starch molecules and water molecules endowed IRN samples with enhanced smoothness and tenderness in flavor profiles. Hence, the study is expected to provide a comprehensive understanding of the mechanisms underlying molecular order changes in retrograded starch gel products during the long-term storage.
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Oryza , Oryza/química , Amido/química , Culinária , Farinha/análise , ÁguaRESUMO
Single-ion conductive polymer electrolytes can improve the safety of lithium ion batteries (LIBs) by increasing the lithium transference number (tLi+) and avoiding the growth of lithium dendrites. Meanwhile, the self-assembled ordered structure of liquid crystal polymer networks (LCNs) can provide specific channels for the ordered transport of Li ions. Herein, single-ion conductive nematic and cholesteric LCN electrolyte membranes (denoted as NLCN-Li and CLCN-Li) were successfully prepared. NLCN-Li was then coated on commercial Celgard 2325 while CLCN-Li was coated on poly(vinylidene fluoride-hexafluoropropylene) film, coupled with plasticizer, to make NLCN-Li/Cel and CLCN-Li/Pv quasi-solid-state electrolyte membranes, respectively. Their electrochemical properties were evaluated, and it was found that they possessed benign thermal stability and electrolyte/electrode compatibility, high tLi+ up to 0.98 and high electrochemical stability window up to 5.2 V. A small amount (0.5M) of extra Li salt added to the plasticizer could improve the ion conductivity from 1.79 × 10-5 to 5.04 × 10-4 S cm-1, while the tLi+ remained 0.85. The assembled LFP|Li batteries also exhibited excellent cycling and rate performances. The orderliness of the LCN layer played an important role in the distribution and movement of Li ions, thereby affecting the Li deposition and growth of Li dendrites. As the first report of nematic and cholesteric LCN single-ion conductors, this work sheds light on the design and fabrication of ordered quasi-solid-state electrolytes for high-performance and safe LIBs.
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In the biomedical fields of bone regenerative therapy, the immobilization of proteins on the bioceramic particles to maintain their highly ordered structures is significantly important. In this review, we comprehensively discussed the importance of the specific surface layer, which can be called "non-apatitic layer", affecting the immobilization of proteins on particles such as hydroxyapatite and amorphous silica. It was suggested that the water molecules and ions contained in the non-apatitic layer can determine and control the protein immobilization states. In amorphous silica particles, the direct interactions between proteins and silanol groups make it difficult to immobilize the proteins and maintain their highly ordered structures. Thus, the importance of the formation of a surface layer consisting of water molecules and ions (i.e., a non-apatitic layer) on the particle surfaces for immobilizing proteins and maintaining their highly ordered structures was suggested and described. In particular, chlorine-containing amorphous silica particles were also described, which can effectively form the surface layer of protein immobilization carriers. The design of the bio-interactive and bio-compatible surfaces for protein immobilization while maintaining the highly ordered structures will improve cell adhesion and tissue formation, thereby contributing to the construction of social infrastructures to support super-aged society.
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Polysaccharides are organic compounds widely distributed in nature, but structural order and disorder remain a formidable problem. In this study, based on the theoretical framework of the "relative ordered structure of polysaccharide" proposed in our previous work, the structural order of Hericium erinaceus polysaccharides from different regions was evaluated by FT-IR, methylation analysis, and 1H NMR spectroscopy combined with chemometric methods. The results of principal component analysis and heatmap cluster analysis revealed that 18-subfractions exhibit four different structural types with representative glycoside linkage types: fucogalactoglucan, glucofucogalactan, fucoglucan, and glucan. The main chain of heteroglucans often consists of ß-(1 â 6)-Glcp, ß-(1 â 4)-Glcp, and ß-(1 â 3)-Glcp residues, which are predominantly substituted at the O-3 and O-6 positions. The main chain structure of heterogalactans is α-(1 â 6)-Galp residues, which may be replaced by Fucp and Galp residues at O-2. Overall, our findings demonstrate the validity of the "relative ordered structure of polysaccharide" in Hericium erectus polysaccharides and simplify the complexity of polysaccharide structures.
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Hericium , Polissacarídeos , Espectroscopia de Infravermelho com Transformada de Fourier , Peso Molecular , Polissacarídeos/químicaRESUMO
In this study, the effects of starch- oleic acid (OA)- chlorogenic acid (CA) molecular interaction on OA oxidation during thermal processing were investigated based on structural analysis, oxidation characteristics and quantum calculations. The results showed that in the ternary system, on the one hand, OA could enter the spiral cavity of starch through hydrophobic forces and form V-type crystalline structure, which delayed its oxidation. On the other hand, CA could further inhibit the oxidation of OA through free radical reaction and did not affect the molecular interactions between OA and starch due to the steric hindrance and hydrophily. Notably, starch-OA-CA interactions could effectively decrease total oxidation value (19.07), prolong the induction time of oxidation (114.6 min) and reduce the abundance of oxidation products through hydrogen atom transfer reactions with active phenolic hydroxyl to protect the α-methylene groups at C=C. Overall, these results provided insights into functional property regulation by the interaction of starch-based multi-component systems.
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Ácido Clorogênico , Ácido Oleico , Radical Hidroxila , Oxirredução , AmidoRESUMO
Ceramic fiber aerogels are attractive thermal insulating materials. In a thermomechanical coupling environment, however, they often show limited mechanical strength and considerably increased heat transfer which can lead to thermal runaway. In this paper, inspired by bird's nest and nacre, we demonstrate a sample strategy combining fiber sedimentation and layer-by-layer assembly to fabricate ultrastrong mullite fiber aerogels (MFAs) with quasi-ordered structures. The fibrous layers and fiber bridges are constructed in a fiber sedimentation self-assembly process. The fiber sedimentation technique optimizes the structure of the MFAs by regulating the fiber orientation. Owing to the quasi-ordered structure, the fabricated MFAs exhibit the integrated properties of high compression fatigue resistance, temperature-invariant compression resilience from -196 to 1300 °C, and low thermal conductivity (0.034 W·m-1·K-1). By deliberately pressing multilayer MFAs into a thin paper, we substantially enhance the load-bearing capacity of the MFAs and achieve large temperature differences (563 °C) between the cold and hot surfaces by using a thin layer of MFAs (3-5 mm) under the simulated high-temperature (685 °C) and high-pressure (0.9 MPa) environment test. The combination of compression resistance, mechanical flexibility, and excellent thermal insulation provides an appealing material for efficient thermal insulation in extreme environments.