bluuebunny/crossref_metadata_2025_split huggingface dataset:
Universal Design and Efficient Synthesis for High Ambipolar Mobility Emissive Conjugated Polymers
Authors: Zhang Yihan , Xu Chenhui , Wang Pu , Gao Can , Li Wenhao , Ni Zhenjie , Han Yang , Zhao Yan , Geng Yanhou , Wang Zhaohui , Hu Wenping , Dong Huanli 
Published: March 2024

AbstractHigh ambipolar mobility emissive conjugated polymers (HAME‐CPs) are perfect candidates for organic optoelectronic devices, such as polymer light emitting transistors. However, due to intrinsic trade‐off relationship between high ambipolar mobility and strong solid‐state luminescence, the development of HAME‐CPs suffers from high structural and synthetic complexity. Herein, a universal design principle and simple synthetic approach for HAME‐CPs are developed. A series of simple non‐fused polymers composed of charge transfer units, π bridges and emissive units are synthesized via a two‐step microwave assisted C−H arylation and direct arylation polymerization protocol with high total yields up to 61 %. The synthetic protocol is verified valid among 7 monomers and 8 polymers. Most importantly, all 8 conjugated polymers have strong solid‐state emission with high photoluminescence quantum yields up to 24 %. Furthermore, 4 polymers exhibit high ambipolar field effect mobility up to 10−2 cm2 V−1 s−1, and can be used in multifunctional optoelectronic devices. This work opens a new avenue for developing HAME‐CPs by efficient synthesis and rational design.
Turning Non‐Emissive Schiff Bases Into Aggregate Emitters
Authors: Chen Xinmeng , Zhang Siwei , Jiang Yefei , He Guiying , Zhang Minjie , Wang Jin , Deng Zihao , Wang Haoran , Lam Jacky W. Y. , Hu Lianrui , Zhong Tang Ben 
Published: March 2024

AbstractSchiff bases are a crucial component in various functional materials but often exhibit non‐emissive behavior which significantly limits their potential applications as luminescent materials. However, traditional approaches to convert them into aggregate emitters often require intricate molecular design, tedious synthesis, and significant time and resource consumption. Herein, we present a cocrystallization‐induced emission strategy that can transform non‐emissive (hetero)aryl‐substituted Schiff bases into green‐yellow to yellow aggregate emitters via even simple grinding of a mixture of Schiff bases and 1,2,4,5‐tetracyanobenzene (TCB) mixtures. The combined experimental and theoretical analysis revealed that the cocrystallization inhibits the C=N isomerization and promotes face‐to‐face π–π interaction, which restricts access to both the dark state and canonical intersection to ultimately induce emission. Furthermore, the induced emission enables the observation of solid‐state molecular diffusion through fluorescence signals, advancing white light emission diodes, and notably, solution‐processed organic light‐emitting diodes based on cocrystal for the first time. This study not only highlights the potential of developing new C=N structural motifs for AIEgens but also could boost advancements in related structure motifs like C=C and N=N.
Identification of “Structural Pin” Interactions and their Significance for the Conformational Control of Macrocyclic Scaffolds
Authors: Appavoo Solomon D. , Heller Nicholas W. , van Campenhout Christian T. , Saunders George J. , Yudin Andrei K. 
Published: March 2024

AbstractWhile peptide macrocycles with rigidified conformations have proven to be useful in the design of chemical probes of protein targets, conformational flexibility and rapid interconversion can be equally vital for biological activity and favorable physicochemical properties. This study introduces the concept of “structural pin”, which describes a hydrogen bond that is largely responsible for stabilizing the entire macrocycle backbone conformation. Structural analysis of macrocycles using nuclear magnetic resonance (NMR), molecular modelling and X‐ray diffraction indicates that disruption of the structural pin can drastically influence the conformation of the entire ring, resulting in novel states with increased flexibility. This finding provides a new tool to interrogate dynamic behaviour of macrocycles. Identification of structural pins offers a useful conceptual framework to understand positions that can either be modified to give flexible structures or retained to maintain the rigidity of the scaffold.
Bridged Bicyclic Lactam Enables Chemically Recyclable Nylon
Authors: Lv Wenxiu , Li Maosheng , Tao Youhua 
Published: March 2024

AbstractNylon, a widely‐used high‐performance thermoplastic, boasts exceptional durability and resistance to various solvents and weak acids, making it indispensable across diverse applications. However, its nonbiodegradable nature has led to alarming environmental pollution in land and oceans. Chemical recycling to monomers (CRM) stands as a crucial strategy for establishing a circular plastic economy, but the CRM of nylon remains largely unexplored. Herein, we introduce the bridged bicyclic lactam 5‐azabicyclo[2.2.1]octan‐6‐one (5/6‐LM), evolved from δ‐valerolactam and pyrrolidone, to solve the trade‐off in depolymerizability and performance. Notably, 5/6‐LM exhibits nearly 95 % conversion in mild polymerization conditions and efficient depolymerization catalyzed by lewis acids. This compound is synthetically accessible from commercially available chemicals in a single step at room temperature, demonstrating high efficiency and scalability up to 50 g in laboratory. Furthermore, the resulting polyamide displays remarkable attributes including high crystallinity and thermostability up to 283 °C, significantly broadening the scope of chemically recyclable nylons.
Solar‐Light‐Driven Photocatalytic Oxidative Coupling of Phenol Derivatives over Bismuth‐Based Porous Metal Halide Perovskites
Authors: Lee Jinsun , Kumar Ashwani , Tüysüz Harun 
Published: March 2024

AbstractThe selective oxidative coupling of phenol derivatives, involving carbon‐carbon (C−C) and carbon‐oxygen (C−O) bond formation, has emerged as a critical approach in the synthesis of natural products. However, achieving precise control over the selectivity in coupling reactions of unsubstituted phenols utilizing solar light as the driving force remains a big challenge. In this study, we report a series of porous Cs3Bi2X9 (X=Cl, Br, I) photocatalysts with tailored band gaps and compositions engineered for efficient solar‐light‐driven oxidative phenol coupling. Notably, p‐Cs3Bi2Br9 exhibited about 73 % selectivity for C−C coupling, displaying a high formation rate of 47.3 μmol gcat−1 h−1 under solar radiation. Furthermore, this approach enables control of the site‐selectivity for phenol derivatives on Cs3Bi2X9, enhancing C−C coupling. The distinctive porous structure and appropriate band‐edge positions of Cs3Bi2Br9 facilitated efficient charge separation, and surface interaction/activation of phenolic hydroxyl groups, resulting in the kinetically preferred formation of C−C over C−O bond. Mechanistic insights into the reaction pathway, supported by comprehensive control experiments, unveiled the crucial role of interfacial charge transfers and Lewis acid Bi sites in stabilizing phenolic intermediates, thereby directing the regioselectivity of diradical couplings and resulting in the formation of unsymmetrical biphenols.
Microfiltration of milk fat globules for particle size affects key sensory parameters of Cheddar cheese
Authors: Eyres Graham , Gunaratne Thejani , Cochet‐Broch Maeva , Mazzonetto Michael , Singh Tanoj , Logan Amy 
Published: March 2024

AbstractDescriptive sensory analysis discriminated between the appearance, aroma, flavor, taste and texture of Cheddar cheese samples prepared from milk varying in fat globule size; small milk fat globule milk (SMM, d4,3 = 2.76 ± 0.07 μm), large milk fat globule milk (LMM, d4,3 = 5.07 ± 0.06 μm) and Control (d4,3 = 3.91 ± 0.09 μm), over a six‐month maturation period. Significant differences were measured between SMM, LMM and the Control as each cheese matured, where SMM was the most different across all parameters examined. SMM was lowest in color intensity (34.6 < 38.8–47.0), firmness (29.4 < 36.1–47.7), and fracturability (24.5 < 28.8–30.7), and highest in cohesiveness (57.0 > 39.8–45.8), adhesiveness (52.9 > 39.0–45.4), and smoothness (50.4 > 37.9–44.0). Moreover, SMM was more intense than the Control in cultured odor (34.9 > 29.6–30.6) and flavor (45.5 > 34.9–36.2), rancid (23.3 > 16.0–18.6) and metallic (17.7 > 14.3) flavor, salty taste (45.7 > 40.3–40.5) and aftertaste (38.5 > 34.9–35.8), sour (36.3 > 28.9) and umami taste (19.6 > 16.4); attributes that align with the degree of maturation. LMM showed similar differences to the Control, but was firmer (36.1 > 29.4), less cohesive (45.8 < 57.0), adhesive (45.4 < 52.9) and smooth (44.0 < 50.4) and had a less intense cultured odor (31.5 < 34.9) than SMM. An increase in salty taste was associated with a decrease in cheese firmness (−0.91, p < 0.0001). These results could provide process‐driven solutions that allow the dairy industry to decrease maturation time or create differentiated cheese products to meet specific consumer tastes or function.
Compatibility analysis between natural rubber/polybutadiene rubber and protective waxes based on experiments and materials studio simulations
Authors: Jiang Shuangyan , Li Yue , Yong Zhanfu 
Published: March 2024

AbstractProtective waxes are typically mixtures of paraffin and microcrystalline waxes that retard the aging of unsaturated rubbers and are widely used in rubber products. The wax solubility of rubber products is important for understanding the migration behavior and film formation of waxes and determining the appropriate wax content in rubber compounds. In this article, protective waxes were applied to natural rubber (NR)/polybutadiene rubber (BR) based sidewall rubber and the compatibility between NR and BR and the protective wax dissolution in these rubbers were investigated with a focus on the former investigation through Materials Studio simulations. It was found that the simulation results are strongly correlated with the wax migration test results on compounded and cured rubber at different NR/BR mass ratios. Blends and mesoscopic dynamics simulations yielded good compatibility between NR and BR and favorable blend morphology. By analyzing the solubility parameter, R value, mean square displacement and diffusion coefficient of wax chains with different lengths in the NR/BR matrix, the mechanism and reasons for the wax precipitation variation of protective waxes at varying NR/BR mass ratios were analyzed from a microstructural point of view, which provides strong theoretical support for the design of the molecular structure of protective waxes.
Three‐dimensional molar enamel thickness and distribution patterns in Late Miocene Lufengpithecus lufengensis from Shihuiba, Southwest China
Authors: Zhang Lizhao , Du Baopu , Hu Rong , Zhao Lingxia 
Published: March 2024

AbstractEnamel thickness and distribution provide dietary insights in hominoids. Yet, three‐dimensional (3D) enamel analysis of the Late Miocene Lufengpithecus from southwest China is lacking. We digitally reconstructed 68 unworn or lightly worn Lufengpithecus (L.) lufengensis molars using micro‐computed tomography (micro‐CT). Comparisons with modern humans, Homo erectus, extant/fossil Pongo, Pan, and Gorilla reveal L. lufengensis has “intermediate/thick” enamel, thicker than Pongo and Gorilla, but thinner than modern humans and H. erectus. In enamel distribution, relatively thicker enamel lies on the lingual cusps of the maxillary molars. The hypoconid, hypoconulid, and entoconid exhibit relatively thicker enamel compared to the metaconid and protoconid of the mandibular molars. L. lufengensis also exhibits an uneven pattern on the lingual and buccal walls. With relatively intermediate/thick enamel and distinctive distribution pattern, L. lufengensis may be able to respond to dietary variation in seasonal habitats.
Variation of gene expression of fatty acid acyl CoA reductase associated with wax secretion of a scale insect, Ericerus pela, and identification of its regulation factors through the accessible chromatin analyses and yeast one‐hybrid
Authors: Fu Zuoyi , Shi Yuanchong , Yu Shuhui , Zhao Qiuyu , Mo Haifeng , Yang Pu 
Published: March 2024

AbstractThe Chinese white wax scale insect (CWWSI), Ericerus pela, can secret an amount of wax equivalent to their body weight. Previous studies demonstrated the fatty acyl‐CoA reductase (far3) plays a pivotal role in wax secretion of CWWSI. The high expression of far3 is crucial for the massive wax secretion. However, the transcription regulation of far3 was not clear. To identify regulatory factors that control the expression of far3, the assay for transposase‐accessible chromatin (ATAC) and yeast one‐hybrid (Y1H) were carried out in this study. The ATAC sequencing of the CWWSI at the early wax‐secretion stage ATAC‐seq resulted in 22.75 GB raw data, generated 75,827,225 clean reads and revealed 142,771 peaks. There was one significant peak in the 3 kb upstream regulation regions. The peak sequence is located between −1000 and −670 bp upstream of the far3 transcription start site, spanning a length of 331 bp. This peak sequence served as bait for creating the pAbAi‐peak recombinant vector, used in Y1H screenings to identify proteins interacting with far3 gene. The results indicate a successful CWWSI cDNA library construction with a capacity of 1.2 × 107 colony forming unit, a 95.8% recombination rate, and insert sizes between 1,000 and 2,000 bp. Self‐activation tests established that 100 ng/mL of AbA effectively inhibited bait vector self‐activation. Finally, a total of 88 positive clones were selected. After sequencing and removal of duplication, 63 unique clones were obtained from these screened colonies. By aligning the clone sequences with full‐length transcriptome and genome of CWWSI, the full‐length coding sequences of these clones were obtained. BlastX analysis identified a transcription factor, nuclear transcription factor Y beta, and two co‐activators, cAMP‐response‐element‐binding‐protein‐binding protein and WW domain binding protein 2. Reverse transcription quantitative polymerase chain reaction analysis confirmed that their expression patterns were consistent with the developmental stages preceding wax secretion and matched the wax secretion characteristics during ovulation periods. These results are beneficial for further research into the regulatory mechanisms of wax secretion of CWWSI.
Synthesis, biological activities, and molecular docking studies of triazolo[4,3‐b]triazine derivatives as a novel class of α‐glucosidase and α‐amylase inhibitors
Authors: Seyfi Soheila , Salarinejad Somayeh , Moghimi Setareh , Toolabi Mahsa , Sadeghian Nastaran , Tüzün Burak , Firoozpour Loghman , Ketabforoosh Shima H. M. E. , Taslimi Parham , Foroumadi Alireza 
Published: March 2024

AbstractIn diabetes mellitus, amylase and glucosidase enzymes are the primary triggers. The main function of these enzymes is to break macromolecules into simple sugar units, which directly affect blood sugar levels by increasing blood permeability. To overcome this metabolic effect, there is a need for a potent and effective inhibitor capable of suppressing the enzymatic conversion of sugar macromolecules into their smaller units. Herein, we reported the discovery of a series of substituted triazolo[4,3‐b][1,2,4]triazine derivatives as α‐glucosidase and α‐amylase inhibitors. All target compounds demonstrated significant inhibitory activities against α‐glucosidase and α‐amylase enzymes compared with acarbose as the positive control. The most potent compound 10k, 2‐[(6‐phenyl‐[1,2,4]triazolo[4,3‐b][1,2,4]triazin‐3‐yl)thio]‐N‐[4‐(trifluoromethyl)phenyl]acetamide, demonstrated IC50 values of 31.87 and 24.64 nM against α‐glucosidase and α‐amylase enzymes, respectively. To study their mechanism of action, kinetic studies were also done, which determined the mode of inhibition of both enzymes. Molecular docking was used to confirm the binding interactions of the most active compounds.
Screening of Chelidonium majus isoquinoline alkaloids reveals berberine and chelidonine as selective ligands for the nuclear receptors RORβ and HNF4α, respectively
Authors: Salehi Sohrab , Schallmayer Espen , Bandomir Nils , Kärcher Annette , Güth Jan‐Frederik , Heitel Pascal 
Published: March 2024

AbstractThe nuclear receptors hepatocyte nuclear factor 4α (HNF4α) and retinoic acid receptor‐related orphan receptor‐β (RORβ) are ligand‐regulated transcription factors and potential drug targets for metabolic disorders. However, there is a lack of small molecular, selective ligands to explore the therapeutic potential in further detail. Here, we report the discovery of greater celandine (Chelidonium majus) isoquinoline alkaloids as nuclear receptor modulators: Berberine is a selective RORβ inverse agonist and modulated target genes involved in the circadian clock, photoreceptor cell development, and neuronal function. The structurally related chelidonine was identified as a ligand for the constitutively active HNF4α receptor, with nanomolar potency in a cellular reporter gene assay. In human liver cancer cells naturally expressing high levels of HNF4α, chelidonine acted as an inverse agonist and downregulated genes associated with gluconeogenesis and drug metabolism. Both berberine and chelidonine are promising tool compounds to further investigate their target nuclear receptors and for drug discovery.
Health benefits of fraxetin: From chemistry to medicine
Authors: Ha Nguyen Manh , Son Ninh The 
Published: March 2024

AbstractFraxetin is a bioactive molecule present in various natural plants, especially Cortex Fraxini. Evidenced outcomes in phytochemical and biological analyses for this agent are now available in the literature, but an insightful review is yet unknown. The goal of the current research is to offer a panoramic illustration of natural observation, biosynthesis, synthesis, pharmacology, and pharmacokinetics for fraxetin. Esculetin and ferulic acid acted as precursors in the enzymatic biosynthetic route, whereas fraxetin could be easily synthesized from simple phenols. A great deal of interest was obtained in using this molecule for pharmacological targets. Herein, its pharmacological value included anticancer, antioxidative, anti‐inflammatory, antidiabetic, antiobesity, and antimicrobial activities, as well as the protection of the liver, neurons, heart, bone, lung, kidney, and others. Anticancer activity may involve the inhibition of proliferation, invasion, and migration, together with apoptotic induction. Health benefits from this molecule were deduced from its ability to suppress cytokines and protect the immune syndrome. Various signaling pathways, such as Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3), phosphoinositide 3 kinase (PI3K)/protein kinase B (Akt), nuclear factor kappa B (NF‐κB)/NLRP3, Akt/AMPK, have been proposed for in vitro and in vivo mechanisms of action. Fraxetin is highly distributed to rat plasma and several organs. However, more pharmacokinetic studies to improve its bioavailability are needed since its solubility in water is still limited.
Genome‐scale metabolic modeling of Thraustochytrium sp. RT2316‐16: Effects of nutrients on metabolism
Authors: Shene Carolina , Leyton Allison , Flores Liset , Chavez Daniela , Asenjo Juan A. , Chisti Yusuf 
Published: March 2024

AbstractMarine thraustochytrids produce metabolically important lipids such as the long‐chain omega‐3 polyunsaturated fatty acids, carotenoids, and sterols. The growth and lipid production in thraustochytrids depends on the composition of the culture medium that often contains yeast extract as a source of amino acids. This work discusses the effects of individual amino acids provided in the culture medium as the only source of nitrogen, on the production of biomass and lipids by the thraustochytrid Thraustochytrium sp. RT2316‐16. A reconstructed metabolic network based on the annotated genome of RT2316‐16 in combination with flux balance analysis was used to explain the observed growth and consumption of the nutrients. The culture kinetic parameters estimated from the experimental data were used to constrain the flux via the nutrient consumption rates and the specific growth rate of the triacylglycerol‐free biomass in the genome‐scale metabolic model (GEM) to predict the specific rate of ATP production for cell maintenance. A relationship was identified between the specific rate of ATP production for maintenance and the specific rate of glucose consumption. The GEM and the derived relationship for the production of ATP for maintenance were used in linear optimization problems, to successfully predict the specific growth rate of RT2316‐16 in different experimental conditions.
Prediction models for the flux decay profile and initial flux of microfiltration for therapeutic proteins
Authors: Inoue Kota , Masuda Yumiko , Torisu Tetsuo , Nonaka Koichi , Uchiyama Susumu 
Published: March 2024

AbstractMicrofiltration (MF) is an essential step during biopharmaceutical manufacturing. However, unexpected flux decay can occur. Although the flux decay profile and initial flux are important factors determining MF filterability, predicting them accurately is challenging, as the root cause of unexpected flux decay remains elusive. In this study, the methodology for developing a prediction model of flux decay profiles was established. First, the filtration profiles of different monodisperse polystyrene latex and silica beads of various sizes were evaluated. These results revealed that the size and surface electrostatic properties of the beads affect the flux decay profile. Taking the size and surface electrostatic properties of protein aggregates into account, we constructed a predictive model using model bead filtration profiles. We showed that this methodology was applicable to two different MF filters to predict the flux decay profile of therapeutic proteins. Because our proposed prediction model is based on normalized flux, the initial flux is required to predict the overall filtration profile. Then, we applied the Hagen–Poiseuille equation using sample viscosity values to estimate the initial flux. The developed prediction models can be used for effective MF scale‐up assessment during the early stages of process development.
An experimental and modeling approach to describe the deactivation of cellulases at the air–liquid interface
Authors: Cachafeiro Laura , Heiss‐Blanquet Senta , Hudebine Damien 
Published: March 2024

AbstractUnderstanding the reaction mechanisms involved in the enzymatic hydrolysis of cellulose is important because it is kinetically the most limiting step of the bioethanol production process. The present work focuses on the enzymatic deactivation at the air–liquid interface, which is one of the aspects contributing to this global deactivation. This phenomenon has already been experimentally proven, but this is the first time that a model has been proposed to describe it. Experiments were performed by incubating Celluclast cocktail solutions on an orbital stirring system at different enzyme concentrations and different surface‐to‐volume ratios. A 5‐day follow‐up was carried out by measuring the global FPase activity of cellulases for each condition tested. The activity loss was proven to depend on both the air–liquid surface area and the enzyme concentration. Both observations suggest that the loss of activity takes place at the air–liquid surface, the total amount of enzymes varying with volume or enzyme concentration. Furthermore, tests performed using five individual enzymes purified from a Trichoderma reesei cocktail showed that the only cellulase that is deactivated at the air–liquid interface is cellobiohydrolase II. From the experimental data collected by varying the initial enzyme concentration and the ratio surface to volume, it was possible to develop, for the first time, a model that describes the loss of activity at the air‐liquid interface for this configuration.