bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Simple, Transition Metal Catalyst‐Free Method for the Design of Complex Organic Building Blocks Used to Construct Porous Metal–Organic Frameworks
Authors: Kochetygov Ilia , Roth Jocelyn , Espín Jordi , Pache Sophia , Justin Anita , Schertenleib Till , Taheri Nazanin , Chernyshov Dmitry , Queen Wendy L. 
Published: February 2023

AbstractThe design of metal–organic frameworks (MOFs) having large pore sizes and volumes often requires the use of complex organic ligands, currently synthesized using costly and time‐consuming palladium‐catalyzed coupling chemistry. Thus, in the present work, a new strategy for ligand design is reported, where piperazine and dihydrophenazine units are used as substitutes for benzene rings, which are the basic building block of most MOF ligands. This chemistry, which is based on simple, nucleophilic aromatic substitution (SNAr) reactions, is used for the transition metal catalyst‐free construction of 21 new, carboxylate‐based ligands with varying sizes, shapes, and denticity and 15 linear di‐ and tetra‐nitriles. Moreover, to demonstrate the utility of the ligands as building blocks, 16 new structurally diverse MOFs having surface areas up to 3100 m2 g−1 were also synthesized.
Hydrated Eutectic Electrolytes Stabilizing Quasi‐Underpotential Mg Plating/Stripping for High‐Voltage Mg Batteries
Authors: Liu Guigui , Tang Yongchao , Li Hongqing , He Jiangfeng , Ye Minghui , Zhang Yufei , Wen Zhipeng , Liu Xiaoqing , Li Cheng Chao 
Published: February 2023

AbstractAqueous rechargeable Mg batteries (ARMBs) usually fail from severe anode passivation, alternatively, executing quasi‐underpotential Mg plating/stripping chemistry (UPMC) on a proper heterogeneous metal substrate is a crucial remedy. Herein, a stable UPMC on Zn substrate is initially achieved in new hydrated eutectic electrolytes (HEEs), delivering an ultralow UPMC overpotential and high energy/voltage plateau of ARMBs. The unique eutectic property remarkably expands the lower limit of electrochemical stability window (ESW) of HEEs and undermines the competition between hydrogen evolution/corrosion reactions and UPMC, enabling a reversible UPMC. The UPMC is carefully revealed by multiple characterizations, which shows a low overpotential of 50 mV at 0.1 mA cm−2 over 550 h. With sulfonic acid‐doped polyaniline (SPANI) cathodes, UPMC‐based full cells show high energy/power densities of 168.6 Wh kg−1/2.1 kWh kg−1 and voltage plateau of 1.3 V, far overwhelming conventional aqueous systems.
Enhanced Four‐Electron Oxygen Reduction Selectivity of Clamp‐Shaped Cobalt(II) Porphyrin(2.1.2.1) Complexes
Authors: Xue Songlin , Ryan Osterloh W. , Lv Xiaojuan , Liu Ningchao , Gao Yimei , Lei Haitao , Fang Yuanyuan , Sun Zhongti , Mei Peifeng , Kuzuhara Daiki , Aratani Naoki , Yamada Hiroko , Cao Rui , Kadish Karl M. , Qiu Fengxian 
Published: February 2023

AbstractThe molecular structure, electrochemistry, spectroelectrochemistry and electrocatalytic oxygen reduction reaction (ORR) features of two CoII porphyrin(2.1.2.1) complexes bearing Ph or F5Ph groups at the two meso‐positions of the macrocycle are examined. Single crystal X‐ray analysis reveal a highly bent, nonplanar macrocyclic conformation of the complex resulting in clamp‐shaped molecular structures. Cyclic voltammetry paired with UV/Vis spectroelectrochemistry in PhCN/0.1 M TBAP suggest that the first electron addition corresponds to a macrocyclic‐centered reduction while spectral changes observed during the first oxidation are consistent with a metal‐centered CoII/CoIII process. The activity of the clamp‐shaped complexes towards heterogeneous ORR in 0.1 M KOH show selectivity towards the 4e− ORR pathway giving H2O. DFT first‐principle calculations on the porphyrin catalyst indicates a lower overpotential for 4e− ORR as compared to the 2e− pathway, consistent with experimental data.
Expanding the Promiscuity of a Copper‐Dependent Oxidase for Enantioselective Cross‐Coupling of Indoles
Authors: Guo Huan , Sun Ningning , Guo Juan , Zhou Tai‐Ping , Tang Langyu , Zhang Wentao , Deng Yaming , Liao Rong‐Zhen , Wu Yuzhou , Wu Guojiao , Zhong Fangrui 
Published: February 2023

AbstractHerein, we disclose the highly enantioselective oxidative cross‐coupling of 3‐hydroxyindole esters with various nucleophilic partners as catalyzed by copper efflux oxidase. The biocatalytic transformation delivers functionalized 2,2‐disubstituted indolin‐3‐ones with excellent optical purity (90–99 % ee), which exhibited anticancer activity against MCF‐7 cell lines, as shown by preliminary biological evaluation. Mechanistic studies and molecular docking results suggest the formation of a phenoxyl radical and enantiocontrol facilitated by a suited enzyme chiral pocket. This study is significant with regard to expanding the catalytic repertoire of natural multicopper oxidases as well as enlarging the synthetic toolbox for sustainable asymmetric oxidative coupling.
High‐Porosity Metal‐Organic Framework Glasses
Authors: Xu Wentao , Hanikel Nikita , Lomachenko Kirill A. , Atzori Cesare , Lund Alicia , Lyu Hao , Zhou Zihui , Angell C. Austen , Yaghi Omar M. 
Published: February 2023

AbstractWe report a synthetic strategy to link titanium‐oxo (Ti‐oxo) clusters into metal‐organic framework (MOF) glasses with high porosity though the carboxylate linkage. A new series of MOF glasses was synthesized by evaporation of solution containing Ti‐oxo clusters Ti16O16(OEt)32, linkers, and m‐cresol. The formation of carboxylate linkages between the Ti‐oxo clusters and the carboxylate linkers was confirmed by Fourier‐transform infrared (FT‐IR) spectroscopy. The structural integrity of the Ti‐oxo clusters within the glasses was evidenced by both X‐ray absorption near edge structure (XANES) and 17O magic‐angle spinning (MAS) NMR. After ligand exchange and activation, the fumarate‐linked MOF glass, termed Ti‐Fum, showed a N2 Brunauer–Emmett–Teller (BET) surface areas of 923 m2 g−1, nearly three times as high as the phenolate‐linked MOF glass with the highest BET surface area prior to this report.
Amorphous NiFe Oxide‐based Nanoreactors for Efficient Electrocatalytic Water Oxidation
Authors: Li Xiaojie , Zhang Huike , Hu Qi , Zhou Weiliang , Shao Jiaxin , Jiang Xingxing , Feng Chao , Yang Hengpan , He Chuanxin 
Published: February 2023

AbstractSynergy engineering is an important way to enhance the kinetic activity of oxygen‐evolution‐reaction (OER) electrocatalysts. Here, we fabricated NiFe amorphous nanoreactor (NiFe‐ANR) oxide as OER electrocatalysts via a mild self‐catalytic reaction. Firstly, the amorphousness helps transform NiFe‐ANR into highly active hydroxyhydroxides, and its many fine‐grain boundaries increase active sites. More importantly, as proved by experiments and finite element analysis, the nanoreactor structure alters the spatial curvature and the mass transfer over the catalyst, thereby enriching OH− in the catalyst surface and inner part. Thus, the catalyst with the structure of amorphous nanoreactors gained excellent activity, far superior to the NiFe catalyst with the structure of crystalline nanoreactor or amorphous non‐nanoreactor. This work provides new insights into the applications and mechanisms of amorphousness and nanoreactors, embodying the “1+1>2” synergy of crystalline state and morphology.
Alternative Fast and Slow Primary Charge‐Separation Pathways in Photosystem II
Authors: Capone Matteo , Sirohiwal Abhishek , Aschi Massimiliano , Pantazis Dimitrios A. , Daidone Isabella 
Published: February 2023

AbstractPhotosystem‐II (PSII) is a multi‐subunit protein complex that harvests sunlight to perform oxygenic photosynthesis. Initial light‐activated charge separation takes place at a reaction centre consisting of four chlorophylls and two pheophytins. Understanding the processes following light excitation remains elusive due to spectral congestion, the ultrafast nature, and multi‐component behaviour of the charge‐separation process. Here, using advanced computational multiscale approaches which take into account the large‐scale configurational flexibility of the system, we identify two possible primary pathways to radical‐pair formation that differ by three orders of magnitude in their kinetics. The fast (short‐range) pathway is dominant, but the existence of an alternative slow (long‐range) charge‐separation pathway hints at the evolution of redundancy that may serve other purposes, adaptive or protective, related to formation of the unique oxidative species that drives water oxidation in PSII.
Pore Aperture Control Toward Size‐Exclusion‐Based Hydrocarbon Separations
Authors: Lal Bhajan , Idrees Karam B. , Xie Haomiao , Smoljan Courtney S. , Shafaie Saman , Islamoglu Timur , Farha Omar K. 
Published: February 2023

AbstractMetal–organic frameworks (MOFs) have been proposed as a promising material for non‐thermal chemical separations owing to their high structural diversity and tunability. Here, we report the synthesis of a zinc‐based MOF containing a three‐dimensional (3D) linker, bicyclo[2.2.2]octane‐1,4‐dicarboxylic acid, with high thermal stability towards the separation of hexane isomers. The incorporation of the 3D linker enhances the structural stability and provides well‐defined pore apertures/channels with sub‐Ångstrom precision. This precision allowed for the separation of similarly sized hexane isomers based on subtle differences in their kinetic diameters. Multi‐component liquid phase batch experiments confirmed the separation of hexanes mixture into linear, monobranched, and dibranched isomers. This work represents a significant milestone in the construction of stable Zn‐based MOFs and the incorporation of 3D linkers as a potential solution to challenging separations.
Alkyds with artistic applications based on drying oils, multifunctional polyalcohols and different polybasic acids
Authors: Bellatin Arciniega Luciano , Meza Yapu Raúl , Obregón Valencia Daniel , Hadzich Antonella , Costa Marcus A. , Ispas Adriana , Bund Andreas , Flores Santiago 
Published: February 2023

AbstractToday's requirements in the art field have challenged researchers to create artistic paintings with attractive appearance and long‐term color stability. Alkyd‐based art mediums have become an important group in the art field, because of their similar characteristics to traditional oils and exceptional drying properties. In this work, high solid alkyd‐based art mediums have been synthesized by the monoglyceride and acidolysis processes. Multifunctional polyols and high unsaturated fatty acid sources were compared and used for alkyd synthesis. The use of a non‐traditional oil of Peruvian origin is proposed. Resins have been characterized according to their physicochemical (acid number, viscosity, color and density) and drying properties. Drying tendencies were verified with the use of quartz crystal microbalance. Also, the behavior of the art mediums mixed with commercial oil paintings and a dry pigment, have also been evaluated. Results indicate that resins containing the polyol with the highest functionality are more viscous and have fewer tendencies to yellowing, while non‐traditional Peruvian oil is the best option for creating light‐colored art mediums. Alkyd mediums prepared by the monoglyceride method gave to oil paintings better characteristics and drying behavior on canvas.
Poly (polyethylene glycol diacrylate‐co‐allyl glycidyl ether) cryogels: Preparation, modification with iminodiacetic acid, and application of Cu(II) removal
Authors: Zhu Zhifei , Li Junying , Ma Feng , Chen Guangxu , Tian Haoran , Li Jian , Yang Pengfei 
Published: February 2023

AbstractIn this study, poly (polyethylene glycol diacrylate‐co‐allyl glycidyl ether) cryogels (p(PEGDA‐co‐AGE)) was synthesized by low‐temperature polymerization using polyethylene glycol diacrylate (PEGDA), allyl glycidyl ether (AGE), and N,N′‐methylenebisacrylamide (MBAAm). The cryogel was then modified with iminodiacetic acid (IDA) by a ring‐opening reaction of AGE to attach carboxyl groups on the surface. The modified cryogel (p(PEGDA‐co‐AGE)‐IDA) was characterized by scanning electron microscope, energy dispersive X‐ray spectra, infrared spectra, X‐ray photoelectron spectroscopy, and compression test, as well as its absorption performance. It was found that the adsorption efficiency and the reusability of cryogels for Cu(II) was related to pH, and the maximum adsorption capacity was 76.49 mg g−1 (pH = 6). In addition, the kinetics of Cu(II) adsorption on cryogels was investigated to clarify the adsorption mechanism.
Influence of accelerators and curing system composition on the cure characteristics, crosslinks structure and properties of acrylonitrile‐butadiene elastomer
Authors: Maciejewska Magdalena , Sowińska‐Baranowska Anna 
Published: February 2023

AbstractThe goal of this work is to study the influence of the type of vulcanization accelerator and the quantitative composition of the curing system on the cure characteristics, morphology of elastomer network, crosslink density and physico‐chemical properties of acrylonitrile‐butadiene rubber (NBR) composites. Sulfur curing systems are investigated, which consist of various types of accelerators, that is, sulfenamide, guanidine and thiuram, applied in various proportions to sulfur. The type of accelerator and the sulfur/accelerator ratio significantly affect both the cure rate and the structure and number of crosslinks resulting from the vulcanization. The highest cure rate and the lowest content of polysulfidic crosslinks are exhibited by rubber composites with efficient (EV) curing systems due to the highest content of accelerators compared to semi‐efficient (SEV) and conventional (CV) systems. The structure of crosslinks strongly affect tensile properties and hardness of the vulcanizates as well as their solvent resistance, thermal stability and resistance to thermo‐oxidative aging.
Red‐emissive Dual‐state Fluorogenic Probe for Wash‐free Imaging of Lipid Droplets in Living Cells and Fatty Liver Tissues
Authors: Wang Hui , Zhang Cuifeng , Hu Lei , Tang Fang , Wang Yaxuan , Ding Feiyang , Lu Jingwen , Ding Aixiang 
Published: February 2023

AbstractLipid droplet (LD) dysfunction can result in various diseases, such as nonalcoholic fatty liver disease. Imaging agents built on dual‐state emission (DSE) molecules that fluoresce in both dilute solutions and the aggregated state are receiving attention as this type of probe could provide bright fluorescence signals at variable concentrations, avoiding false signal readout caused by the concentration fluctuation in living systems. Herein, we identified a red emissive molecule featuring DSE, from three newly synthesized molecules, for specific detection of LDs in live cells. The bioimaging abilities have been well confirmed by optical spectroscopies, theoretical calculations, cell experiments, as well as animal studies. The DSE probe is effective for LD detection at concentrations ranging from 1 μM to 100 μM while retaining high brightness and signal fidelity. This study provides a knowledge base for the future design of DSE‐active fluorescent probes for understanding LD‐related diseases.
Sample size calculation for the combination test under nonproportional hazards
Authors: Cheng Huan , He Jianghua 
Published: February 2023

AbstractFor sample size calculation in clinical trials with survival endpoints, the logrank test, which is the optimal method under the proportional hazard (PH) assumption, is predominantly used. In reality, the PH assumption may not hold. For example, in immuno‐oncology trials, delayed treatment effects are often expected. The sample size without considering the potential violation of the PH assumption may lead to an underpowered study. In recent years, combination tests such as the maximum weighted logrank test have received great attention because of their robust performance in various hazards scenarios. In this paper, we propose a flexible simulation‐free procedure to calculate the sample size using combination tests. The procedure extends the Lakatos' Markov model and allows for complex situations encountered in a clinical trial, like staggered entry, dropouts, etc. We evaluate the procedure using two maximum weighted logrank tests, one projection‐type test, and three other commonly used tests under various hazards scenarios. The simulation studies show that the proposed method can achieve the target power for all compared tests in most scenarios. The combination tests exhibit robust performance under correct specification and misspecification scenarios and are highly recommended when the hazard‐changing patterns are unknown beforehand. Finally, we demonstrate our method using two clinical trial examples and provide suggestions about the sample size calculations under nonproportional hazards.
Reaction intensification for biocatalytic production of polyphenolic natural product di‐C‐β‐glucosides
Authors: Li Tuo , Borg Annika J. E. , Krammer Leo , Breinbauer Rolf , Nidetzky Bernd 
Published: February 2023

AbstractPolyphenolic aglycones featuring two sugars individually attached via C‐glycosidic linkage (di‐C‐glycosides) represent a rare class of plant natural products with unique physicochemical properties and biological activities. Natural scarcity of such di‐C‐glycosides limits their use‐inspired exploration as pharmaceutical ingredients. Here, we show a biocatalytic process technology for reaction‐intensified production of the di‐C‐β‐glucosides of two representative phenol substrates, phloretin (a natural flavonoid) and phenyl‐trihydroxyacetophenone (a phenolic synthon for synthesis), from sucrose. The synthesis proceeds via an iterative two‐fold C‐glycosylation of the respective aglycone, supplied as inclusion complex with 2‐hydroxypropyl β‐cyclodextrin for enhanced water solubility of up to 50 mmol/L, catalyzed by a kumquat di‐C‐glycosyltransferase (di‐CGT), and it uses UDP‐Glc provided in situ from sucrose by a soybean sucrose synthase, with catalytic amounts (≤3 mol%) of UDP added. Time course analysis reveals the second C‐glycosylation as rate‐limiting (0.4–0.5 mmol/L/min) for the di‐C‐glucoside production. With internal supply from sucrose keeping the UDP‐Glc at a constant steady‐state concentration (≥50% of the UDP added) during the reaction, the di‐C‐glycosylation is driven to completion (≥95% yield). Contrary to the mono‐C‐glucoside intermediate which is stable, the di‐C‐glucoside requires the addition of reducing agent (10 mmol/L 2‐mercaptoethanol) to prevent its decomposition during the synthesis. Both di‐C‐glucosides are isolated from the reaction mixtures in excellent purity (≥95%), and their expected structures are confirmed by NMR. Collectively, this study demonstrates efficient glycosyltransferase cascade reaction for flexible use in natural product di‐C‐β‐glucoside synthesis from expedient substrates.
etiBsu1209: A comprehensive multiscale metabolic model for Bacillus subtilis
Authors: Bi Xinyu , Cheng Yang , Xu Xianhao , Lv Xueqin , Liu Yanfeng , Li Jianghua , Du Guocheng , Chen Jian , Ledesma‐Amaro Rodrigo , Liu Long 
Published: February 2023

AbstractGenome‐scale metabolic models (GEMs) have been widely used to guide the computational design of microbial cell factories, and to date, seven GEMs have been reported for Bacillus subtilis, a model gram‐positive microorganism widely used in bioproduction of functional nutraceuticals and food ingredients. However, none of them are widely used because they often lead to erroneous predictions due to their low predictive power and lack of information on regulatory mechanisms. In this work, we constructed a new version of GEM for B. subtilis (iBsu1209), which contains 1209 genes, 1595 metabolites, and 1948 reactions. We applied machine learning to fill gaps, which formed a relatively complete metabolic network able to predict with high accuracy (89.3%) the growth of 1209 mutants under 12 different culture conditions. In addition, we developed a visualization and code‐free software, Model Tool, for multiconstraints model reconstruction and analysis. We used this software to construct etiBsu1209, a multiscale model that integrates enzymatic constraints, thermodynamic constraints, and transcriptional regulatory networks. Furthermore, we used etiBsu1209 to guide a metabolic engineering strategy (knocking out fabI and yfkN genes) for the overproduction of nutraceutical menaquinone‐7, and the titer increased to 153.94 mg/L, 2.2‐times that of the parental strain. To the best of our knowledge, etiBsu1209 is the first comprehensive multiscale model for B. subtilis and can serve as a solid basis for rational computational design of B. subtilis cell factories for bioproduction.
The microRNomes of Chinese hamster ovary (CHO) cells and their extracellular vesicles, and how they respond to osmotic and ammonia stress
Authors: Belliveau Jessica , Papoutsakis Eleftherios T. 
Published: February 2023

AbstractA new area of focus in Chinese hamster ovary (CHO) biotechnology is the role of small (exosomes) and large (microvesicles or microparticles) extracellular vesicles (EVs). CHO cells in culture exchange large quantities of proteins and RNA through these EVs, yet the content and role of these EVs remain elusive. MicroRNAs (miRs or miRNA) are central to adaptive responses to stress and more broadly to changes in culture conditions. Given that EVs are highly enriched in miRs, and that EVs release large quantities of miRs both in vivo and in vitro, EVs and their miR content likely play an important role in adaptive responses. Here we report the miRNA landscape of CHO cells and their EVs under normal culture conditions and under ammonia and osmotic stress. We show that both cells and EVs are highly enriched in five miRs (among over 600 miRs) that make up about half of their total miR content, and that these highly enriched miRs differ significantly between normal and stress culture conditions. Notable is the high enrichment in miR‐92a and miR‐23a under normal culture conditions, in contrast to the high enrichment in let‐7 family miRs (let‐7c, let‐7b, and let‐7a) under both stress conditions. The latter suggests a preserved stress‐responsive function of the let‐7 miR family, one of the most highly preserved miR families across species, where among other functions, let‐7 miRs regulate core oncogenes, which, depending on the biological context, may tip the balance between cell cycle arrest and apoptosis. While the expected—based on their profound enrichment—important role of these highly enriched miRs remains to be dissected, our data and analysis constitute an important resource for exploring the role of miRs in cell adaptation as well as for synthetic applications.
Biomimetic nanotherapeutics for targeted drug delivery to glioblastoma multiforme
Authors: Lim Xin Yuan , Capinpin Sharah Mae , Bolem Nagarjun , Foo Aaron Song Chuan , Yip Wai‐Cheong George , Kumar Alan Prem , Teh Daniel Boon Loong 
Published: February 2023

AbstractGlioblastoma multiforme (GBM) is an aggressive brain tumor with poor prognosis and high mortality, with no curative treatment to date as limited trafficking across the blood–brain barrier (BBB) combined with tumor heterogeneity often leads to therapeutic failure. Although modern medicine poses a wide range of drugs that are otherwise efficacious in treating other tumors, they often do not achieve therapeutic concentrations in the brain, hence driving the need for more effective drug delivery strategies. Nanotechnology, an interdisciplinary field, has been gaining immense popularity in recent years for remarkable advancements such as nanoparticle (NP) drug carriers, which possess extraordinary versatility in modifying surface coatings to home in on target cells, including those beyond the BBB. In this review, we will be highlighting recent developments in biomimetic NPs in GBM therapy and how these allowed us to overcome the physiological and anatomical challenges that have long plagued GBM treatment.