bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapid tooling for rubber extrusion molding by digital light processing 3D printing with dual curable vitrimers
Authors: Höller Rita , Hrbinič Katja , Reisinger David , Alabiso Walter , Schuschnigg Stephan , Fleisch Mathias , Waly Christoph , Rossegger Elisabeth , Schlögl Sandra
Published: February 2024

For the manufacture of extrusion dies, three‐dimensional (3D) printing with photopolymers offers numerous advantages including flexibility, high surface quality, decent build speed, low costs and a reduced amount of waste. However, the majority of photocurable resins used in vat photopolymerization 3D printing rely on acrylates, which entail 3D‐printed objects with poor mechanical properties. In particular, the high brittleness limits their application in rapid tooling, for which tough materials with high glass transition temperatures (Tg) are required. In the present study, we highlight the use of dual curable acrylate‐epoxy resins with dynamic covalent bonds for the direct fabrication of extrusion dies. During digital light processing (DLP) 3D printing the acrylate network is formed, whose toughness and thermal stability are significantly enhanced by the thermoactivated formation of a second network. By following a postbaking procedure, aminoglycidiyl monomers are cured with an anhydride hardener bearing bulky norbornene groups yielding interpenetrating polymer networks with a Tg > 100°C. The tertiary amine groups present in the structure of the aminoglycidyl derivatives do not only accelerate the ring‐opening reaction but also act as internal catalysts and activate bond exchange reactions between free –OH groups and ester moieties available in the photopolymer. This is confirmed by rheometer studies showing a distinctive stress relaxation at elevated temperature and giving rise to a possible reprocessability of the 3D‐printed dies. With a selected resin formulation, a set of dies is printed by DLP 3D printing, with which a highly filled rubber compound is successfully extruded. The results clearly show that dual curable resins with dynamic covalent bonds are a promising class of material for rapid tooling and pave the way towards a customized and convenient fabrication of extrusion dies for rubber processing.
Effect of Intravenous Zoledronic Acid on Total Knee Replacement in Patients With Symptomatic Knee Osteoarthritis and Without Severe Joint Space Narrowing: A Prespecified Secondary Analysis of a Two‐Year, Multicenter, Double‐Blind, Placebo‐Controlled Clinical Trial
Authors: Cai Guoqi , Laslett Laura L. , Thompson Michael , Cicuttini Flavia , Hill Catherine , Wluka Anita E. , March Lyn , Wang Yuanyuan , Otahal Petr , Stoney James D. , Antony Benny , Buttigieg Kathy , Winzenberg Tania , Jones Graeme , Aitken Dawn
Published: February 2024

Objective

To determine the effect of zoledronic acid (ZA) on the risk of total knee replacement (TKR) in patients with symptomatic knee osteoarthritis and without severe joint space narrowing (JSN).

Methods

We included 222 participants (mean age 62 years, 52% female) from the two‐year Zoledronic Acid for Osteoarthritis Knee Pain trial (113 received 5 mg of ZA annually and 109 received placebo) conducted between November 2013 and October 2017. Primary TKR were identified until February 22, 2022. The effect of ZA on TKR risk was evaluated using Cox proportional hazard regression models. Because the treatment effect failed the proportional hazards assumption, a time‐varying coefficients analysis for treatment was conducted by splitting the study into two periods (ie, within and after two years of randomization).

Results

Over a mean follow‐up of seven years, 39% and 30% of participants had any TKR in the ZA and placebo groups, and 28% and 18% had TKR in the study knee, respectively. Use of ZA was associated with a higher risk of TKR in any knee (hazard ratio [HR] 4.2, 95% confidence interval [CI] 1.2–14.7) and showed a trend in the study knee (HR 6.8, 95%CI 0.9–53.9) during the trial. In the posttrial period, the risk of TKR was similar in the ZA and the placebo groups for any knee (HR 1.2, 95%CI 0.5–1.8) and the study knee (HR 1.4, 95%CI 0.5–2.2).

Conclusion

These results suggest that ZA is not protective against TKR in patients with symptomatic knee osteoarthritis and without severe JSN.

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Intra‐Articular Mineralization on Computerized Tomography of the Knee and Risk of Cartilage Damage: The Multicenter Osteoarthritis Study
Authors: Liew Jean W. , Jarraya Mohammed , Guermazi Ali , Lynch John , Felson David , Nevitt Michael , Lewis Cora E. , Torner James , Roemer Frank W. , Crema Michel D. , Wang Na , Becce Fabio , Rabasa Gabriela , Pascart Tristan , Neogi Tuhina
Published: February 2024

Objective

Intra‐articular (IA) mineralization may contribute to osteoarthritis (OA) structural progression. We studied the association of IA mineralization on knee computed tomography (CT) with cartilage damage worsening on knee magnetic resonance imaging (MRI), with a focus on location‐ and tissue‐specific effects.

Methods

Participants from the Multicenter Osteoarthritis Study with knee CT and MRI scans were included. Presence of IA mineralization on CT was defined as a Boston University Calcium Knee Score >0 anywhere in the knee. Cartilage worsening on MRI was defined as any increase in the MRI OA Knee Score, including incident damage. We evaluated the association of whole‐knee, compartment‐specific (ie, medial or lateral), and subregion‐specific (ie, location‐matched) IA mineralization at baseline with cartilage worsening at two years’ follow‐up in the corresponding locations using binomial regression with generalized estimating equations, adjusting for age, sex, and body mass index (BMI).

Results

We included 1,673 participants (mean age 60 years, 56% female, mean BMI 29). Nine percent had any IA mineralization in the knee, and 47.4% had any cartilage worsening on follow‐up. Mineralization of any tissue in the knee, regardless of location, was not associated with MRI cartilage worsening. However, cartilage mineralization was associated with 1.39 (95% confidence interval 1.04–1.88) times higher risk of cartilage worsening in the same compartment, with similar results in subregion‐specific analysis.

Conclusion

CT‐detected IA mineralization in the cartilage was associated with higher risk of MRI cartilage worsening in the same compartment and subregion over two years. These findings suggest potential localized, tissue‐specific effects of IA mineralization on cartilage pathology in knee OA.
A Data‐Driven Method based on Discrete Wavelet Transform for online Li‐Ion Battery State‐of‐Health Prediction and Monitoring
Authors: Pelosi Dario , Gallorini Federico , Ottaviano Panfilo Andrea , Barelli Linda
Published: February 2024

Transportation electrification is accelerating the clean energy transition. Due to high efficiencies and energy density, Li‐ion batteries (LIBs) are used as on‐board energy carrier for battery electric vehicles (BEVs). LIBs are subject to rapid degradation due to fast‐charging, mechanical, electrical and thermal factors. Thus, state‐of‐health (SoH) prediction is required to optimize LIBs exploitation over their lifespan. An online accurate and easy‐of‐implementation battery SoH prediction and monitoring method for BEV applications is here presented. The method implements discrete wavelet transform (DWT) analysis to voltage profiles, measured while driving. Specifically, an extensive cycle aging experimental campaign on NCR 18650 cells was performed, applying two typical US test drives (urban and extra‐urban drive cycle, respectively) to the cells at different SoH. Moreover, tests carried out on LIBs at different temperatures demonstrated that temperature effect on the implemented DWT‐based method can be distinguished and separated from cycle aging effect. The proposed method allows a real‐time SoH estimation showing a good accuracy (MAE, ME and RMSE respectively result in 0.917, 2.897 and 1.32) without requiring high computational efforts. This allows to assess battery SoH during the driving. The method can also be extended to other chemistries requiring a dedicated experimental activity for the parameters tuning.
Effects of 3.5‐GHz radiofrequency radiation on energy‐regulatory hormone levels in the blood and adipose tissue
Authors: Bektas Hava , Dasdag Suleyman , Altindag Fikret , Akdag Mehmet Z. , Yegin Korkut , Algul Sermin
Published: February 2024

In recent years exposure of living beings to radiofrequency radiation (RFR) emitted from wireless equipment has increased. In this study, we investigated the effects of 3.5‐GHz RFR on hormones that regulate energy metabolism in the body. Twenty‐eight rats were divided into four groups: healthy sham (n = 7), healthy RFR (n = 7), diabetic sham (n = 7), and diabetic RFR (n = 7). Over a month, each group spent 2 h/day in a Plexiglas carousel. The rats in the experimental group were exposed to RFR, but the sham groups were not. At the end of the experiment, blood and adipose tissues were collected from euthanized rats. Total antioxidant, total oxidant, hydrogen peroxide, ghrelin, nesfatin‐1, and irisin were determined. Insulin expression in pancreatic tissues was examined by immunohistochemical analysis. Whole body specific absorption rate was 37 mW/kg. For the parameters analyzed in blood and fat, the estimated effect size varied within the ranges of 0.215–0.929 and 0.503–0.839, respectively. The blood and adipose nesfatin‐1 (p = 0.002), blood and pancreatic insulin are decreased, (p = 0.001), gherelin (p = 0.020), irisin (p = 0.020), and blood glucose (p = 0.040) are increased in healthy and diabetic rats exposed to RFR. While nesfatin‐1 are negatively correlated with oxidative stress, hyperglycemia and insulin, ghrelin and irisin are positively correlated with oxidative stress and hyperglycemia. Thus, RFR may have deleterious effects on energy metabolism, particularly in the presence of diabetes.
Preparation of chromium complexes for ethylene tetramerization catalyst
Authors: Park Jun Hyeong , Park Ju Yong , Baek Jun Won , Seo Yeong Hyun , Lee Mi Ryu , Lee Junseong , Lee Bun Yeoul
Published: February 2024

One of the remaining challenges in the commercialization of a highly efficient ethylene tetramerization catalyst, [1‐CrCl2][B(C6F5)4] (1=iPrN[P(C6H4Si(Octyl)3)2]2), is the generation of small amounts of polyethylene (PE). To address this issue, we explored different activator options and found that (Octyl)3Al was the most effective choice. Building on the observation that [iPrN(PPh2)2]CrCl3(THF) was not completely alkylated by the action of excess Me3Al to form ([iPrN(PPh2)2]Cr(μ2‐Cl)(ClMe2AlClAlMe3))2, we synthesized [ortho‐(MeO)C6H4CH2‐η1C:κO]3Cr, developing a catalytic system comprising this precursor, PNP ligand 1, and [MeN(H)(C18H37)2][B(C6F5)4]. However, this catalytic system exhibited a long induction time (~30 min) and generated a significant amount of PE. Returning to the catalytic system of [1‐CrCl2][B(C6F5)4], we successfully achieved the conversion of [(EtOH)4CrCl2][B(C6F5)4] to [(CH3CN)4CrCl2][B(C6F5)4] at a large scale by designing a specialized glass apparatus. Finally, we discovered that the generation of PE could be reduced by adjusting the reaction conditions during the synthesis of [1‐CrCl2][B(C6F5)4].
An FPGA‐based tool for supporting the design, modeling, and evaluation of hybrid object recognition systems on computer engineering courses
Authors: Guzmán‐Ramírez Enrique , Garcia Ivan , Pacheco Carla , Guerrero‐Ramírez Esteban
Published: February 2024

The field of computer vision is characterized by computationally intensive algorithms and techniques with strict real‐time requirements. Field programmable gate arrays (FPGAs) are based on a concurrent paradigm which allows the design of efficient hardware architectures and has positioned FPGAs as an ideal device for implementing compute‐intensive applications. For this reason, FPGA technology has had a great impact in areas such as computer vision, where one of the main objectives for researchers working in this field is to create efficient automatic object recognition systems. Therefore, the need to provide undergraduates with the necessary skills to design FPGA‐based object recognition systems is evident. With this aim in mind, it is essential that specialization courses related to the design of these systems include the required resources for the student to apply the theoretical knowledge in solving practical problems. In this article, we present a development tool designed to help students, teachers, and researchers during the design‐modeling‐implementation process of object recognition systems based on FPGAs. The proposed tool operates under a modular approach as this facilitates the working on any of the phases of a recognition system and it is considered as a hybrid because the other phases can be developed using a software language. An empirical evaluation involving undergraduates enrolled in a Computer Engineering program was conducted to create a hardware architecture for the DAISY descriptor that uses the homogeneous features of objects immersed in images to produce an efficient representation. By considering similar descriptors such as Scale‐Invariant Feature Transform (SIFT) and Histogram of Oriented Gradients (HOG), DAISY is computed by convolving orientation maps instead of using weighted sums of gradient norms, which offers the same kind of invariance at a lower computational cost for the dense case. The results obtained during such an evaluation indicated that students consider this FPGA‐based tool to be an alternative to receiving practical training on designing systems for solving problems related to the area of object recognition.
Chemical Composition, Toxicity, and Repellency of Essential Oils from Three Hedychium Species Against Stored‐Product Insects
Authors: Wang Jia‐Zhu , Du Yue‐Shen , Qi Yuan‐Tong , Zhang Chen , Zhang Zhao‐Rui , Zhang Hai‐Ming , Du Shu‐Shan
Published: February 2024

Stored products are constantly infested by insects, so finding eco‐friendly bioinsecticides for insect management is important. The work aimed to assess the insecticidal and repellent activity of essential oil (EO) from Hedychium glabrum S. Q. Tong, Hedychium coronarium Koen., and Hedychium yunnanense Gagnep. against Tribolium castaneum, Lasioderma serricorne, and Liposcelis bostrychophila. Results showed that 88 chemical components were identified in the extracted Hedychium EOs, indicating that they exhibited diversity in components. According to principal component analysis (PCA), the composition of the EO from the H. yunnanense stem and leaf (EOHYSL) was significantly different from other EOs due to the different organs and species. The biological activity also varied continuously with plant species and organs. Only the EO of H. yunnanense (EOHY) showed strong fumigant toxicity. While in the contact tests, EOHGR showed the strongest toxicity effect on L. bostrychophila, with a LC50 value of 71.76 μg/cm2, which was closest to the positive control (Pyrethrin). All EOs had remarkable repellent activities against the three target insects, and repellency increased with concentration. According to the results of the comprehensive score, EOHY had the highest potential, which ranged from 0.7999 to 0.8689. Thus, Hedychium EOs possess potential biorational traits to be biological insecticides.
Synergistic Antibacterial Activity of Gallic Acid Based Chalcone Indl 2 by Inhibiting Efflux Pump Transporters
Authors: Dwivedi Gaurav Raj , Pathak Nandini , Tiwari Nimisha , Negi Arvind Singh , Kumar Akhil , Pal Anirban , Sharma Ashok , Darokar Mahendra P.
Published: February 2024

As a part of novel discovery of drugs from natural resources, present study was undertaken to explore the antibacterial potential of chalcone Indl‐2 in combination with different group of antibiotics. MIC of antibiotics was reduced up to eight folds against the different cultures of E. coli by both chalcones. Among the two compounds, the i. e. 1‐(3′, 4,′5′‐trimethoxyphenyl)‐3‐(3‐Indyl)‐prop‐2‐enone (6, Indl‐2), a chalcone derivative of gallic acid (Indl‐2) was better along with tetracycline (TET) worked synergistically and was found to inhibit efflux transporters as obvious by ethidium bromide efflux confirmed by ATPase assays and docking studies. In combination, Indl‐2 kills the MDREC−KG4 cells, post‐antibiotic effect (PAE) of TET was prolonged and mutant prevention concentration (MPC) of TET was also decreased. In‐vivo studies revealed that Indl‐2 reduces the concentration of TNF‐α. In acute oral toxicity study, Indl‐2 was non‐toxic and well tolerated up‐to dose of 2000 mg/kg. Perhaps, the study is going to report gallic acid derived chalcone as synergistic agent acting via inhibiting the primary efflux pumps.
Chemical Composition, Antioxidant, and Antibacterial Activity of Ruta chalepensis L. Ethanolic Extract
Authors: Althaher Arwa R. , Oran Sawsan A. , Awadallah Mirna W. , Ameen Hanan H. , Shehabi Reham F. , Bourghli Laurance M. S. , Mastinu Andrea
Published: February 2024

Ruta chalepensis L. is a versatile herb used in culinary arts and traditional medicine. The study aimed to determine the chemical composition of an ethanolic extract from R. chalepensis and the total phenolic and flavonoid content. Additionally, the extracts′ antimicrobial and antioxidant activities were tested. The disc diffusion method and minimum inhibitory concentration (MIC) were used to test the antibacterial properties on four types of bacteria: Escherichia coli, Proteus penneri, Bacillus cereus, and Staphylococcus aureus. A colorimetric assay was used to evaluate the total phenolic and flavonoid content, and the DPPH method was used to assess the antioxidant activity. The phytochemical constituents were determined using LC–MS/MS. The results indicated that R. chalepensis ethanolic extract had 34 compounds, and the predominant compounds were quercetin (9.2 %), myricetin (8.8 %), and camphene (8.0 %). Moreover, the extract had a good level of polyphenols and flavonoids, as demonstrated by inhibiting free radicals (DPPH) (IC50 was 41.2±0.1). Also, the extract exhibited robust antimicrobial activity against P. penneri and S. aureus with an MIC of 12.5 and 25.0 μg/mL, respectively. In conclusion, the results suggest that the R. chalepensis ethanolic extract has good antioxidant and antibacterial properties that could be utilized to develop new antibacterial agents.
Unlocking the Mysteries of Technical Catalyst Deactivation: A View from Space
Authors: Sharma Shweta , Maurer Florian , Lott Patrick , Sheppard Thomas L.
Published: February 2024

Modern analytical techniques enable researchers to study heterogeneous catalytic systems at extended length scales and with local probing methods which were previously impractical. Such spatially–resolved analyses are ideal for exploring the complex dynamics governing catalytic activity, and more specifically, deactivation. Here we highlight significant experimental concepts and milestones in the spatially–resolved analysis of technical catalysts, where it is now possible to study catalyst behavior even up to industrially relevant scale. At such extended length scales and in contrast to many model systems, spatial heterogeneities in solid catalyst bodies may play a crucial role in controlling catalytic properties and may be closely linked to catalyst deactivation. Spatially–resolved studies can therefore provide a unique source of information about such local phenomena. Researchers can gain a deeper insight into the operational life of a catalyst by understanding deactivation patterns, which are one of many factors influencing the dynamics of catalytic reactions. In turn, this information promotes the design of more robust and sustainable catalytic systems. We therefore outline the current state of spatially–resolved characterization, together with its role in deconvoluting the complexity of technical catalysts and their deactivation.
Dynamics and Coordination of a P2N2 Ligand – from Twisted Conformation to Chelation
Authors: Elvers Benedict J. , Fischer Christian , Schulzke Carola
Published: February 2024

Based on their general spacial flexibility, their Lewis and Brønsted basicity, and ability to mimic second sphere effects the 1,5‐diaza‐3,7‐diphosphacyclooctane ligand family and their complexes have regained substantial scientific interest. It was now possible to structurally analyze a recently reported member of this family with p‐tolyl and t‐butyl substituents on P and N, respectively, (P2p‐tolN2tBu). Notably, the ligand crystallizes with a ‘twisted’ backbone. This compound is the very first of its kind to have been unambiguously characterized with regard to its chemical and molecular structure as being in this conformation. A temperature‐dependent NMR study provides insight into the molecular dynamics of two isomers in solution, which are most likely also both twisted, as judged by the observed limited reactivity. Despite the in principle unfavorable conformation of the free ligand, it was successfully chelated to tungsten and molybdenum centers in mononuclear carbonyl complexes. The ligand, a derivative thereof and four new complexes were comprehensively characterized and analyzed in comparison. This includes single crystal XRD molecular structures of P2p‐tolN2tBu and all four complexes. P2p‐tolN2tBu, regardless of its twisted conformation, is able to coordinate to metal centers given that enough energy (heat) for a conformational change is provided.
C3‐Symmetric Luminescent Diketone with Amido‐Linkage as a Polymorphic Fluorescence Emitter
Authors: Katsumi Shiho , Kugai Yusuke , Louis Marine , Morimoto Tsumoru , Yamada Mihoko , Maisonneuve Stéphane , Goto Chigusa , Métivier Rémi , Kawai Tsuyoshi , Allain Clémence
Published: February 2024

The study introduces a novel C3‐symmetric β‐diketone compound, BTA‐D3, and its monomeric counterpart, D, with a focus on their synthetic procedure, photophysical properties and aggregation behavior. Both compounds exhibit characteristic absorption and weak fluorescence in solution, with BTA‐D3 displaying higher absorption coefficients due to its larger number of diketone units. Density Functional Theory (DFT) calculations suggest increased co‐planarity of diketone groups in BTA‐D3. A significant finding is the Aggregation‐Induced Emission (AIE) property of BTA‐D3, as its fluorescence intensity increases dramatically when exposed to specific solvent ratios. The AIE behavior is attributed to intermolecular excitonic interaction between BTA‐D3 molecules in self‐organized aggregates. We also studied fluorescence anisotropy of BTA‐D3 and D. Despite its larger size, BTA‐D3 showed reduced anisotropy values because of efficient intramolecular energy migration among three diketone units. Furthermore, BTA‐D3 demonstrates unique polymorphism, yielding different emission colors and structures depending on the solvent used. A unique approach is presented for promoting the growth of self‐organized aggregate structures via solvent evaporation, leading to distinct fluorescence properties. This research contributes to the understanding of C3‐symmetric structural molecules and provides insights into strategies for controlling molecular alignment to achieve diverse fluorescence coloration in molecular materials.
Synthesis and Structure of the Small Superelectrophile [C2(OH)2Me2]2+
Authors: Virmani Alan , Jessen Christoph , Kornath Andreas J.
Published: February 2024

The acid‐activation of 1,2‐dicarbonyl compounds plays a key role in a variety of electrophilic reactions, some of which are only accessible in superacidic media when a superelectrophilic dication is formed. To obtain structural and electronic information about these elusive species, the vicinal dication [C2(OH)2Me2]2+ is synthesized and characterized by Raman spectroscopy and X‐ray diffraction. Since this superelectrophile could not be stabilized in convenient superacids, the usage of liquid SO2 turned out to be crucial. The experimental data are discussed together with quantum‐chemical calculations on the B3LYP/aug‐cc‐pVTZ level of theory. Natural Bond Orbital (NBO) analyses quantify the superelectrophilic interactions found in the solid state.
Cationic Hypervalent Chalcogen Bond Catalysis on the Povarov Reaction: Reactivity and Stereoselectivity
Authors: Zhao Chang , Li Ying , Wang Yanjiang , Zeng Yanli
Published: February 2024

Chalcogen bond catalysis, particularly cationic hypervalent chalcogen bond catalysis, is considered to be an effective strategy for organocatalysis. In this work, the cationic hypervalent chalcogen bond catalysis for the Povarov reaction between N‐benzylideneaniline and ethyl vinyl ether was investigated by density functional theory (DFT). The catalytic reaction involves the cycloaddition process and the proton transfer process, and the rate‐determining step is the cycloaddition process. Cationic hypervalent tellurium derivatives bearing CF3 and F groups exhibit superior catalytic activity. For the rate‐determining step, the Gibbs free energy barrier decreases as the positive electrostatic potential of the chalcogen bond catalysts increases. More importantly, the Gibbs free energy barrier has a strong linear correlation with the electrostatic energy of the chalcogen bond in the catalyst‐substrate complex. Furthermore, the catalytic reactions include the endo pathway and exo pathway. The C−H⋅⋅⋅π interaction between the substituent of the ethyl vinyl ether and the aryl ring of the N‐benzylideneaniline contributes to the endo‐selectivity of the reaction. This research contributes to a deeper understanding of chalcogen bond catalysis, providing insights for designing chalcogen bond catalysts with high performance.
Hydrated Formic Acid Clusters and their Interaction with Electrons
Authors: Li Kevin , Ďurana Jozef , Kocábková Barbora , Pysanenko Andrij , Yan Yihui , Ončák Milan , Fárník Michal , Lengyel Jozef
Published: February 2024

We investigate ion formation in hydrated formic acid (FA) clusters upon collision with electrons of variable energy, focusing on electron ionization at 70 eV (EI) and low‐energy (1.5–15 eV) electron attachment (EA). To uncover details about the composition of neutral clusters, we aim to elucidate the ion formation processes in FAM ⋅ WN clusters initiated by interaction with electrons and determine the extent of cluster fragmentation. EI predominantly produces protonated [FAm+H]+ ions, and in FA‐rich clusters, the stable ring structures surrounding H3O+ ions are formed. In contrast, EA leads to a competition between the formation of intact [FAm ⋅ Wn]− and dissociated [FAm ⋅ Wn−H]− fragment ions, influenced by the cluster size, level of hydration, and electron energy. Our findings reveal a predisposition of low‐energy EA towards forming [FAm ⋅ Wn]−, while higher electron energies tend to favor the formation of [FAm ⋅ Wn−H]− due to intracluster ion‐molecule reactions. The comparison of positive and negative ion spectra suggests that the mass spectra of FA‐rich clusters may indicate their actual size and composition. On the other hand, the more weakly bound water evaporation from the clusters depends strongly on the ionization. Thus, for the hydrated clusters, the neutral cluster size can hardly be estimated from the mass spectra.
Selective direct oxidation of 1‐butanol into acetal using hydrogen peroxide and Cs5MPW11(H2O)O39 (M=Fe, Co, Cu) catalysts
Authors: Lachquer Farah , Oulmekki Abdallah , Toyir Jamil
Published: February 2024

Direct catalytic oxidation of alcohols to acetals in one step process is very attractive, because the two steps process leads firstly to aldehydes, which are unstable species serving as reactive intermediates to generate several by‐products reducing process efficiency and selectivity. In this work, a new selective catalytic acetalization of 1‐butanol into 1‐1‐dibutoxybutane acetal using H2O2 in one step process is investigated using Keggin‐type polyoxometalates catalysts. The materials developed consisted of new lacunary phophotungstate salts Cs5MPW11(H2O)O39 (M=Fe, Co and Cu) which were prepared by inorganic solution condensation method and characterized using XRD, IR, SEM and EDX analysis to verify their structure, surface morphology and chemical composition. Cs5CuPW11(H2O)O39 catalyst allowed the highest performance for the oxidation of 1‐butanol at 60 °C using H2O2 excess with a yield approaching 92 % and a turnover number of 784. Such activity is related to a bifunctional behavior of the catalyst as superacid and redox operating system and the synergistic effect created between the [PW11O39]7− Keggin framework, Cs+ and Cu2+.
Pharmacokinetics, Pharmacodynamics, and Safety of Edoxaban in Pediatric Subjects: A Phase I Single‐Dose Study
Authors: Zou Peng , Zahir Hamim , Duggal Anil , Pandya Grishma , Jin James , Leil Tarek A.
Published: February 2024

This was an open‐label, single‐dose, phase I study to characterize the pharmacokinetics (PKs), pharmacodynamics (PDs), and safety of edoxaban in pediatric subjects from birth to 18 years at risk for venous thromboembolism (VTE). Children requiring anticoagulant therapy were enrolled into 5 age cohorts (0 to < 6 months (N = 12), 0.5 to < 2 years (N = 13), 2 to < 6 years (N = 13), 6 to < 12 years (N = 13), and 12 to < 18 years (N = 15)) receiving tablet or oral suspension of edoxaban at doses expected to be equivalent to 30 or 60 mg once daily (q.d.) in adult subjects with VTE. Sixty‐six pediatric subjects were enrolled and completed the study. Edoxaban plasma concentration peaked between 1 and 3 hours and declined rapidly until 4–8 hours. The range of mean total apparent clearance across 5 age cohorts at low and high doses was 0.47 to 1.11 L/h/kg. The ranges of mean volume of central compartment and apparent peripheral volume were 2.31 to 3.59 L/kg and 1.92 to 4.14 L/kg, respectively. Across all age groups, the estimated median exposures were within the 0.5‐ to 1.5‐fold of the median area under the plasma drug concentration‐time curve (AUC) in adult subjects receiving corresponding doses (30 mg q.d. for low dose and 60 mg q.d. for high dose). In all age groups, PD parameters (prothrombin time, activated partial thromboplastin time, and anti‐Factor Xa activity) showed a linear PK‐PD relationship and were in line with previous adult data. The results support further evaluation of the pediatric doses in larger pivotal trials.
A Mouse Model for Eosinophilic Esophagitis (EoE)
Authors: Dsilva Anish , Avlas Shmulik , Rhone Natalie , Itan Michal , Munitz Ariel
Published: February 2024

Eosinophilic esophagitis (EoE) is an emerging chronic T helper type 2 (Th2)‐associated, allergic, and immune‐mediated disease, characterized histologically by eosinophil‐predominant mucosal inflammation and clinically by esophageal dysfunction. Over the past years, the prevalence of EoE has dramatically increased globally. Until recently, most studies of EoE focused on using human biopsies, which are also used for diagnostic purposes, or esophageal epithelial cell lines, which led to major advances in the understanding of EoE. Despite this, a robust mouse model that mimics human disease is still crucial for both understanding disease pathogenesis and as a preclinical model for testing future therapeutics. Herein, we describe a highly reproducible and robust model of EoE that can be performed using wild‐type mice by ear sensitization with oxazolone (OXA) followed by intraesophageal challenges. Experimental EoE elicited by OXA mimics the main histopathological features of human EoE, including intraepithelial eosinophilia, epithelial and lamina propria thickening, basal cell hyperplasia, and fibrosis. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC.

Basic Protocol: Induction of EoE in mice using oxazolone

Support Protocol 1: Preparing the mouse esophagus for histological analysis

Support Protocol 2: Assessment of epithelial and lamina propria thickness using H&E staining

Support Protocol 3: Assessment of eosinophilic infiltration using anti‐MBP and basal cell proliferation using anti‐Ki‐67 staining

Support Protocol 4: Flow cytometry of mouse esophageal samples

Support Protocol 5: ELISA on protein lysates of esophageal samples
Covalent Organic Frameworks for Water Harvesting from Air
Authors: Wen Fuxiang , Huang Ning
Published: February 2024

Despite approximately 70 % of the earth being covered by water, water shortage has emerged as an urgent social challenge. Sorbent‐based atmospheric water harvesting stands out as a potent approach to alleviate the situation, particularly in arid regions. This method requires adsorbents with ample working capacity, rapid kinetics, low energy costs, and long‐term stability under operating conditions. Covalent organic frameworks (COFs) are a novel class of crystalline porous materials and offer distinct advantages due to their high specific surface area, structural diversity, and robustness. These properties enable the rational design and customization of their water‐harvesting capabilities. Herein, the basic concepts about the water sorption process within COFs, including the parameters that qualitatively or quantitatively describe their water isotherms and the mechanism are summarized. Then, the recent methods used to prepare COFs‐based water harvesters are reviewed, emphasizing the structural diversity of COFs and presenting the common empirical understandings of these endeavors. Finally, challenges and research concepts are proposed to help develop next‐generation COFs‐based water harvesters.
Half‐bridge secondary series resonant converter control for full voltage range
Authors: Kong Jiayi , Sun Rui , Xu Mingjin , Liu Xiaoqing
Published: February 2024

This paper proposes a full‐range regulation method for half‐bridge secondary series resonant converter. With the proposed method, the resonant converter can achieve full‐range regulation within a narrow frequency range regardless of the load level. Besides, the converter can be used for the battery charger systems and programmable power supply systems. The primary‐side transistors and the secondary‐side diodes are zero‐voltage switching turned on and zero‐current switching turned off, respectively. In‐depth analysis reveals the characteristics, that is, operation principle, voltage conversion ratio, component stresses, and ZVS condition of the half‐bridge secondary series resonant converter with the proposed method. Besides, the performance comparisons among the different methods are conducted to present the merits of the proposed method. Further, the performance comparisons between the half‐bridge secondary series resonant converter and primary series resonant converter with the proposed method are executed to show their superiority with different turns ratio range of the transformer, respectively. When the turns ratio is larger than 0.5 and smaller than 1, the performance of the half‐bridge primary series resonant converter is better; when the turns ratio is equal to 1, the two configurations feature the same performance; while when the turns ratio is larger than 1, the half‐bridge secondary series resonant converter is preferable. The experimental results validate the theoretical analysis.
Identifying squalene epoxidase as a metabolic vulnerability in high‐risk osteosarcoma using an artificial intelligence‐derived prognostic index
Authors: Wang Yongjie , Ma Xiaolong , Xu Enjie , Huang Zhen , Yang Chen , Zhu Kunpeng , Dong Yang , Zhang Chunlin
Published: February 2024

Background

Osteosarcoma (OSA) presents a clinical challenge and has a low 5‐year survival rate. Currently, the lack of advanced stratification models makes personalized therapy difficult. This study aims to identify novel biomarkers to stratify high‐risk OSA patients and guide treatment.

Methods

We combined 10 machine‐learning algorithms into 101 combinations, from which the optimal model was established for predicting overall survival based on transcriptomic profiles for 254 samples. Alterations in transcriptomic, genomic and epigenomic landscapes were assessed to elucidate mechanisms driving poor prognosis. Single‐cell RNA sequencing (scRNA‐seq) unveiled genes overexpressed in OSA cells as potential therapeutic targets, one of which was validated via tissue staining, knockdown and pharmacological inhibition. We characterized changes in multiple phenotypes, including proliferation, colony formation, migration, invasion, apoptosis, chemosensitivity and in vivo tumourigenicity. RNA‐seq and Western blotting elucidated the impact of squalene epoxidase (SQLE) suppression on signalling pathways.

Results

The artificial intelligence‐derived prognostic index (AIDPI), generated by our model, was an independent prognostic biomarker, outperforming clinicopathological factors and previously published signatures. Incorporating the AIDPI with clinical factors into a nomogram improved predictive accuracy. For user convenience, both the model and nomogram are accessible online. Patients in the high‐AIDPI group exhibited chemoresistance, coupled with overexpression of MYC and SQLE, increased mTORC1 signalling, disrupted PI3K–Akt signalling, and diminished immune infiltration. ScRNA‐seq revealed high expression of MYC and SQLE in OSA cells. Elevated SQLE expression correlated with chemoresistance and worse outcomes in OSA patients. Therapeutically, silencing SQLE suppressed OSA malignancy and enhanced chemosensitivity, mediated by cholesterol depletion and suppression of the FAK/PI3K/Akt/mTOR pathway. Furthermore, the SQLE‐specific inhibitor FR194738 demonstrated anti‐OSA effects in vivo and exhibited synergistic effects with chemotherapeutic agents.

Conclusions

AIDPI is a robust biomarker for identifying the high‐risk subset of OSA patients. The SQLE protein emerges as a metabolic vulnerability in these patients, providing a target with translational potential.
Linking optical data and nitrates in the Lower Mississippi River to enable satellite‐based monitoring of nutrient reduction goals
Authors: Tufillaro Nicholas , Piazza Bryan P. , Reddy Sheila , Baustian Joseph , Sousa Dan , Grötsch Philipp , Lalović Ivan , De Moitié Sara , Zurita Omar
Published: February 2024

Hypoxic zones and associated nitrate pollution from farms, cities and industrial facilities is driving declines in water quality that affect ecosystems, economies and human health in major rivers and coastal areas worldwide. In the Mississippi River, the United States Environmental Protection Agency set a goal of reducing nitrogen loading 20% by 2025, but estimating progress towards this goal is difficult because data from in‐stream gauges and laboratory samples are too sparse. Satellites have the potential to provide sufficient data across the Mississippi River, if a key methodological challenge can be overcome. Satellites provide data from visible light, but nitrates are only observable with ultraviolet light. We address this methodological challenge by using a two‐step surrogate modelling procedure to link optical data and nitrates in the Lower Mississippi River. First, we correlate in situ nitrate measurements to common water quality parameters, particularly turbidity and chlorophyll, using data from water sensors installed at Baton Rouge, Louisiana, USA, and a long‐term dataset from Louisiana State University. Second, we correlate these water quality data to satellite estimates of water quality parameters. We found a correlation between these water quality parameters and nitrate concentrations, as indicated by a coefficient of determination, when the relationship was viewed in nonlinear parameter space. The spatial extent of the correlation was tested with an upstream nitrate sensor 140 km north of the estimation location. These results provide proof of concept that we can develop models that use satellite data to provide large‐scale monitoring of nitrates across the Mississippi River Basin and other impaired rivers, globally.
Mechanistic Insights of the Ir‐bipyridonate Catalyzed Aqueous Methanol Dehydrogenation and Transfer Dehydrogenation to Acetophenone: Experimental and DFT Study
Authors: Garg Nidhi , Poli Rinaldo , Sundararaju Basker
Published: February 2024

The mechanisms of the Cp*IrIII(bpyOO)‐catalyzed (bpyOO=bidentate (NN) doubly deprotonated 2,2′‐bipyridine‐6,6′‐diol) acceptorless methanol dehydrogenation and acetophenone transfer hydrogenation by methanol under basic conditions have been explored by the combination of 1H NMR, kinetics, and DFT computational studies. During dehydrogenation of methanol and of its dehydrogenated derivatives, the presence of two iridium hydride species (anionic [Cp*Ir(bpyOO)H]−, C* and neutral [Cp*Ir(bpyOOH)H], D*), which interconvert depending on pH, was detected. The DFT studies on a Cp model system highlighted three interrelated catalytic cycles of methanol, formaldehyde and formic acid dehydrogenation, all leading to the same hydride intermediates C and D. The dehydrogenation of methanol prefers a direct β‐hydride transfer pathway from the methoxide ion to Ir, rather than the classical β‐hydride elimination pathway from a coordinated methoxide ligand, but an alternative bifunctional H+/H− transfer with involvement of a ligand O atom may become competitive at lower pH. The transfer hydrogenation of acetophenone using methanol as hydrogen source features species C* as resting state, with the acetophenone reduction being rate‐determining and following the reverse pathway of methanol oxidation, with a first‐order acetophenone decay and a kinetic isotope effect of 2.36±0.09.
Trifluoromethylsulfinylation Reaction of Activated Arenes and Indoles with Trifluoromethanesulfinyl Chloride
Authors: Zhong Tian‐Cheng , Jiang Min , Liu Jin‐Tao
Published: February 2024

The trifluoromethylsulfinylation reaction of activated arenes with trifluoromethanesulfinyl chloride (CF3SOCl) in the presence of Lewis acid was achieved under mild and solvent‐free conditions. A series of aryl trifluoromethyl sulfoxides were obtained in moderate to high yields. The protocol could be extended to the perfluoroalkylsulfinylation of activated arenes, as well as the trifluoromethylsulfinylation of indoles without additive.
From single‐cell cloning to high‐yield influenza virus production – implementing advanced technologies in vaccine process development
Authors: Zinnecker Tilia , Badri Najd , Araujo Diogo , Thiele Kristin , Reichl Udo , Genzel Yvonne
Published: February 2024

Innovations in viral vaccine manufacturing are crucial for pandemic preparedness and to meet ever‐rising global demands. For influenza, however, production still mainly relies on technologies established decades ago. Although modern production shifts from egg‐based towards cell culture technologies, the full potential has not yet been fully exploited. Here, we evaluate whether implementation of state‐of‐the‐art technologies for cell culture‐based recombinant protein production are capable to challenge outdated approaches in viral vaccine process development. For this, a fully automated single‐cell cloning strategy was established to generate monoclonal suspension Madin‐Darby canine kidney (MDCK) cells. Among selected cell clones, we could observe distinct metabolic and growth characteristics, with C59 reaching a maximum viable cell concentration of 17.3 × 106 cells/mL and low doubling times in batch mode. Screening for virus production using a panel of human vaccine‐relevant influenza A and B viruses in an ambr15 system revealed high titers with yields competing or even outperforming available MDCK cell lines. With C113, we achieved cell‐specific virus yields of up to 25,000 virions/cell, making this cell clone highly attractive for vaccine production. Finally, we confirmed process performance at a 50‐fold higher working volume. In summary, we present a scalable and powerful approach for accelerated development of high‐yield influenza virus production in chemically defined medium starting from a single cell.
Life Cycle Assessment of Energy Storage Technologies for New Power Systems under Dual‐Carbon Target: A Review
Authors: Yi Yapeng , Chang Li , Wu Bingxiang , Zhao Junjing , Peng Hu , Li Lingxiao , Wang Aiping
Published: February 2024

Aiming at the grid security problem such as grid frequency, voltage, and power quality fluctuation caused by the large‐scale grid‐connected intermittent new energy, this article investigates the life cycle assessment of energy storage technologies based on the technical characteristics and performance indicators. First, the new power system under dual‐carbon target is reviewed, which is compared with the traditional power system from the generation side, grid side, and user side. Based on the power characteristics of the new power system, the energy storage mechanism and energy storage characteristics of mechanical energy storage, electrochemical energy storage, chemical energy storage, electromagnetic energy storage, and thermal energy storage are described. Then, compared with the existing research strategies, a comprehensive life cycle assessment of energy storage technologies is carried out from four dimensions: technical performance, economic cost, safety assessment, and environmental impact. Moreover, the suitable scenarios and application functions of various energy storage technologies on the power generation side, grid side, and user side are compared and analyzed from the working principle, key technologies, advantages and disadvantages, and technical difficulties of energy storage technologies. Finally, combined with the energy storage technologies in the electricity market, four profit models are analyzed.
Is the Green Total Factor of Energy Efficiency Rising or Falling? Evidence from the Belt and Road Initiative Countries
Authors: Ma Dalai , Guo Zuman , Xiao Yaping , Zhang Fengtai , Peng Guochuan , Zhang Jiawei , An Bitan
Published: February 2024

“The Belt and Road Initiative” (BRI) seeks to attain high‐quality development and sustainability. This study examines the green total factor energy efficiency (GTFEE) of 58 BRI countries from 2005 to 2019 and its influence factors using the Super slacked‐based measurement and Tobit models. The findings indicate that: 1) Singapore and the other seven countries have GTFEEs above 0.9, which is better than other countries; seven out of 58 countries have GTFEEs below 0.5. 2) Due to regional disparities, Southeast Asia, Central, and Eastern Europe have the greatest GTFEE, followed by South Asia, West Asia, and the Commonwealth of Independent States, and the lowest is in Central Asia, China, and Mongolia. 3) Compared to developing economies, developed economies have a higher GTFEE. 4) Between 2005 and 2019, the overall BRI energy efficiency dropped from 0.75 to 0.56. 5) According to Tobit results, for every 1% increase in economic development and energy structure, GTFEE increases by 0.08% and 0.31% points, respectively, and for every 1% increase in trade and land area, GTFEE decreases by 0.04 and 0.05, respectively. Therefore, BRI countries should strengthen international cooperation, develop advanced technologies, and increase the proportion of renewable energy utilization.