bluuebunny/crossref_metadata_2025 huggingface dataset:
Photo‐Assisted Bottom‐Up Synthesis of Orange Phosphorus
Authors: Qiu Pengcheng , Wang Jiameng , Kojima Takahiro , Kazumi Kenji , Sato Hiroyasu , Komatsu Naoki , Fukami Kazuhiro , Sakaguchi Hiroshi
Published: December 2024

A tubular strand of phosphorus composed of vectorially aligned pentagons has been theoretically predicted as a new allotrope of phosphorus with a polar structure, expecting potential applications. However, it has not been successfully synthesized yet due to the difficulty of creating isolated strands to avoid interchain bonding. Here, such an allotrope named “orange phosphorus“ was successfully produced using a photo‐assisted synthesis from an amorphous film of solution‐processable Na2P16 precursors. A green laser irradiation initiated the phase transition of precursors, inducing chemical reactions like topochemical polymerization and rearrangement, creating a 1D chain of orange phosphorus. 3D electron diffraction crystallography showed that the molecular structure of orange phosphorus consists of one‐dimensional polar pentagonal‐tubes made up of [P8]P2[ repeat units. Orange phosphorus demonstrates excellent piezoresistivity due to its high strain‐sensitive 1D chain structure, showing strain‐induced Raman shifts. Its gauge factor exceeds those of 2D materials such as black phosphorus and transition metal dichalcogenides. These findings indicate that orange phosphorus has great potential for use in strain sensor applications.
Extended Tetrathiafulvalene Multi‐Redox Systems Incorporating 4,5‐Dihydroazuleno[2,1,8‐ija]azulene Cores
Authors: Bliksted Roug Pedersen Viktor , Zalibera Michal , Lirette Frédéric , Ouellette Jérémie , Lanza Arianna , Fernández Israel , Rapta Peter , Morin Jean‐François , Brøndsted Nielsen Mogens
Published: December 2024

The introduction of 4,5‐dihydroazuleno[2,1,8‐ija]azulene as a central core between two 1,4‐dithiafulvene (DTF) units provides a novel class of extended tetrathiafulvalene (TTF) electron donors. Herein we present the synthesis of such compounds with the azulenoazulene further expanded by annulation to benzene, naphthalene, or thiophene rings. Moreover, unsymmetrical donor‐acceptor chromophores with one DTF and one carbonyl at the central core are presented. The effect of the odd‐membered rings of the polycyclic aromatic hydrocarbon cores on the geometrical features and the extent of bond conjugation in these systems were investigated by UV/Vis absorption spectroscopy, (spectro)electrochemical studies, X‐ray and electron diffraction, and computational studies. Altogether these studies reveal that, upon oxidation, the non‐planar core of the bis(benzo)‐fused dihydro‐azulenoazulene‐extended TTF generates a large 22π‐aromatic system (together with two 6π‐aromatic 1,3‐dithiolium appendages) characterized by significant bond length equalizations. The dication formed by oxidation is EPR silent, indicating a singlet ground state. Computations reveal that the closed‐shell singlet species and its open‐shell singlet counterpart are nearly degenerate and of lower energy than a triplet species. According to cyclic voltammetry, the compounds can be oxidized further and present multi‐redox systems.
Achieving High Solid–Liquid Ratio through Competitive Coordination towards Efficient Recovery of Metals from Spent Batteries
Authors: Tan Jing , Huang Rui , Li Kunpeng , Yan Xu , Guo Lin , Guo Zaiping , Zhang Wenchao , Chai Liyuan
Published: December 2024

The recycling of critical metals from spent lithium‐ion batteries represents a significant step towards meeting the enhancing resource requirements in the new energy industry. Nevertheless, achieving effective leaching of metals from the stable metal‐oxygen (MO6) structure of spent ternary cathodes and separation of metal products simultaneously still remained a huge challenge towards industrial applications. Herein, a competitive coordination strategy was proposed to design a novel deep eutectic solvent (DESs), which improved both leaching and selective metal recycling capacity even at high solid–liquid ratio (1 : 10). The results demonstrated that the number of hydrogen bonds in designed ternary DESs was 16.5 % higher compared to those in the binary DESs, resulting in efficient reaction kinetics to break the metals‐oxygen bond. More importantly, the competing‐ligand (p‐toluenesulfonic acid) could preferentially enter into the first nanostructure sheath and reduce the proportion of solvated oxalic acid (OxA) from 28.36 % to 17.76 % within the nanostructure, which enable OxA molecules to enhance the coordination interaction with metal for precipitating NiC2O4 ⋅ 2H2O product (~95.7 % purity) from spent cathodes. This work achieved impressive profitability ($16.05 per kg feedstock) and effectively reduction of GHG emissions during the recycling process, making it applicable to critical sustainability initiatives.
Evaluation of Moringa oleifera Incorporated With Zinc Oxide Nanoparticles/Poly(Vinyl) Alcohol Nanofibers as Antibacterial Material
Authors: Murtafi'atin Rini , Kusumaatmaja Ahmad
Published: December 2024

Antibacterial materials are increasingly significant, particularly for biomaterials and food packaging applications. Materials with good elasticity and antibacterial properties are crucial in this line of work. This study focused on the investigation of nanofiber properties in elasticity and antibacterial by combining
Moringa oleifera
(MO) zinc oxide nanoparticles (ZnO NPs) with polyvinyl alcohol (PVA) nanofiber. The PVA/MO/ZnO nanofiber is fabricated using the electrospinning method. The morphology of PVA/MO/ZnO nanofiber shows smooth and uniform fibers with 292 nm in diameter size. The EDX mapping also demonstrates the successful loading of ZnO NPs into fibers, and the tensile test gives modulus Young as 290 MPa, which corresponds to good elasticity or flexibility for biomedical applications. The antibacterial activity of PVA/MO/ZnO nanofiber mats against gram‐positive and gram‐negative microbial species shows a good inhibition zone of 6.84 mm for
Escherichia coli
bacteria. The hydrophilicity of the nanofibers also supported this antibacterial activity. These results show that PVA/MO/ZnO nanofiber is certainly a potential material that has good elasticity and antibacterial properties, which may be useful in biomaterial applications, food packaging, and coating material. It also suggested the simple preparation of an antibacterial material with good elasticity.
Discovery of xanthone‐based nitric oxide donors targeting biofilm clearance
Authors: Tang Qun , Ye Wenchong , Chandarajoti Kasemsiri , Ge Rile , Lv Sai , Zhang Keyu , Han Xiangan , Wang Chunmei , Bai Han , Wang Xiaoyang , Zhou Wen
Published: December 2024

Bacteria biofilm infection seriously challenges clinical drug therapy. Nitric oxide (NO) was reported to disperse biofilm, eliminate bacteria resistance and kill bacteria. In this study, on the basis of membrane targeting of α‐mangostin (α‐MG) and the dispersion effect of NO on bacteria biofilms, we designed and synthesized 30 NO donors that α‐MG was conjugated with a nitrobenzene or a nitrate and other four representative reference derivatives. Compound 23 with 2‐chloro‐4‐nitrobenzoyl introduced in the position C6 of α‐MG exhibited the prominent ability to eradicate Staphylococcous aureus biofilm, and a more long‐lasting and stable bactericidal effect in vitro, and lower hemolytic activity over α‐MG. Moreover, a mouse wound model infected by S. aureus biofilm supported the in vivo reduced bacterial burden closely associated with the NO release from compound 23 that exerted a dispersing effect on biofilms. Therefore, our design strategy can provide a promising and effective solution to intervene in biofilm infection with high specificity.
Effect of Protonation‐Induced Distortions on the Spectral Properties and Electronic Structure of Octaphenylporphyrins through UV‐Vis and VT‐NMR Spectral, Electrochemical and Ab Initio Studies
Authors: Rana Nivedita , Kumari Soni , Sankar Muniappan
Published: December 2024

The extent of conformational change of the porphyrin macrocycle during the course of protonation was observed, both experimentally and theoretically. For synthesised β‐substituted octaphenylporphyrin (OPP) ring systems, these macrocyclic distortions have been investigated by spectrophotometric titrations, electrochemical, variable temperature nuclear magnetic resonance (VT‐NMR) and computational analysis. Protonation‐induced non‐planarity in a macrocyclic system is experimentally observed in a single step during spectrophotometric titration. The addition of trifluoroacetic acid (TFA) eventually formed dicationic form while tetrabutylammonium hydroxide (TBAOH) was employed for deprotonation study for titration in toluene. The progress of the protonation i. e. the addition of proton to the core of the ring was monitored by UV/Vis spectroscopy, which was also determined logβ value. The spectral changes demonstrate the conformational flexibility of these macrocyclic systems correlating with the photophysical properties. The degree of nonplanarity exhibited incremental progress in response to protonation, with a specific order observed: H2TPP<H2OPP<H2OPPBr4<H2OPPBr3NO2. VT‐NMR experiments were carried out in dichloromethane over a temperature range of 193–298 K, providing dynamic behaviour of these systems. Furthermore, our study delved into the structural aspects, frontier molecular orbitals and ground state energies of H4P(CF3COO)2 and absorption bands computed at the TD‐B3LYP/6‐31G level of theory, anticipated a red shift in both the Soret and Q0,0 bands. This theoretical prediction aligns seamlessly with the experimental findings from spectrophotometric titrations, providing validation to our computation insights. In summary, this comprehensive study elucidates the extent of conformational changes occurring in β‐substituted octaphenylporphyrin (OPP) ring systems upon protonation and deprotonation.
Salts of trans‐3‐Styryl Pyridine: The Effect of N‐Quaternization on Solid‐State Photoreactivity, and Photochemical Crystal Melting
Authors: Kubendiran Banu , Kurakula Uma , Baskar Shyamvarnan , Medishetty Raghavender , Kole Goutam Kumar
Published: December 2024

Investigating solid‐state photoreactivity, driven by crystal packing, has been a major enduring research theme in Crystal Engineering. Trans‐3‐styryl pyridine (3‐StPy), an unsymmetric olefin, is photo‐stable. However, when converted to a series of salts, they exhibited solid‐state photoreactivity under UV irradiation. Crystal structures of 3‐StPy, its protonated salts, namely, (3‐StPyH)(HSO4) ⋅ H2O (1), (3‐StPyH)(CF3CO2) (2), and (3‐StPyH)(p‐Tol‐SO3) (3), and methylated salt (3‐StPyMe)I (4) were determined by X‐ray diffraction. 3‐StPy molecules were found not to align in the parallel arrangement required to undergo solid‐state [2+2] photocycloaddition reaction; however, upon protonation and methylation, the unsymmetric 3‐StPyH+ and [3‐StPyMe]+ cations aligned in a head‐to‐tail parallel arrangement, predominantly governed by the cation⋅⋅⋅π interactions. Various structural features, e. g., the patterns of hydrogen bonding, etc. have been addressed, and established by Hirshfeld surface analysis. The salt with p‐tolyl sulfonate anion (3) with Z′>1 represents a rare crystal class. It was also noted that the crystals of 1 and 2 melted into a liquid state upon photodimerization reaction. UV‐vis absorption and fluorescence properties have been explored. The electronic structures of 3‐StPy, 3‐StPyH+, [3‐StPyMe]+, and the dimer [3,3′‐MPyPhCB]2+ cations have been elucidated by DFT calculations, and the effect of N‐quaternization on crystal structures and photophysical properties has been discussed.
Recyclable copper catalyst supported over ceria for acceptorless dehydrogenative synthesis of quinolines
Authors: Parsai Priya , Choudhary Neha , Sahu Rajib , Mobin Shaikh M.
Published: December 2024

This study presents a highly efficient and cost‐effective Cu/CeO2 catalyst for the acceptorless dehydrogenative coupling (ADC) of o‐aminobenzyl alcohols and secondary alcohols to synthesize quinolines. The catalyst demonstrated over 90% yield in quinoline production under mild conditions, exhibiting excellent tolerance to various functional groups. The Cu/CeO2 catalyst, synthesized via a co‐precipitation method, was thoroughly characterized through various techniques like PXRD, XPS, and AC‐STEM. Control experiments confirmed the ADC pathway, where both alcohol substrates underwent dehydrogenation, forming key intermediates that subsequently condensed to produce quinolines. This catalytic system, offering recyclability and high efficiency, is a promising alternative to noble metal‐based catalysts for sustainable quinoline synthesis.
Deracemization of Benzoin and its Derivatives via Kinetic, Dynamic Kinetic, Aerobic Oxidative Kinetic and Reagent‐mediated resolution
Authors: Ummareddy Venkata Subba Reddy , Kothapalli Raveendra Babu , Bheemreddy Anusha , Marri Naveen Kumar , P Sundar Singh , S Ramakrishna
Published: December 2024

The production of enantiomerically pure compounds remains a vital and valuable objective in modern organic chemistry due to their broad applications in fields such as biosensing, optics, electronics, photonics, catalysis, nanotechnology, and drug or DNA delivery. Optically pure α‐hydroxy ketones, in particular, are key structural components in many drugs and natural products with significant biological activity. Among these, benzoin type α‐hydroxy ketones, which possess two adjacent functional groups, a carbonyl and a hydroxy group, are especially important. These functional groups can be easily transformed into the significant organic compounds such as 1,2 amino alcohols and 1,2 diols etc, which are important intermediates for synthesis of high profile biological active natural products. Deracemization of racemic compounds remains one of the most effective strategies for producing optically pure compounds, despite recent advances in asymmetric synthesis. Many research groups have developed various methods for resolving racemic benzoins, including kinetic resolution, dynamic kinetic resolution, metal‐catalyzed aerobic oxidative kinetic resolution, and reagent‐mediated resolution. In this context, we aim to provide a comprehensive review of the various resolution methods applied specifically to racemic benzoins. To the best of our knowledge, no comprehensive review on the resolution of racemic benzoins has been published to date.
The Surprising Long‐Term Evolution of the ULXP NGC 7793 P13
Authors: Fürst Felix , Walton Dominic J. , Bachetti Matteo , Earnshaw Hannah , Brightman Murray
Published: December 2024

The ultra‐luminous x‐ray pulsar (ULXP) NGC 7793 P13 has been regularly monitored with XMM‐Newton, NuSTAR, and Swift for the last 8 years. Here, we present the latest results of this monitoring campaign with respect to the pulse period evolution and spectral variability. We find that since the source recovered from an x‐ray low state in 2020–2022 the spin‐up rate has increased significantly compared with before the off‐state, even though the x‐ray luminosity has not shown an equivalent increase. We find that the x‐ray and optical/UV flux are anti‐correlated, and speculate that this variability might be driven by a large accretion disk, precessing at a super‐orbital period of 7–8 years. We study the spectral behavior in the XMM‐Newton and NuSTAR data, and find very little changes in the spectral shape, despite the large flux variability. This spectral consistency provides further indication that the observed flux variability is a geometric effect and not due to intrinsic changes of the accretion rate.
Examining the Relationship Between Parental Broader Autism Phenotype Traits, Offspring Autism, and Parental Mental Health
Authors: El‐Bouhali‐Abdellaoui Fátima , Voltas Núria , Morales‐Hidalgo Paula , Canals Josefa
Published: December 2024

Broader Autism Phenotype (BAP) traits may be present in parents of children on the autism spectrum. However, the prevalence and impact of these traits on parental mental health is poorly understood. We explore BAP traits and its relationship to mental health in 228 fathers and 261 mothers from a sample of 266 scholars from the EPINED study (Spain) grouped as follows: non‐autism (N = 122), autism traits (N = 93: 38 subthreshold autism and 55 autism symptoms) and autism (N = 51). BAP rates were higher in fathers (36.9%) than in mothers (26.1%). Moreover, BAP was significantly more frequent in fathers of autistic children (52.3%) than in fathers of children without autistic traits (28.0%), with no differences between autistic conditions groups. Mothers of autistic children exhibited higher psychological distress (36.0%) than mothers of comparison group (19.2%). Fathers with BAP obtained significantly higher scores in emotional problems than fathers without BAP. Multivariate analyses showed that, fathers' emotional problems were associated with their BAP traits, whereas in mothers they were associated with having a child with autism as well as the child's emotional dysregulation. Identifying BAP in parents of autistic conditions children can help professionals to provide specific strategies for improving the well‐being of children and parents.
Research on Intelligent Monitoring and Concentration Prediction for Penicillin Fermentation Process
Authors: Zhang Yin , Zhang Kai , Hu Ting , Yuan Libo
Published: December 2024

In the biopharmaceutical industry, accurately predicting penicillin concentration during fermentation is key to boosting production efficiency and quality assurance. This study leverages the PenSim simulation data set and applies various machine learning and deep learning techniques to forecast penicillin fermentation concentration. Initially, through correlation analysis, nine feature variables with significant impacts on penicillin concentration were screened, and the data underwent preprocessing and standardization. Using grid search, we systematically optimize the hyperparameters of various prediction models. Results show that the ridge regression model excels, achieving a mean squared error of 0.0512 and a mean absolute error of 0.0361. This indicates a strong linear relationship between penicillin concentration and the selected features. Our study offers data‐driven insights for intelligent monitoring and optimization of penicillin fermentation processes. It also showcases the potential of artificial intelligence in enhancing control of biotechnological facilities, paving the way for future research.
Quorum sensing inhibition evaluation method: An experiment‐based microbiology laboratory course
Authors: Luís Ângelo , Domingues Fernanda
Published: December 2024

Bacteria have developed a cell‐to‐cell communication system called quorum sensing (QS), allowing them to regulate group behavior and synchronize the expression of virulence factors, responsible for increasing their infection capacity and resistance to antimicrobials. Although the control of microbial infections through the inhibition of microbial growth has traditionally been the basis of antimicrobial chemotherapy, the emergence of antimicrobial resistance has led to the search for new microbial control strategies, namely through the inhibition of QS. Among the agents studied to inhibit this bacterial communication are essential oils (EO), which are considered very effective QS inhibitors. When searching for new QS inhibitor agents, it is essential to have a cheap and easy‐to‐perform method that allows the evaluation of this activity. Chromobacterium violaceum is a Gram‐negative bacterium that has been widely used as a model organism in QS research laboratories because it produces the violet‐colored pigment violacein, which is regulated by QS and is an easily observable and quantifiable characteristic marker. The objective of this work is to describe a method to evaluate the inhibition of the QS using Cymbopogon martinii EO as a potential inhibitory agent for violacein production by C. violaceum, which can be applied in the Microbiology laboratory course as a part of the programs of several science degrees. The proposed method is inexpensive and does not require specific equipment, enabling its easy implementation by the laboratory team and professors.
5‐Hydroxymethylcytosine Profiles of cfDNA in Urine as Diagnostic, Differential Diagnosis and Prognostic Markers for Multiple Myeloma
Authors: Xie Weiwei , Li Xuehui , Chen Hangyu , Chu Jinlin , Zhang Lei , Tang Bo , Huang Wenrong , Li Linlin , Lin Jian , Dong Yujun
Published: December 2024

Background

An effective urine‐based method for the diagnosis, differential diagnosis and prognosis of multiple myeloma (MM) has not yet been developed. Urine cell‐free DNA (cfDNA) carrying cancer‐specific genetic and epigenetic aberrations may enable a noninvasive “liquid biopsy” for diagnosis and monitoring of cancer.

Methods

We first identified MM‐specific hydroxymethylcytosine signatures by comparing 64 MM patients, 23 amyloidosis (AM) patients and 59 healthy cohort. Then, we applied a machine learning algorithm to develop diagnostic and differential diagnosis model. Finally, the prognosis of MM patients was predicted based on their survival time at the last follow‐up.

Results

We identified 11 5hmC markers using logistic regression algorithm could effectively diagnosis MM (AUC = 0.902), and achieved 85.00% specificity and 85.71% sensitivity. These 11 markers could also effectively differential diagnosis MM (AUC = 0.805) with 88.89% specificity and 73.08% sensitivity. In addition, the prognostic prediction model also effectively predicted the prognosis of patients with MM (p < 0.01), of which 4 differential markers (RAPGEF2, BRD1, TET2, TRAF3IP2) could independently predict the prognosis of MM.

Conclusions

Together, our findings showed the value of urine cfDNA hydroxymethylcytosine markers in the diagnosis, differential diagnosis and prognosis of MM. Meantime, our study provides a promising and completely non‐invasive method for the diagnosis, differential diagnosis and prognosis prediction of MM.
Design, Synthesis, and Biological Evaluation of Novel Trifluoromethylated Dipeptide Mimetics of Matijin‐Su as Potent Anti‐HBV Agents
Authors: Shao Xiaoshuang , Kuang Anxiang , Xu Guangcan , Yu Gang , Xu Bixue , Kong Xiangkai , Meng Xueling , Zeng Xiaoping
Published: December 2024

A series of Matijin‐Su (MTS) derivatives were designed, synthesized and their anti‐hepatitis B virus (HBV) activities were evaluated in vitro. Twelve compounds displayed good inhibitory activity against HBV DNA replication with IC50 values at micromolar level (0.14–4.81 µM), and among them, compounds 13d, 13n, and 13o were selected for further study. Compound 13d suppressed the HBeAg secretion with IC50 value of 2.57 µM (SI = 4.31), while had no effect on HBsAg. However, compounds 13n and 13o showed no effect to both HBeAg and HBsAg. The molecular docking studies indicated that compound 13d could form H‐bond interaction with protein residues of HBV core protein which deserves further study.
Unlocking the Potential of Carrier Mediated Nano‐biomedicine in Management of Diabetes Mellitus: A Review
Authors: Mistry Priya S , Singh Sudarshan , Chorawala Mehul R , Prajapati Bhupendra G , Kapoor Devesh U
Published: December 2024

Diabetes is a medical condition that belongs to the group of chronic diseases that affect how the body processes glucose, the primary source of energy for cells. Glucose comes indirectly from the consumed food and is carried by bloodstream to various cells in the body. Insulin, a hormone synthesized by the pancreas plays a vital role in the conversion of glucose to energy. Managing diabetes involves regular monitoring of blood sugar levels, adopting a healthy diet, engaging in regular physical activity, and taking medications or insulin as prescribed by a healthcare provider. Proper management of diabetes may lead to the prevention or delay of diabetic complications may further sever other diseases associated impediment. Drug delivery in the management of diabetes is designed to administer insulin or other diabetes medications in a controlled and convenient manner. Recently nanotechnology has emerged as a transformative approach in the management of diabetic complications, particularly through carrier‐mediated nano‐biomedicine. Several natural products have been studied and reported for their potential role in managing diabetes. While they may not replace standard medical treatments, some of these natural products could complement existing therapies and support overall diabetes management. Therefore, this review explores the potential of nanocarriers to enhance drug delivery systems for diabetes mellitus treatment, addressing the limitations of conventional therapies that often suffer from poor bioavailability and frequent dosing requirements. Studies have demonstrated that bridging these bioactive compounds significantly enhance the therapeutic efficacy in the management of diabetes. Challenges remain in translating these technologies from laboratory settings to clinical applications; however, the potential benefits for improving glycemic control and overall quality of life for diabetic patients are substantial. Future research should focus on optimizing these nano‐biomedicine strategies to realize their full therapeutic potential in diabetes management.
GC–MS Analysis, Neuropharmacological, and Antidiarrheal Activities of the Acetone Extract of Najas gracillima Seaweed: In Vivo and In Silico Study
Authors: Ali Md. Liakot , Meem Jannatul Naima , Hoque Neamul , Jalil Muhammad Abdul , Chowdhury Sajjad Hossen , Khastagir Sristy , Rashed Mohammad , Hoque Fahmina , Alarfaj Abdullah A. , Ansari Mohammad Javed , Alharbi Sulaiman Ali , Hossen S. M. Moazzem
Published: December 2024

Najas gracillima, a marine seaweed found in North America and Asia, was investigated for its neuropharmacological and antidiarrheal properties. Acetone extracts of N. gracillima (ANG) were analyzed using both in vivo and in silico methods. Gas chromatography–mass spectrometry (GC–MS) analysis was conducted to identify bioactive compounds present in the extract. In vivo assessments, including the elevated plus maze, light–dark box, and hole board tests, showed that ANG at doses of 200 and 400 mg/kg exhibited significant (p < 0.001) anxiolytic effects. Both doses also demonstrated antidepressant effects in the forced swimming and tail suspension tests by significantly (p < 0.001) reducing immobility time, with the 200 mg/kg dose showing more pronounced effects. Sedative activity was confirmed through open field and hole cross tests, where both doses exhibited significant (p < 0.001) sedative effects. ANG also demonstrated significant antidiarrheal effects at 400 mg/kg in castor oil‐induced diarrhea (p < 0.05) and gastrointestinal motility tests (p < 0.01). Molecular docking simulations revealed that compounds from ANG had strong binding affinities to critical drug targets involved in anxiety, depression, sleep disorders, and diarrhea. These findings suggest that N. gracillima holds potential for therapeutic use in treating neuropharmacological disorders and diarrhea, warranting further investigation.
Novel Tetrapeptides, Tengupeptins A and B, Produced by Lecanicillium aphanocladii FKI‐9593 Fungal Strain
Authors: Kojima Hiroki , Watanabe Yoshihiro , Higo Mayuka , Kasuya Taiga , Nonaka Kenichi , Iwatsuki Masato , Sugawara Akihiro
Published: December 2024

The discovery of novel natural products through the exploration of distinct microorganisms is crucial for advancing drug discovery research. In this study, we focus on a unique environmental resource, microbial masses known as “Tengu‐no‐Mugimeshi.” From the culture broth of Lecanicillium aphanocladii FKI‐9593, isolated from Tengu‐no‐Mugimeshi collected at Mount Kurohime, Nagano Prefecture, Japan, we report the isolation of two novel tetrapeptides, tengupeptins A (1) and B (2), as well as the known compound oosporein. Structural analysis revealed that tengupeptins are composed of four amino acids: L‐glutamic acid for 1 (or L‐pyroglutamic acid for 2), (Z)‐α,β‐didehydro tryptophan (ΔZTrp), (Z)‐α,β‐didehydro‐phenylalanine (ΔZPhe), and L‐aspartic acid. Notably, dehydroamino acids containing an aromatic moiety conjugated with a double bond connected via two or more consecutive linkages are rare in natural products, and the ΔZTrp‐ΔZPhe fragment represents the first example. The isolation of secondary metabolites from filamentous fungi inhabiting unique environments, such as Tengu‐no‐Mugimeshi, is anticipated to offer significant potential for future research.
Structural and Functional Mimicry of the Antimicrobial Defensin Plectasin by Analogues with Engineered Backbone Composition
Authors: Harmon Thomas W. , Song Junming , Gulewicz Andrew J. , Di Y. Peter , Horne W. Seth
Published: December 2024

The threat posed by bacteria resistant to common antibiotics creates an urgent need for novel antimicrobials. Non‐ribosomal peptide natural products that bind Lipid II, such as vancomycin, represent a promising source for such agents. The fungal defensin plectasin is one of a family of ribosomally produced miniproteins that also exert antimicrobial activity via Lipid II binding. Made up entirely of canonical amino acids, these molecules are potentially more susceptible to degradation by protease enzymes than non‐ribosomal counterparts. Here, we report the development of proteomimetic variants of plectasin through the systematic incorporation of artificial backbone connectivity in the domain. An iterative secondary‐structure‐based design scheme yields a variant with a tertiary fold indistinguishable from the prototype natural product, potent activity against Gram positive bacteria, and low mammalian cell toxicity. Backbone modification is shown to improve oxidative folding efficiency of the disulfide‐rich scaffold as well as resistance to proteolytic hydrolysis. These results broaden the scope of design strategies toward protein mimetics as well as folds and biological functions possible in such agents.
Chemically Robust Cationic Porous Organic Polymer (POP) for Selective Detection and Removal of ReO4− as a Surrogate of Radioactive 99TcO4−
Authors: Biswas Kishalay , Dam Gourab K. , Mahanta Supriti , Roy Anirban , Vinod Parmar Saurabh , Avasare Vidya , Ghosh Sujit K.
Published: December 2024

The efficient removal of 99TcO4− from alkaline nuclear waste is vital for optimizing nuclear waste management and safeguarding the environment. However, current state‐of‐the‐art sorbent materials are constrained by their inability to simultaneously achieve high alkali resistance, rapid adsorption kinetics, large adsorption capacity, and selectivity. In this study, we synthesized a urea‐rich cationic porous organic polymer, IPM‐403, which demonstrates exceptional chemical stability, ultrafast kinetics (~92 % removal within 30 seconds), high adsorption capacity (664 mg/g), excellent selectivity, along with multiple‐cycle recyclability (up to 7 cycles), making it highly promising for the removal of ReO4− (surrogate of 99TcO4−) from nuclear wastewater. Notably, after exposure to 1 M NaOH solution for 24 hours, IPM‐403 maintained a high adsorption capacity of 421.3 mg/g for ReO4−. Furthermore, IPM‐403 acts as an efficient sensor for ReO4−, exhibiting a turn‐on response and a detection limit as low as 78.8 ppb.
Tuning the Duplex Stability of DNA Oligonucleotides Containing Metal‐Mediated Base Pairs of Imidazole‐Derived Nucleobases
Authors: Bardehle Carla , Müller Jens
Published: December 2024

Two artificial imidazole‐derived nucleobases, HQIm (3H‐imidazo[4,5‐f]quinolin‐5‐ol) and CaIm (imidazole‐4‐carboxylate), were introduced into short DNA duplexes to systematically investigate their thermal stability upon metal ion coordination. Metal‐mediated base pairs are formed with the 3d metal ions CoII, NiII and ZnII, as well as with the lanthanoid ions EuIII and SmIII, which induce a thermal stabilization of up to 8 °C upon binding. The latter are the first lanthanoid‐mediated base pairs involving only four donor atoms that result in a significant duplex stabilization. For the 3d metal ions, the increase in DNA melting temperature is in agreement with the trend in complex stability according to the Irving‐Williams series. The duplex stabilization upon metal‐mediated base pair formation depends on the identity of the artificial base pair, enabling discrimination between metal ions by systematic design of the duplex. Further, the influence of pH on the stability of selected duplexes was studied, revealing a linear relation between pH and the formation of HQIm–NiII–HQIm base pairs and allowing to induce a distinct stabilization between 1 °C and 28 °C. Regarding EuIII‐mediated base pairs, an acidic pH can be utilized to disturb their formation, presumably by promoting the coordination of EuIII to the DNA backbone.
Selective Decarboxylative Fluorination of β‐Keto Acids in Aqueous Media: 19F‐NMR‐Assisted Batch Optimization and Transfer to Continuous Flow
Authors: Cermjani Egzon , Deckers Christoph , Maskos Michael , Rehm Thomas H.
Published: December 2024

The selective decarboxylative fluorination of 3‐oxo‐3‐phenylpropionic acid is used as a benchmark reaction to optimize it under biocompatible conditions in batch and to transfer it to continuous flow mode. The reaction conditions are varied with respect to temperature, fluorinating reagents, inorganic base additives, and pH, as these parameters have been identified as having a significant impact on the process. The formation of the products and any by‐products is analyzed using gas chromatography (GC) and 19F nuclear magnetic resonance spectroscopy (NMR). Once optimal conditions have been determined, the reaction is carried out using an automated continuous laboratory synthesis system that features a mesostructured capillary reactor and an integrated 19F‐NMR spectrometer for real‐time monitoring of the reaction. The work presented here represents the initial phase of a multi‐step continuous flow process that will include additional biocatalyzed downstream reactions in future applications.
Enhancing Epoxy Composites with Graphene and Graphene Oxide: Thermal and Mechanical Insights
Authors: Wilczewski Sławomir , Nowak Zdzisław , Maj Michał , Osial Magdalena , Minikayev Roman , Giersig Michael
Published: December 2024

This paper shows the graphene and graphene oxide nanoflakes as the 0.1, 0.5, 1, 2, and 4 wt.% reinforcement of epoxy‐resin matrix to enhance the thermal and mechanical characteristics of the composite. Experimental measurement of the glass transition temperature and thermal expansion coefficient indicated that the addition of nanostructural filler improving the glass transition temperature about ~12 °C for nanocomposite filled carbon‐based nanoparticles for both heating and cooling cycles compared to the bare epoxy resin. Young's elastic modulus measured by nanoindentation and the stress versus strain curves for different weight fractions of graphene nanoflakes additives during uniaxial compression and tension considered were obtained from the experiments. The distributions of logarithmic strain field for the transverse, axial and shear components on the nanocomposites sample surfaces, during the uniaxial tension process for quasi‐static strain rates, were analyzed. The tensile strengths show improvement for nanocomposites with less than 1 % weight fraction of carbon‐based nanoparticles. The compressive yield stress increased to a maximal value (at the recorded peak on the curve) for an epoxy nanocomposite having 2 wt.% oxidized graphene flakes, where both parameters were enhanced with the oxidized form of graphene for the more effective dispersion in the epoxy resin matrix over the bare graphene filler.
Interplay between Spinmerism and Spin‐Orbit Coupling for a d2 Metal Ion in an Open‐Shell Ligand Field
Authors: Roseiro Pablo , Shah Ashini , Yalouz Saad , Robert Vincent
Published: December 2024

Recent theoretical studies have shown that placing a spin‐crossover ion in a field of radical ligands can induce local superpositions of spin states (see Ref. [1,2]). The stability of this phenomenon, termed spinmerism, is called into question when spin‐orbit coupling is included. Thus, we investigate the competition between spinmerism and spin‐orbit coupling in a d2 metal ion with two radical ligands. Our results show that competition between spinmerism and spin‐orbit coupling can induce distinct states which may potentially open new avenues for quantum technologies.
Antimicrobial Potential of a Formazanate‐Based Mercury(II) Complex: In Vitro‐ and In Silico‐Based Insights
Authors: Birara Sunita , Kumar Yadav Vinay , Kumar Jena Abinash , Bhattacharyya Sudipta , Metre Ramesh K.
Published: December 2024

Herein, we present a distorted square pyramidal mercury complex, [HgII(L)Cl] (1), based on a quinoline‐substituted formazan ligand LH[3‐Cyano‐1,5‐(quinolin‐8‐yl)formazan], which was evaluated for its anti‐bacterial activity in vitro. Complex 1 was prepared by refluxing 3‐Cyano‐1,5‐(quinolin‐8‐yl)formazan ligand and mercury chloride(II) in equimolar quantity and was characterized utilizing a range of analytical methods, including single crystal X‐ray diffraction (SCXRD) technique. The crystal packing in complex 1 has been elucidated using supramolecular investigations, which have shown the presence of fascinating Hg−Cl⋅⋅⋅Hg intermolecular spodium bonds of the order 3.348 Å. The antimicrobial activity of the formazanate‐based mercury(II) complex (1) was assessed against Gram‐positive (Staphylococcus aureus and Bacillus subtilis) and Gram‐negative (Escherichia coli and Pseudomonas aeruginosa) bacterial pathogens. In addition, the plausible therapeutic target of the formazanate‐based mercury(II) complex was determined through in silico pharmacophore‐guided rational drug designing approach. Based on the in silico results, a conceivable molecular mechanism of the observed bactericidal action of the newly synthesized [HgII(L)Cl] complex (1) has also been suggested.
FeCu−N6−C Diatomic Sites Catalyst for the Boosted Oxygen Reduction Reactions in Zinc‐Air Batteries
Authors: Sang Longrun , Zhu Haosheng , Zhang Shan , Wang Shipeng , Jiao ZiPan , Wang Yunsi , Zhang Peng , Hu Riming , Liu Bingxin , Li YongCheng
Published: December 2024

Due to the high catalytic activity and stability for oxygen reduction reaction, N‐coordinated Fe−Cu dual‐metal doped carbon material (FeCu−N−C) is considered to be one of the promising electrode materials for metal‐air battery and fuel cells. Herein, FeCu−N−C dual‐metal catalysts was synthesized by an adsorption‐calcination strategy. The prepared FeCu−N−C exhibited high activity and stability both in alkaline and acidic media. In alkaline/acid medium, the half‐wave potential reaches to 0.90/0.80 V, which is better than Fe−N−C catalyst. The power density for FeCu−N−C in zinc‐air battery reaches to 220 mW cm−2 and shows high electrochemical stability for more than 600 hours in charge/discharge cycles, much higher than 130 hours for Pt/C (40 %) and 100 hours for Fe−N−C. Density‐functional theory calculations showed that the FeCu−N−C dual‐metal catalysts got lower overpotential of 0.50 V than Fe−N−C (0.53 V), which improved the ORR activity. The results are helpful for the deep understanding of high‐performance diatomic catalysts.
Visible‐Light‐Induced Tandem Cyclization of 1,7‐Enynes to Access Phenanthridin‐6(5H)‐Ones Using a Polydimethylsiloxane (PDMS) Based Microreactor
Authors: Ravi Dharavath , Prasad Vadla Shiva , Rao Vadithya Ranga , Krishna Silari Mohana , Kumar Chelukalapally Anil , Saha Biswajit , Adiyala Praveen Reddy
Published: December 2024

We report an organophotoredox‐catalyzed visible‐light‐induced tandem cyclization of 1,7‐enynes with diaryliodoniumtriflates has been established leading to Phenanthridin‐6(5H)‐one derivatives under metal‐free conditions. This transformation is initiated by visible light induced aryl radical formation from diaryliodoniumtriflates, followed by its regioseletive addition to the acrylate moiety of 1,7‐enynes then undergoes intramolecular 6‐exo‐dig cascade radical annulation and which is terminated by single electron oxidation along with proton abstraction. This effective, sustainable and metal‐free protocol exhibits a broad substrate scope and excellent tolerability towards various functional groups in good to excellent yields. Further implementation of a batch protocol to continuous flow protocol utilizing polydimethylsiloxane (PDMS) based microreactor exhibits its efficiency.
Dynamic Modeling of LLC Resonant Converter Using Extracted Two‐Harmonic Approximation and Comparative Analysis With Other Approaches
Authors: Abbasi Ahmad , Ghayebloo Abbas
Published: December 2024

Resonant converters are widely used in various applications due to their wide input voltage range, high efficiency, and high power density. The mathematical modeling of these converters has great importance because they have both AC and DC states, simultaneously, which poses challenges for controller design. In this paper, a dynamic mathematical model of the LLC resonant converter is extracted by developing the common first harmonic approximation (FHA) model to a two‐harmonic approximation (THA) model, and its accuracy is compared with other conventional models, including the FHA, the dynamic pharos (DP), non‐linear mathematical models. As a reference model, circuit experimental model has been used for comparison. The comparison metric is the sum of squared errors in transient and steady‐state modes, expressed as a percentage of the steady‐state peak value. Furthermore, the output of the mathematical models and simulations is evaluated against practical results from a prototype.
Efficient Input‐Output Feedback Linearizing Control of BLDC Drives
Authors: Joshi Dhaval , Deb Dipankar , Giri Ashutosh K. , Colak Ilhami
Published: December 2024

Electrically driven unmanned aerial vehicles (UAVs) are gaining popularity due to use in industrial, military, and civil applications. The UAVs have to execute complicated maneuvers in the air requires accurate control of the BLDC motor propeller systems. In this study, we propose easy to implement field‐oriented adaptive input‐output feedback linearizing control (AIOFL) for controlling propellers as per demand of flight controller. This study aims to compare the proposed field‐oriented AIOFL with usual six step control architecture with a focus on the typical back‐electromotive force (back‐EMF) shapes featured in the propeller motor. The proposed control architecture that does not only regulate speed and torque of the propeller with acceptable torque ripple but it also estimates the rotor magnetic flux and the stator resistance of the BLDC motor to know about stator/rotor condition monitoring, motor fault detection, and temperature rise. To ensure reliable operation in all operational conditions, closed loop stability of proposed speed controller is analyzed based on the Lyapunov method. Particle swarm optimization (PSO) is utilized to accurately tune the PI controller since the trial‐and‐error technique used to choose the PI controller gains resulted in the low stability and poor transient response of the controller. Finally, comprehensive numerical and experimental tests are performed and compared with conventional field‐oriented control to evaluate the effectiveness and robustness of the proposed control system.
The Interplay Between Visual Traits and Forest in Bumblebee Communities Across Sweden
Authors: Tichit Pierre , Kendall Liam , Olsson Peter , Taylor Gavin , Rau Christoph , Caplat Paul , Smith Henrik G. , Baird Emily
Published: December 2024

Understanding how ecological communities assemble in relation to natural and human‐induced environmental changes is critical, particularly for communities of pollinators that deliver essential ecosystem services. Despite widespread attention to interactions between functional traits and community responses to environmental changes, the importance of sensory traits has received little attention. To address this, we asked whether visual traits of bumblebee communities varied at large geographical scales along a habitat gradient of increased tree cover. Because trees generate challenging light conditions for flying insects, in particular a reduced light intensity, we hypothesised that differences in tree cover would correlate with shifts in the visual and taxonomical composition of bumblebee communities. We quantified 11 visual traits across 36 specimens from 20 species of bumblebees using micro‐CT and optical modelling of compound eyes and ocelli, and investigated how these traits scale with body size. Using an inventory of bumblebee communities across Sweden and our visual trait dataset, we then explored how visual traits (both absolute and relative to body size) differed in relation to tree cover. We found positive shifts of the community weighted means of visual traits along the increasingly forested habitat gradient (facet diameter, inter‐ommatidial angle, eye parameter of the compound eye and alignment of the three ocelli) that were consistent regardless of body size, while other traits decreased when more forest was present in the landscape (facet number). These functional patterns were associated with differences in the abundance of six common species that likely explains the community‐wide shift of visual traits along the habitat gradient. Our study demonstrates the interaction between vision, habitat and community assembly in bumblebees, while highlighting a promising research topic at the interface between sensory biology and landscape ecology.
Authentication of Virgin Olive Oil Based on Untargeted Metabolomics and Chemical Markers
Authors: Dou Xinjing , N´Diaye Katharina , Harkaoui Said El , Willenberg Ina , Ma Fei , Zhang Liangxiao , Li Peiwu , Matthäus Bertrand
Published: December 2024

Virgin extra olive oil as a high‐value edible oil is a potential object of adulteration. Refined camellia oil (RCO) could be one of the most challenging potential adulterants of olive oil to detect due to its high similarity in the fatty acid composition. In this study, an untargeted metabolomics strategy based on data from ultra‐performance liquid chromatography‐electrospray ionization‐quadrupole‐time of flight (UPLC‐ESI‐qTOF) measurements combined with statistical methods was applied to identify the unauthorized addition of RCO to extra virgin olive oil (EVOO). Untargeted fingerprints of the olive oil and RCO could be classified into two groups via unsupervised principal component analysis (PCA) that shows the significant difference of the fingerprints of polar components extracted from olive oil and CAOs, respectively. Orthogonal partial least squares‐discriminant analysis (OPLS‐DA) and volcano plots were used to identify markers with significant difference between these two oils. The results show that 927 and 780 features (positive and negative ESI modes), respectively, were higher regulated in virgin extra olive oil, whereas 439 and 479 features, respectively, were higher regulated in RCO. From these features, 28 markers for olive oil and 7 markers for CAO were tentatively identified. Further adulteration experiments showed that virgin extra olive oil containing more than 15% RCO could be distinguished from the olive oil by this untargeted UPLC‐ESI‐qTOF measurement, followed by unsupervised PCA. Furthermore, camelliagenin A (519.3695/12.22, [M + FA − H]−) could still be detected when EVOOs were mixed with at least 5% CAO.
Facile Access to Phospholene Fused Polycycles through Intramolecular Alder‐Ene Reaction of Phosphole Sulfides
Authors: Geng Dingjin , Ma Aoyang , Dong Zhenhua , Chai Jinkui
Published: December 2024

We have developed a simple, metal‐free annulation of phosphole sulfides through intramolecular Alder‐ene reaction involving a 1,6‐enyne component. This atom‐efficient cyclization pathway provides phospholene fused polycycles with high yields and excellent regioselectivity. The 1,6‐enyne cyclization of phosphole sulfides with a phenyl group affords structurally complex benzo‐fused bicyclo[3.3.0] scaffolds. Meanwhile, phosphole sulfides with a naphthyl group produce naphtho‐fused bicyclo[4.3.0] skeletons, as well as structurally complex [2+2] cycloaddition products.