bluuebunny/crossref_metadata_2025_split huggingface dataset:
Axial Ligand Enables Synthesis of Allenylsilane through Dirhodium(II) Catalysis
Authors: Li Wendeng , Wu Rui , Ruan Hao , Xiao Bo , Gao Xiang , Jiang Huanfeng , Chen Kai , Sun Tian‐Yu , Zhu Shifa 
Published: June 2024

AbstractDescribed herein is a dirhodium(II)‐catalyzed silylation of propargyl esters with hydrosilanes, using tertiary amines as axial ligands. By adopting this strategy, a range of versatile and useful allenylsilanes can be achieved with good yields. This reaction not only represents a SN2′‐type silylation of the propargyl derivatives bearing a terminal alkyne moiety to synthesize allenylsilanes from simple hydrosilanes, but also represents a new application of dirhodium(II) complexes in catalytic transformation of carbon‐carbon triple bond. The highly functionalized allenylsilanes that are produced can be transformed into a series of synthetically useful organic molecules. In this reaction, an intriguing ON‐OFF effect of the amine ligand was observed. The reaction almost did not occur (OFF) without addition of Lewis base amine ligand. However, the reaction took place smoothly (ON) after addition of only catalytic amount of amine ligand. Detailed mechanistic studies and density functional theory (DFT) calculations indicate that the reactivity can be delicately improved by the use of tertiary amine. The fine‐tuning effect of the tertiary amine is crucial in the formation of the Rh−Si species via a concerted metalation deprotonation (CMD) mechanism and facilitating β‐oxygen elimination.
Maximum weighted correntropy filters for nonlinear non‐Gaussian systems
Authors: Liu Jingang , Zhang Wenbo , Song Shenmin 
Published: June 2024

AbstractIn this paper, we focus on the filtering issue for nonlinear non‐Gaussian systems. Considering the limitations of the Gaussian function with a single kernel bandwidth, we design a novel extended version called weighted Gaussian function, which consists of a weighting coefficient and two distinct kernel bandwidths. The additional coefficient can directly balance two kernel bandwidths, which improves the flexibility and performance of the correntropy. We develop a cost function utilizing the suggested weighted Gaussian function and statistical linearization method, followed by deriving a maximum weighted correntropy filter based on the maximum correntropy criterion. The proposed algorithm is demonstrated to converge to a Gaussian filter as the kernel bandwidths approach infinity. In addition, we derive the corresponding information filter, which takes the form of information matrix and information vector. It is computationally efficient and easier to generalize to multisensor systems. The performance of the proposed algorithms is compared with other filters based on the third‐order spherical cubature rule and the fixed point iteration technique in a target tracking system. Simulation results confirm the effectiveness of the new approaches.
Novel Caputo fractional differential approach and hybrid control scheme for finite‐time synchronization of nonidentical delayed reaction–diffusion neural networks
Authors: Zhang Hai , Wang Chen , Ye Renyu , Cao Jinde 
Published: June 2024

AbstractThis work focuses on the finite‐time synchronization (F‐TS) for nonidentical delayed neural networks (DNNs) including Caputo fractional partial differential operator and reaction–diffusion terms. A novel F‐TS lemma is proposed by constructing a new Caputo differential inequality. Applying the new lemma and designing two hybrid controllers with time delay and the sign function, the F‐TS criteria on the introduced Caputo reaction–diffusion nonidentical DNNs under the Neumann boundary condition are derived by making use of the Filippov differential inclusion, Green's theorem, and fractional Razumikhin theorem. The conditions are expressed through the algebraic inequality which can greatly decrease the computation in checking the F‐TS performance. Moreover, the validity and correctness of the F‐TS results are illustrated by selecting various orders, spatial positions, and diffusion parameters.
Adaptive fuzzy tracking control for multiple‐input multiple‐output nonlinear systems with sensor faults and experiment in the flexible‐joint robot
Authors: Yuan Junhao , Sun Wei 
Published: June 2024

AbstractThis paper is centered on the adaptive asymptotic tracking control of multi‐input multi‐output uncertain strict‐feedback nonlinear systems in the presence of both multiplicative and additive sensor faults. Through adaptive accommodation techniques, the proposed control scheme can dynamically compensate for sensor faults, thereby ensuring precise and stable control. The control scheme is devised using the backstepping design that incorporates positive integrable time‐varying functions, thereby ensuring the boundedness of all signals in the closed‐loop system and guaranteeing that the output tracking error asymptotically converges to zero. Additionally, extensive simulations and experimental evaluations conducted on the Quanser platform with 2‐link flexible‐joint robots demonstrate the efficacy of the proposed control scheme in mitigating the impact of sensor faults and achieving accurate tracking performance.
Identifying barriers and good practices for implementing circular economy principles in small and medium enterprises
Authors: Palombi Giulia , Schiaroli Valerio , Fraccascia Luca , Nonino Fabio 
Published: June 2024

AbstractRecently, the new industrial paradigm of circular economy (CE) has acquired increasing attention. In a CE, the value of materials is preserved by keeping them for as long as possible in the economic system, overcoming the “traditional” linear model (take‐waste‐disposal). Despite its benefits in terms of sustainability, there are still numerous barriers to the implementation of CE principles for companies, and specifically, small and medium enterprises (SMEs) find it difficult to integrate CE principles within their business models due to a shortage of resources. Hence, a qualitative multiple‐case study involving four Italian companies implementing CE principles is conducted. The findings contribute to the development of CE principles in SMEs by proposing good practices, such as encouraging SMEs to engage in research projects to secure initial investments, expanding suppliers' networks to reduce the risk of limited by‐product availability, and implementing organizational training on CE to enhance employees' awareness and skills.
PD‐1 blockade enhances the effect of targeted chemotherapy on locally advanced pMMR/MSS colorectal cancer
Authors: Pei Fengyun , He Wan , Duan Yinghua , Yao Qijun , Zhao Yandong , Fan Xinjuan , Liu Shuai , Chen Haiyang , He Fang , Liu Tingzhi , Chen Jiaoting , Zheng Yijia , Li Heping , Guo Xiaofang , Shi Lishuo , Ling Li , Chen Yaoxu , He Jiapeng , Liu Miao , Huang Mengli , Bai Yuezong , Wang Jianping , Huang Meijin , Huang Jun 
Published: June 2024

AbstractBackgroundPatients with DNA mismatch repair‐proficient/microsatellite stable (pMMR/MSS) colorectal cancer (CRC), which accounts for 85% of all CRC cases, display a poor respond to immune checkpoint inhibitors (i.e., anti‐PD‐1 antibodies). pMMR/MSS CRC patients with locally advanced cancers need effective combined therapies.MethodsIn this pilot study, we administered six preoperative doses of each 2‐week cycle of the anti‐PD‐1 antibody sintilimab (at a fixed dose of 200 mg), oxaliplatin, and 5‐FU/CF (mFOLFOX6) combined with five doses of bevacizumab (the number of doses was reduced to prevent surgical delays) to patients with cT4NxM0 colon or upper rectal cancers. And radical surgery was performed approximately 2 weeks after the last dose of neoadjuvant therapy. The primary endpoint was a pathologic complete response (pCR). We also evaluated major pathologic response (MPR, ≤10% residual viable tumor), radiological and pathological regression, safety, and tumor mutation burden (TMB), and tumor microenvironment (TME) characteristics.ResultsBy the cutoff date (September 2023), 22 patients with cT4NxM0 pMMR/MSS colon or upper rectal cancers were enrolled and the median follow‐up was 24.7 months (IQR: 21.1–26.1). All patients underwent R0 surgical resection without treatment‐related surgical delays. pCR occurred in 12 of 22 resected tumors (54.5%) and MPR occurred in 18 of 22 (81.8%) patients. At the cutoff date, all patients were alive, and 21/22 were recurrence‐free. Treatment‐related adverse events of grade 3 or higher occurred in of 2/22 (9.1%) patients. Among the pCR tumors, two were found to harbor POLE mutations. The degree of pathological regression was significantly greater than that of radiological regression (p = 1.35 × 10−8). The number of CD3+/CD4+ cells in the tumor and stroma in pretreated biopsied tissues was markedly lower in pCR tumors than in non‐pCR tumors (p = 0.038 and p = 0.015, respectively).ConclusionsNeoadjuvant sintilimab combined with bevacizumab and mFOLFOX6 was associated with few side effects, did not delay surgery, and led to pCR and non‐pCR in 54.5% and 81.8% of the cases, respectively. Downregulation of CD3/CD4 expression in the tumor and stroma is related to pCR. However, the molecular mechanisms underlying PD‐1 blockade‐enhanced targeted chemotherapy require further investigation.
Structures and Protein Engineering of the α‐Keto Acid C‐Methyltransferases SgvM and MrsA for Rational Substrate Transfer
Authors: Sommer‐Kamann Christina , Breiltgens Juliane , Zou Ziruo , Gerhardt Stefan , Saleem‐Batcha Raspudin , Kemper Florian , Einsle Oliver , Andexer Jennifer N. , Müller Michael 
Published: June 2024

AbstractS‐adenosyl‐l‐methionine‐dependent methyltransferases (MTs) are involved in the C‐methylation of a variety of natural products. The MTs SgvM from Streptomyces griseoviridis and MrsA from Pseudomonas syringae pv. syringae catalyze the methylation of the β‐carbon atom of α‐keto acids in the biosynthesis of the antibiotic natural products viridogrisein and 3‐methylarginine, respectively. MrsA shows high substrate selectivity for 5‐guanidino‐2‐oxovalerate, while other α‐keto acids, such as the SgvM substrates 4‐methyl‐2‐oxovalerate, 2‐oxovalerate, and phenylpyruvate, are not accepted. Here we report the crystal structures of SgvM and MrsA in the apo form and bound with substrate or S‐adenosyl‐l‐methionine. By investigating key residues for substrate recognition in the active sites of both enzymes and engineering MrsA by site‐directed mutagenesis, the substrate range of MrsA was extended to accept α‐keto acid substrates of SgvM with uncharged and lipophilic β‐residues. Our results showcase the transfer of the substrate scope of α‐keto acid MTs from different biosynthetic pathways by rational design.
Diffuse large B‐cell lymphoma‐induced intussusception: A case report and literature review
Authors: Chang Hao‐Cheng , Kang Jung‐Cheng , Pu Ta‐Wei , Su Ruei‐Yu , Chen Chao‐Young , Hu Je‐Ming 
Published: June 2024

Key Clinical MessageAdult intussusception necessitates early surgical intervention. We emphasis the significance of considering diffuse large B‐Cell lymphoma in differential diagnoses for adult intussusception, particularly in the colon, to ensure precise diagnosis and optimal management.
Re‐Examination of Self‐Decay Chemistry of Phthalimide‐N‐oxyl Redox‐Organocatalyst for Free‐Radical CH‐Functionalization – Puzzle Begins to Come Together
Authors: Lopat'eva Elena R. , Krylov Igor B. , Subbotina Irina R. , Nikishin Gennady I. , Terent'ev Alexander O. 
Published: June 2024

AbstractPhthalimide‐N‐oxyl radicals (PINO) are catalytically active hydrogen abstracting species generated from N‐hydroxyphthalimide (NHPI) – one of the most efficient and widely used organocatalysts for free‐radical oxidative CH‐functionalization processes. The self‐decay of PINO is one of the main limiting factors of NHPI usage, but currently there is no consensus on the mechanism of this important process. In the present work, quantitative EPR and NMR monitoring of PINO generation and degradation along with decay product analysis and control experiments allowed us to build a consistent picture of PINO decay chemistry and put together previously contradictory results. PINO yields achievable employing various oxidants were measured and compared for the first time. At least two PINO decay pathways were revealed: “trimerization” (with partial fragmentation, favored by high PINO concentrations at initial stage of decay), and medium oxidation favored by low PINO concentrations. The main PINO decomposition product, the “trimer” can easily be recycled back to NHPI.
Atomistic Insights Into the Surface Dynamics of Ni(111) During Reverse Water gas Shift Reaction
Authors: David Roey Ben , Andres Miguel A. , Shalom Bat‐Or , Karagoz Burcu , Held Georg , Eren Baran 
Published: June 2024

AbstractThe conversion of CO2‐H2 mixtures on Ni‐based catalysts can proceed through either the reverse water gas shift reaction (RWGS) path to produce CO or the CO2 methanation path to produce CH4. The balance between these competing reactions depends on both the reaction conditions and catalyst structure. In this study, using surface‐sensitive infrared and ambient pressure X‐ray photoelectron spectroscopies, we investigate the effect of reaction conditions on the interaction between CO2 and H2 on a Ni(111) model catalyst. Our findings highlight the occurrence of RWGS, involving direct dissociation of CO2 to CO and atomic oxygen, followed by oxygen reacting with hydrogen to form H2O, and CO and H2O desorption. Hydrogen affects the distribution of CO between hollow and top sites by displacing oxygen from the energetically preferred hollow sites. The overall balance between oxygen production from CO2 dissociation and oxygen removal by hydrogen governs the oxygen coverage and consequently the distribution of CO between top and hollow sites. This balance is significantly influenced by the reaction temperature and the H2/CO2 partial pressures.
Enhancing Secondary Alkaline Battery Performance: Synthesis and Electrochemical Characterization of Zn Anodes, Based on ZnO@C Core‐Shell Nanoparticles
Authors: Emanuele Elisa , Li Bassi Andrea , Macrelli Andrea , Magagnin Luca , Bozzini Benedetto 
Published: June 2024

AbstractWhile alkaline Zn batteries, like traditional rechargeable aqueous batteries, boast an advantage in terms of energy density, their progress has been hampered by concerns related to the anode. These concerns include issues like Zn dendrites, self‐corrosion, passivation, shape change, and the hydrogen evolution reaction (HER). To tackle these challenges, we have introduced a nanostructuring approach for the anode, employing carbon‐coated ZnO nanoparticles (ZnO@C) as the active material. In this study, we synthesized ZnO@C nanoparticles in an environmentally sustainable and scalable manner to address passivation and dissolution issues jointly. Nanoscale ZnO particles effectively prevent passivation, while carbon shell slows down the dissolution of zincate. The Zn anode exhibits a significant performance boost when compared to Zn foil and bare ZnO nanoparticles, even when subjected to demanding conditions (without the use of ZnO‐saturated electrolyte). This rechargeable Zn anode marks a significant step toward the realization of practical, high‐energy rechargeable aqueous batteries, such as Zn‐air batteries.
Moving Down Group 1: Analytical Challenges and Current Trends for Solid Polymer Electrolytes in Post‐Li Battery Applications
Authors: Jeschull Fabian 
Published: June 2024

AbstractThe solid polymer electrolyte (SPE) field has traditionally struggled with sufficiently high cation conduction at room temperature. The reason for this is that ion transport is usually coupled to polymer chain mobility and as such is strongly temperature dependent. The diversification of battery technologies from Li‐ion into Na‐ and K‐ion batteries has revived efforts in the 80s and 90s to develop a broad conceptional understanding and to find overarching trends of the ion transport properties of SPEs based on Group 1 elements, Li+, Na+, K+, Rb+ and Cs+ (i. e. beyond Li). This development brings its own set of challenges, starting from additional constraints to measure heavier cations. With a clearer aim towards tangible battery applications, particularly electrochemical stability and interphase formation, and together with a rising sensibility of sustainability aspects, other parameters have gained more relevance and opened new vectors of research. The associated scientific challenges and recent developments of Group 1 based SPEs shall be reviewed.
Pyridinethiolate‐Capped CdSe Quantum Dots for Red‐Light‐Driven H2 Production in Water
Authors: Wei Zuting , Yang Shuang , Lei Jingxiang , Guo Kai , Yuan Huiqing , Ming Mei , Du Jiehao , Han Zhiji 
Published: June 2024

AbstractThe utilization of low‐energy sunlight to produce renewable fuels is a subject of great interest. Here we report the first example of metal chalcogenide quantum dots (QDs) capped with a pyridinethiolate carboxylic acid (pyS‐COOH) for red‐light‐driven H2 production in water. The precious‐metal‐free system is robust over 240 h, and achieves a turnover number (TON) of 43910±305 (vs Ni) with a rate of 31570±1690 μmol g−1 h−1 for hydrogen production. In contrast to the inactive QDs capped with other thiolate ligands, the CdSe‐pyS‐COOH QDs give a significantly higher singlet oxygen quantum yield [ΦΔ (1O2)] in solution.
An In‐Depth Exploration of Six Decades of the Kröhnke Pyridine Synthesis
Authors: Francisco Telmo N. , Albuquerque Hélio M. T. , Silva Artur M. S. 
Published: June 2024

AbstractThe Kröhnke Pyridine Synthesis has been discovered about six decades ago (1961), by Fritz Kröhnke and Wilfried Zecher at the University of Giessen. The original method involved the reaction of α‐pyridinium methyl ketone salts with α,β‐unsaturated carbonyl compounds in the presence of a nitrogen source, frequently ammonium acetate. Since its discovery, the Kröhnke methodology has been demonstrated to be suitable for the preparation of mono‐, di‐, tri‐ and tetra‐pyridines, with important applications in several research fields. Over the years, a number of modifications to the original approach have been developed and reported, enabling for the broad applicability of these methods even in modern days, also for the synthesis of non‐pyridine compounds. In this critical and tutorial review, we will thoroughly explore and discuss the potential of the original method, the refinements that have been made over the years, as well as some applications arising from each type of pyridine and/or non‐pyridine compounds produced by Kröhnke's approach.
Effect of Rare Earth Ion Substitution on Phase Decomposition of Apatite Structure
Authors: Sharma Geeta , Loganathan Sarathkumar , Barimah Eric K. , Georgopoulou Paraskevi , Taylor Esther , Scott Andrew J. , Strafford Simon , Jha Animesh 
Published: June 2024

AbstractThe paper describes an investigation of phase decomposition of apatite lattice doped with rare earth ions (cerium, samarium, and holmium) at temperatures ranging from 25–1200 °C. The rare‐earth ion‐doped apatite minerals were synthesized using the sol‐gel method. In situ high‐temperature powder X‐ray diffraction (XRD) was used to observe the phase changes and the lattice parameters were analyzed to ascertain the crystallographic transformations. The expansion coefficient of the compounds was determined, and it was found that the c‐axis was the most expandable due to relatively weak chemical bonds along the c‐crystallographic axis. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to examine the decomposition properties of the materials. Due to rare earth ion doping, the produced materials had slightly variable decomposition behaviour. The cerium and samarium ions were present in multiple oxidation states (Ce3+, Ce4+, Sm3+, Sm2+), whereas only Ho3+ ions were observed. Rare earth ion substitution affects tri‐calcium phosphate proportion during decomposition by regulating concentrations of vacancies. X‐ray photoelectron spectroscopy (XPS) analysis indicated that cerium and samarium ion‐doped apatite yielded only 25 % tricalcium phosphate during decomposition. This finding advances our understanding of apatite structures, with implications for various high‐temperature processes like calcination, sintering, hydrothermal processing, and plasma spraying.
Trends in genetic gain for yam in the IITA breeding program
Authors: Asfaw Asrat , Agre Paterne A. , Dieng Ibnou , Adebola Patrick , Obidiegwu Jude E. , Chamba Emmanuel , Darkwa Kwabena , Otoo Emmanuel , Dansi Alexandre , Dibi Konan Evrard Brice , Kouakou Amani Michel , Asiedu Robert 
Published: June 2024

AbstractMonitoring genetic gain is crucial to ensure breeding programs' effectiveness and identify potential challenges and areas for their improvement. Our study provides a first overview of the trends in genetic gain for tuber yield and disease resistance traits in the IITA's (International Institute of Tropical Agriculture) yam breeding program. We used historical data (2010–2022) from multiple generations of past breeding cycles evaluated at 31 sites in the white Guinea yam (Dioscorea rotundata Poir) breeding pipeline and 28 sites in the water yam (Dioscorea alata L.) breeding pipeline of IITA and its national partners in West Africa. Our result shows positive genetic trends in fresh tuber yield while recording a gain of 1.38% or 99.17 kg ha−1 per year in the white Guinea yam and 2.18% or 252.41 kg ha−1 per year in the water yam breeding pipelines. Genetic trends for virus and anthracnose resistance were in the desired direction but negligible in white Guinea yam, while significant for virus and nonsignificant for anthracnose resistance in water yam. Our findings indicate that while the breeding program has succeeded in enhancing tuber yield, post‐harvest tuber dry matter content and disease resistance (yam mosaic virus and anthracnose) did not follow a similar trend in the material being developed. This implies that the yam breeding program needs to strike a balance between various traits, ensuring that increased yield does not come at a cost to food quality or disease resistance. Our results highlight the importance of continually monitoring and assessing the performance of a breeding program and making informed decisions about which traits to focus on for future improvement.
Design of a transistor‐based broadband high‐efficiency class‐F−1 rectifier
Authors: Zhang Zhiwei , Gu Chao , Xuan Xuefei , Zhang Luyu , Wang Chenlu 
Published: June 2024

AbstractThis brief proposes an innovational method to design a broadband high‐efficiency transistor‐based rectifier with high rectification efficiency. The theory of the class‐F−1 rectifier with the input second harmonic component is explored. Moreover, the mathematical variations of rectification efficiency and load/source impedances versus several crucial design parameters are established. The variation relationships indicate that the rectification efficiency can roughly maintain constant across a large input second harmonic range, resulting in more available design impedances. Thus, this provides the possibility to design wideband rectifiers. For validation, a broadband high‐efficiency class‐F−1 rectifier (operating in 1.6–2.6 GHz) using a GaN transistor is designed, assembled, and measured. Measurements indicate a rectification efficiency of between 72.1% and 82.4% under the condition of Rdc = 67 Ω and Pin = 40 dBm. The realized rectifier exhibits the largest relative bandwidth compared with transistor‐based rectifiers reported before. The methodology presented in this brief provides a promising approach for broadband high‐efficiency GaN HEMT‐based rectifiers.