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Rattling effect mechanism on the temperature stability of low-sintered Ca 1– x (Li 1/2 Eu 1/2 ) x WO 4 microwave dielectric ceramics for dielectric resonant antenna applications

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Journal of Materiomics 2025年

作者： Qingfeng Li Jie Li Ying Tang Huaicheng Xiang Di Zhou Kaixin Song Liang fang Guangxi Universities Key Laboratory of Non-ferrous Metal Oxide Electronic Functional Materials and Devices College of Materials Science and Engineering Guilin University of Technology Guilin 541004 China Key Laboratory of Multifunctional Materials and Structures Ministry of Education School of Electronic Science and Engineering Xi’an Jiaotong University Xi’an 710049 China College of Electronic Information Hangzhou Dianzi University Hangzhou 310018 China

The low dielectric constant ( ε r < 15) is the key to improving the signal transmission speed of microwave communication devices. However, the resonant frequency temperature coefficient ( τ f ) of most low- ε r microwave dielectric ceramics is usually negative. Aiming to modify the large negative τ f of scheelite CaWO 4 and explore the underlying mechanism between the structure and microwave dielectric properties, a series of Ca 1– x (Li 1/2 Eu 1/2 ) x WO 4 ( x = 0.1−1.0) (CLEWO x ) ceramics were prepared at low sintering temperatures (750−875 °C). The ε r increased from 10.46 to 18.55, and the Q × f decreased from 39,032 GHz to 7425 GHz, mainly due to the enhanced rattling effect of Li + . The τ f rapidly increased from negative (–19.91×10 −6 °C −1 ) to abnormally positive (+162.15×10 −6 °C −1 ), influenced by the reduced temperature coefficient of ion polarizability ( τ αm ) caused by the rattling Li + cation. The CLEWO 0.15 sample has good comprehensive performance ( ε r = 12.28, Q×f = 28,027 GHz, and τ f = –0.5×10 −6 °C −1 ) and compatibility with the Ag electrode, showing the potential of LTCC applications. Additionally, a dielectric resonator antenna based on CLEWO 0.15 ceramic was designed with a bandwidth of 254 MHz at 4.504−4.758 GHz and a gain of 4.87 dBi at 4.62 GHz, indicating that CLEWO 0.15 may be a potential candidate for dielectric resonator antennas.

关键词： Scheelite structure Microwave dielectric properties Rattling effect Abnormal positive τ f LTCC Dielectric resonator antenna

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The common homocystinuria-associated P1173L variant of human methionine synthase impairs reductive methylation

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The Journal of biological chemistry 2025年 110366页

作者： Arkajit Guha Ruma Banerjee Department of Biological Chemistry Michigan Medicine University of Michigan Ann Arbor MI 48109. Department of Biological Chemistry Michigan Medicine University of Michigan Ann Arbor MI 48109. Electronic address: rbanerje@umich.edu.

Human methionine synthase (MTR) is a cobalamin-dependent enzyme, which catalyzes the transfer of a methyl group from methyltetrahydrofolate to homocysteine to form methionine and tetrahydrofolate. The enzyme is susceptible to oxidative inactivation and is repaired by methionine synthase reductase (MTRR) in the presence of NADPH and S-adenosylmethionine (AdoMet). The P1173L missense mutation is the most common clinical variant of MTR and causes homocystinuria, an inborn error of metabolism that is associated with aggressive occlusive cardiovascular diseases. In this study, we report that co-expression of MTR with the B chaperone MMADHC, helps overcome prior challenges with soluble expression of full-length human MTR. Kinetic analysis reveals that wild-type and P1173L MTR exhibit comparable specific activities in the in vitro assay with an artificial reducing system although the K for AdoMet is ∼40-fold higher for the variant. In contrast, the P1173L variant is ∼30 fold less active in the presence of the physiologically relevant MTRR/NADPH reducing system. EPR and kinetic analyses reveal that complex formation with MTRR, which limits the reactivation reaction in wild-type MTR, is unaffected in P1173L MTR, pointing to a switch in the rate-limiting step. Pre-steady state kinetic studies reveal pleiotropic impacts of the P1173L mutation, with electron transfer from MTRR to cob(II)alamin being rate-liming. Our study predicts that physiologically relevant small molecule electron donors, some of which have been tested in this study, might have therapeutic potential to circumvent the penalties associated with P1173L MTR.

关键词： AdoMet S-adenosylmethionine CH 3 -H 4 f methyltetrahydrofolate H 2 OCbl aquocobalamin MeCbl methylcobalamin MTR methionine synthase MTRR methionine synthase reductase MTRR hq hydroquinone form of methionine synthase reductase MTRR sq semiquinone form of methionine synthase reductase

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Tailoring microwave dielectric properties of MgAl 5/4 (Li 1/3 Ti 2/3 ) 3/4 O 4 ceramics for multi-band dielectric resonant antenna

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Journal of Materiomics 2025年第6期11卷

作者： Zhicong Chen Qianbiao Du Guo Tian Linzhao Ma Longxiang Jiang Chang Jiang Zeyan Zhou Hao Li College of Electrical and Information Engineering Hunan University Changsha 410082 China College of Materials Science and Engineering Hunan University Changsha 410082 China

This study introduces a novel microwave dielectric ceramic, MgAl 5/4 (Li 1/3 Ti 2/3 ) 3/4 O 4 , tailored for modern communication technologies. MgAl 5/4 (Li 1/3 Ti 2/3 ) 3/4 O 4 ceramics feature a composite spinel structure ( fd -3m space group) comprising MgAl 2 O 4 and Li 4 Ti 5 O 12 type phases. By substituting Al 3+ of MgAl 2 O 4 ceramic with the composite ion (Li 1/3 Ti 2/3 ) 3+ , differences in elemental diffusion induced by sintering temperature (1200–1280 °C) significantly affect the microwave dielectric properties: a low ε ᵣ (11.83) and enhanced microwave properties ( Q × f = 79,381 GHz and τ f = −28.5 × 10 −6 /°C) at 1240 °C. With further optimization of the ceramics, a near-zero τ f is realized in 0.93MgAl 5/4 (Li 1/3 Ti 2/3 ) 3/4 O 4 -0.07CaTiO 3 ceramics with excellent comprehensive performance ( ε r = 14.36, Q × f = 44,144 GHz). Building on this, a multi-band dielectric resonant antenna (DRA) was designed for applications in communication and aeronautical radio navigation, featuring a wide relative bandwidth of 39.37% (5.97–6.49 GHz and 7.19–9.83 GHz). This study presents an optimization strategy for obtaining microwave dielectric ceramics with low ε r , high Q × f , excellent frequency-temperature stability, low sintering temperature, and low density.

关键词： Microwave dielectric ceramics Near-zero τ f Multi-band dielectric resonant antenna Wide bandwith

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Cholangioscopy-assisted rendezvous endoscopic retrograde cholangiography technique for a difficult postliver transplant anastomotic stricture

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VideoGIE 2025年

作者： Singh, Pankaj Singla, Vikas Goel, Akash Shawl, Muzaffar Rashid Bashir, Shahnawaz Institute of Gastroenterology Hepatology and Endoscopy Max Superspeciality Hospital New Delhi India

Background and Aims: In cases of postliver transplant biliary stricture with double duct anastomsis, double-duct stenting is absolutely necessary to preserve graft function. Methods: We present a successful technique of percutaneous cholangioscopy-assisted rendezvous ERC for difficult anastomotic stricture after failure of cholangioscopy-guided wire negotiation and percutaneous transhepatic biliary drainage. Results: We achieved successful completion of biliary drainage through right anterior sectoral duct and right posterior duct stenting with subsequent dilatation of stricture. There was resolution of anastomotic stricture on follow-up. Conclusions: Cholangioscopy-assisted rendezvous endoscopic retrograde cholangiography technique is a reasonable option for difficult posttransplant anastomotic stricture when conventional methods fail. © 2025 American Society for Gastrointestinal Endoscopy

关键词： PTBD Percutaneous transhepatic biliary drainage RPSD Right Posterior sectoral Duct RASD Right Anterior sectoral Duct PTC Percutaneous transhepatic cholangiogram IHD Intrahepatic Ducts f french

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Evaluation of dose linearity in the systemic availability and pharmacokinetics of topically administered diclofenac: A 14 C-microdosing study in healthy volunteers

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Drug Metabolism and Disposition 2025年第7期53卷

作者： Severin Mairinger Mihye Kwon Martin Bauer Jinho Song Edith Lackner Anselm Jorda felix Bergmann Iris K. Minichmayr Ka Yeon Kim Min Sun Choi Jae Hoon Shim Stephen R. Dueker Markus Zeitlinger Oliver Langer Department of Clinical Pharmacology Medical University of Vienna Vienna Austria Department of Biomedical Imaging and Image-Guided Therapy Medical University of Vienna Vienna Austria Korea Radio-Isotope Center for Pharmaceuticals Korea Institute of Radiological & Medical Sciences Seoul Republic of Korea

An important safety consideration for topically administered drugs is the extent of systemic exposure they achieve. The aim of this study was to evaluate whether a topically administered microdose of the model drug diclofenac can predict the systemic availability, plasma, and tissue pharmacokinetics of a topical therapeutic dose. Eight healthy participants (6 men and 2 women) participated in a 4-period, crossover study. In period 1, a topical microdose (62 ± 6 μ g) was administered; in period 2, a single intravenous microdose (0.95 ± 0.03 μ g) was administered; in period 3, a topical therapeutic dose (120 mg) was administered; and in period 4, a single intravenous therapeutic dose (75 mg) of [ 14 C]diclofenac was administered, with or without the addition of unlabeled diclofenac. Venous blood, urine, and microdialysis samples from subcutaneous adipose tissue beneath the dermal application site were collected for 24 h post-dosing. Total 14 C-concentrations in plasma and microdialysates were quantified using accelerator mass spectrometry. The disposition of intravenously administered [ 14 C]diclofenac was dose-linear. However, after topical administration, the fraction of total 14 C absorbed (geometric mean and 95% confidence interval) was higher ( P = .0019, 2-tailed, paired t test) for the microdose (0.48% and 0.34%–0.67%) compared with the therapeutic dose (0.13% and 0.07%–0.22%) (geometric mean ratio and 90% confidence interval: 3.79 and 2.41–5.98). Dose-normalized 14 C-concentrations in microdialysates were low, variable, and did not differ between doses. Our study demonstrates the feasibility of quantifying 14 C-concentrations in plasma and microdialysates following the topical administration of a microdose of [ 14 C]diclofenac. The observed nonlinearity in systemic availability after topical dosing suggests that microdosing may not accurately predict the disposition of certain topical drugs at therapeutic doses. Significance Statement We assessed whether a topi

关键词： Dose linearity Microdialysis Microdosing Topical drugs AUC 0–24 area under the concentration-time curve from 0 to 24 h AUC 0-inf area under the concentration-time curve from 0 to infinity AMS accelerator mass spectrometry 14 C carbon-14 f abs fraction absorbed GMR geometric mean ratio HSA human serum albumin LC-MS/MS liquid chromatography tandem mass spectrometry LLOQ lower limit of quantification LSC liquid scintillation counting ng-eg/mL nanogram diclofenac equivalents per milliliter PK pharmacokinetic(s)

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Practical Approach toward gem-Difluorinated Ring Expansion of Exocyclic Alkenes

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Synfacts 2025年第4期21卷 413-413页

作者： Antonia f. Stepan Seong Heon Kim

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Performance evaluation of geopolymer masonry units: A hybrid approach combining laboratory testing and AI modeling

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Case Studies in Construction Materials 2025年 23卷

作者： Md. Zia Ul Haq Sandeep Singh Tarak Vora A.K. Dasarathy Kaushik Bharti Vanitha S Priyadarshi Das Laura Ricciotti Centre for Research Impact and Outcome Chitkara University Institute of Engineering and Technology Chitkara University Rajpura Punjab 140401 India Department of Civil Engineering School of Engineering and Technology Bahra University Waknaghat Distt Solan Himachal Pradesh India Faculty of Engineering Sohar University Sohar Oman Marwadi University Research Center Department of Civil Engineering Faculty of Engineering & Technology Marwadi University Rajkot Gujarat India Professor Department of Civil Engineering School of Engineering and Technology JAIN (Deemed to be University) Bangalore Karnataka India Department of Civil Engineering Chandigarh Engineering College Chandigarh Group of Colleges-Jhanjeri Mohali Punjab 140307 India Department of Civil Engineering Sathyabama Institute of Science and Technology Chennai Tamil Nadu India Department of Civil Engineering Siksha 'O' Anusandhan (Deemed to be University) Bhubaneswar Odisha 751030 India Department of Architecture and Industrial Design University of Campania Luigi Vanvitelli via San Lorenzo Aversa 81031 Italy

This study presents a comprehensive investigation into the compressive strength and stress–strain behavior of geopolymer brick masonry, focusing on both prisms and wallettes. Geopolymer bricks and mortars were used to fabricate specimens, and their mechanical performance was experimentally evaluated. The study also employs nine machine learning algorithms on a dataset comprising 612 prism and 63 wallette data points, assessing performance based on six predictive metrics. Experimental results revealed that prisms exhibited higher compressive strength (7.2 MPa to 2.6 MPa) compared to wallettes (6.5 MPa to 1.2 MPa), with a linear regression indicating wallettes achieve approximately 88 % of prism strength. Among the ML models, Random forest performed best, with R² values of 0.92 and 0.97 for prism and wallette datasets, respectively. The results emphasize the influence of brick-and-mortar properties and dimensional parameters on masonry performance. This study advances the understanding of geopolymer masonry and demonstrates the synergy of experimental analysis and machine learning for predictive modeling in sustainable construction.

关键词： L [m] Length of the masonry unit B [m] Width of the masonry unit H [m] Height of the masonry unit T [m] Mortar thickness H P [m] Height of the masonry prism H P [m] Height of the masonry Wallette’s f b [MPa] Compressive strength masonry unit f m [MPa] Compressive strength mortar f MP [MPa] Compressive strength masonry prism fMW [MPa] Compressive strength masonry Wallette’s MSE Mean Squared Error R² R-squared MAE Mean Absolute Error MedAE Median Absolute Error EVS Explained Variance Score RMSE Root Mean Squared Error Geopolymer bricks Masonry performance Machine learning Prism Wallettes Dimensional parameters

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Long-Term Efficacy of Dupilumab in Moderate-to-Severe Asthma Phenotyped by Blood Eosinophils and Exhaled Nitric Oxide

CHEST Pulmonary

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CHEST Pulmonary 2025年第1期3卷 100072-100072页

作者： Michael E. Wechsler Ian D. Pavord Alberto Papi Kenneth R. Chapman Arman Altincatal Nami Pandit-Abid Juby A. Jacob-Nara Paul J. Rowe Yamo Deniz Elizabeth Laws Bolanle Akinlade Nikhil Amin Heribert W. Staudinger David J. Lederer Megan Hardin Division of Pulmonary Critical Care and Sleep Medicine National Jewish Health Denver CO NIHR Oxford Biomedical Research Centre University of Oxford Oxford England Respiratory Medicine Unit University of Ferrara S. Anna University Hospital Ferrara Italy University of Toronto Toronto ON Canada Sanofi Cambridge MA Sanofi Bridgewater NJ Regeneron Pharmaceuticals Inc. Tarrytown NY

Background Asthma treatment aims to reduce symptom severity and exacerbation risk. Dupilumab, a human monoclonal antibody, blocks the shared receptor for IL-4/IL-13, key drivers of type 2 inflammation. In the Evaluation of Dupilumab in Patients With Persistent Asthma (QUEST) study (NCT02414854), add-on dupilumab every 2 weeks vs placebo was shown to significantly reduce severe asthma exacerbations and improve prebronchodilator (BD) fEV 1 in patients with uncontrolled, moderate-to-severe asthma. Treatment effects were greater in patients with elevated baseline type 2 biomarkers (blood eosinophil count ≥ 150 cells/μL or fractional exhaled nitric oxide ≥ 25 parts per billion). Research Question What is dupilumab’s long-term efficacy (up to 3 years) in patients with moderate-to-severe type 2 asthma? Study Design and Methods Patients enrolled in QUEST (receiving placebo or dupilumab), who completed 96 weeks of dupilumab treatment in the open-label extension Long-Term Safety Evaluation of Dupilumab in Patients With Asthma (TRAVERSE) study (NCT02134028), were included. This prespecified analysis evaluated long-term efficacy in patient populations identified by baseline type 2 biomarker level. End points were annualized exacerbation rate (AER) and change from baseline in pre-BD fEV 1 (L), asthma control (5-item Asthma Control Questionnaire), and asthma-related quality of life (Asthma Quality of Life Questionnaire). Results A total of 663 patients were included. AER was 1.72 to 2.24 at QUEST baseline in dupilumab groups across type 2 populations. AER decreased in populations with elevated type 2 biomarkers to 0.36 to 0.49 during QUEST’s 52-week treatment period, which was sustained over 96 weeks in TRAVERSE. In patients with low type 2 biomarker levels, there was no clinically meaningful AER reduction in QUEST or TRAVERSE, but rates remained below parent study baseline. Similar trends were seen with improvements in pre-BD fEV 1 , 5-item Asthma Control Questionnaire, and Asth

关键词： asthma biomarkers dupilumab eosinophil count fractional exhaled nitric oxide ACQ-5 5-item Asthma Control Questionnaire AER annualized exacerbation rate AQLQ Asthma Quality of Life Questionnaire BD bronchodilator f eno fractional exhaled nitric oxide ppb parts per billion PSBL parent study baseline

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着丝粒蛋白f在肝癌中的表达和对肝癌细胞生物学行为的影响

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临床和实验医学杂志 2018年第19期17卷 2017-2021页

作者：李潇瑾徐安健周东虎张蓓黄坚首都医科大学附属北京友谊医院科研实验中心北京市临床医学研究所北京100050

目的探讨肝癌中着丝粒蛋白f(CENPf)的表达量与细胞增殖、迁移等生物学行为的关系及其作用机制。方法比较肝癌细胞与正常肝细胞、肝癌组织与癌旁正常组织中CENPf的表达量。利用慢病毒包被的质粒转染肝癌细胞干扰CENPf的表达,分别使用MTS... 详细信息

目的探讨肝癌中着丝粒蛋白f(CENPf)的表达量与细胞增殖、迁移等生物学行为的关系及其作用机制。方法比较肝癌细胞与正常肝细胞、肝癌组织与癌旁正常组织中CENPf的表达量。利用慢病毒包被的质粒转染肝癌细胞干扰CENPf的表达,分别使用MTS试剂、台盼兰染色法、transwell迁移小室方法研究CENPf的表达对细胞增殖、存活、迁移的影响,并利用Western blotting法探究其对细胞周期调控蛋白c-Myc、Cyclin D1表达的影响,明确CENPf作用机制。结果与正常肝细胞和癌旁正常组织相比,肝癌细胞和肝癌组织中CENPf蛋白表达量显著增加。使用病毒包被的质粒抑制CENPf的表达可显著降低肝癌细胞的增殖能力、存活率和迁移能力,同时调控细胞增殖和细胞周期的蛋白(c-Myc、Cyclin D1)的表达降低。结论肝癌中过表达的CENPf可通过激活细胞周期调控蛋白c-Myc和Cyclin D1,提高肝癌细胞的增殖、存活、迁移能力,诱导肝癌的发生和发展。

关键词：肝癌着丝粒蛋白 f 细胞周期细胞性骨髓瘤病毒癌基因蛋白细胞周期蛋白 D1

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A comprehensive analysis of coal toughness index: Relationships among coal toughness index, uniaxial compressive strength and proximity parameters

Journal of Industrial Safety

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Journal of Industrial Safety 2024年第2期1卷

作者： Itmam Abedin Ting Ren Zhongbei Li Ming Qiao Xueqiu He Jessica Juric School of Civil Mining Environmental and Architectural Engineering University of Wollongong Wollongong NSW 2522 Australia School of Civil and Resource Engineering University of Science and Technology Beijing Beijing 10083 China South32 – Illawarra Metallurgical Coal Wollongong NSW 2526 Australia

Coal and gas outbursts are significant safety hazards in underground coal mining, particularly in deep Australian coal seams. While the traditional outburst risk management relies on threshold limit values of seam gas content, recent experiences have shown that this approach overlooks important factors such as coal toughness and strength. This study evaluates the effectiveness of the coal toughness test, also known as the Protodyakonov strength test, as a predictor of outburst risk. After upgrading the test rig and updating testing procedures, the toughness index f was compared with conventional strength parameters, revealing a strong positive correlation with uniaxial compressive strength (UCS) and drop hammer impact strength. An analysis of 98 coal samples taken from seven seams at three Australian mines revealed that lower moisture content and higher apparent relative density are associated with increased coal toughness. Specifically, the Pearson and Spearman correlation coefficients of −0.79 and −0.78 were observed, respectively, indicated a strong negative relationship between coal moisture content and toughness. Additionally, coal seams with lower volatile matter content exhibited higher toughness values. The study proposes adopting the coal toughness index as a robust alternative to the conventional indicators such as UCS, especially when obtaining intact coal samples is difficult. Incorporating the toughness index into the outburst risk assessment can improve safety by adopting a more comprehensive and reliable approach.

关键词： Coal and gas outburst Coal toughness index f Coal strength Proximity parameters Outburst risk assessment

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