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Production and characterization of polymeric nanocomposite foams based on starch and cellulose nanofibers from oil palm mesocarp fiber

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Applied Nanoscience (Switzerland) 2025年第2期15卷 1-11页

作者： Souza, Mariana Costa Gonçalves, Ana Paula Bispo da Silva Oliveira, Emanoel Igor dos Santos, Juscivaldo Passos Lazzari, Lídia Kunz Zattera, Ademir José José, Nadia Mamede Chemical Engineering Graduate Program Polytechnic School Federal University of Bahia Bahia Salvador Brazil Department of Education Federal Institute of Education Science and Technology Feira de Santana Bahia Brazil Postgraduate Program in Process Engineering and Technologies University of Caxias Do Sul Rio Grande Do Sul Caxias Do Sul Brazil

The demand for sustainable and eco-friendly materials has promoted studies over the years to explore different polymeric materials that meet requirements such as biodegradability and sustainability. In this context, biopolymer materials based on cellulose nanoparticles and starch from different botanical sources have been investigated, aiming to achieve satisfactory performance. The present study aims to develop and characterize cassava starch foams based on density, scanning electron microscopy (SEM), and three-point flexure tests, and to evaluate the effect of cellulose nanofibers obtained from palm mesocarp fibers using the ultrafine friction grinding method after different processing times, characterized by X-ray diffractometry (XRD), microscopy, and chemical composition, as a reinforcing filler. The chemical composition and scanning electron microscopy revealed the effectiveness of the cellulose isolation process, with the analysis of the chemical composition revealing a cellulose content of 55.70% in the fibers after pulping and bleaching, in addition to changes in the visual characteristics of the material after the process aimed at isolating the cellulose. After grinding, XRD showed an increase in crystallinity (76.1% at the maximum grinding time), along with typical microscopy images of cellulose nanofibers. The analysis of the obtained nanocomposites provided insights into the role of these nanostructures in the thermo-expanded starch matrix, indicating that the nanofibers promoted changes such as an increase in mechanical properties and crystallinity, which contributed to improving overall mechanical performance. A 67.48% increase in flexural strength was achieved for the formulation with cellulose nanofibers that underwent 150 min of grinding, without causing major variations in density. © King Abdulaziz City for science and technology 2025.

关键词： Starch

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A Design Study on Integrated Complex Coefficient Filters with Peripheral Circuits for Accurate Frequency Response Measurement

IEEJ Transactions on Electronics, Information and Systems

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IEEJ Transactions on Electronics, Information and Systems 2025年第1期145卷 16-24页

作者： Shouno, Kazuhiro Sato, Lina Fukagawa, Kanta Tanimoto, Hiroshi Muto, Cosy Division of Information Engineering University of Tsukuba 1-1-1 Tennoudai Ibaraki Tsukuba305-8573 Japan Graduate School of Science and Technology Degree Programs in Systems and Information Engineering Master’s Program in Computer Science University of Tsukuba Japan Kitami Institute of Technology 165 Koen-cho Hokkaido Kitami090-8507 Japan Faculty of Education Nagasaki University 1-14 Bunkyo-machi Nagasaki852-8521 Japan

This paper proposes a measurement technique for an integrated complex filter. The proposed method is based on two measurement methods with integrated circuitry for calibration. It is accomplished by applying square waves to an FUT (Filter Under Test) instead of sinusoidal waves or by superposing transfer characteristics obtained by applying a single sinusoidal wave to an FUT. In both of the above methods, the output signal connected to the external measurement equipment via a 50 Ω coaxial cable and so on. In this case, the output signal of the FUT should be amplified by internal or external amplifiers, which degrades the response. However, it is cancelled out by the proposed calibration circuitry with some analog switches. In addition to the above, for the RC polyphase filter, the source resistance and the load capacitance degrade the measurement results and their effect is discussed. The validity of the proposal is confirmed through computer simulation for a third-order RCPF whose passband is 8–40 MHz fabricated by Phenitec 0.6 µm CMOS process. It is shown that the measurement error is −1.10 dB for the square-wave method and −1.00 dB and −0.43 degrees for the superposition method at 40 MHz. © 2025 The Institute of Electrical Engineers of Japan.

关键词： Capacitance

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Implementation and Evaluation of 0.6 µm CMOS Complex RCPF for Accurate Frequency Response Measurement

IEEJ Transactions on Electronics, Information and Systems

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IEEJ Transactions on Electronics, Information and Systems 2025年第1期145卷 25-37页

作者： Sato, Lina Fukagawa, Kanta Shouno, Kazuhiro Tanimoto, Hiroshi Muto, Cosy Moriyama, Seijiro Takahashi, Chikau Yoshino, Michitaka Graduate School of Science and Technology Degree Programs in Systems and Information Engineering Master’s Program in Computer Science University of Tsukuba Japan Division of Information Engineering University of Tsukuba 1-1-1 Tennoudai Ibaraki Tsukuba305-8573 Japan Kitami Institute of Technology 165 Koen-cho Hokkaido Kitami090-8507 Japan Faculty of Education Nagasaki University 1-14 Bunkyo-machi Nagasaki852-8521 Japan Anagix Corporation 3-22-27 Numama Kanagawa Zushi249-0004 Japan Takamori Corporation Japan Research Center for Micro-Nano Technology Hosei University 3-11-15 Midori-cho Koganei Tokyo184-0003 Japan

This paper describes the implementation and evaluation of an RC polyphase filter (RCPF) and circuitry for measuring its frequency characteristics. The integrated circuit is fabricated on a 0.6 µm CMOS process and its supply voltage is 5 V. The integrated circuit includes a filter under test (FUT), a four-phase square wave generator, several analog switches and differential amplifiers to amplify the high-impedance signals of the RCPF. This FUT is a third-order complex RCPF whose passband is 8 − 40 MHz. This paper describes the design of these circuits in detail. This integrated circuit can select two measurement methods by means of external control signals. The first method uses a four-phase square wave. The frequency characteristics are measured by using an on-chip four-phase square wave generator driven by an external clock generator and by a spectrum analyzer tuned to the fundamental frequency. The second method uses an external network analyzer. Furthermore, this integrated circuit is equipped with a calibration circuit to measure the frequency characteristics of the circuitry except FUT by passing through the input / output signals of the FUT. As a result, the frequency characteristics of the FUT itself can be accurately measured. The effectiveness is confirmed through evaluation of the fabricated integrated circuit. © 2025 The Institute of Electrical Engineers of Japan.

关键词： Differential amplifiers

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Mercury Level in Worldwide Poultry Food Products: a Systematic Review

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Biological Trace Element Research 2025年 1-12页

作者： Alves, Ana Clara Nogueira de Almeida Santos, Adriene Núzia dos Santos, Suelen Miranda Carvalho, Junior Ribeiro Rufino, João Paulo Ferreira de Oliveira, Adriano Teixeira Animal Morphophysiology Laboratory Federal Institute of Education Science and Technology of Amazonas (IFAM) AM Manaus 69020-120 Brazil Graduate Program in Animal Science and Fisheries Resources (PPGCARP) Faculty of Agricultural Sciences (FCA) Federal University of Amazonas (UFAM) AM Manaus 69077-000 Brazil Amazonas Scientific Technical Police Department AM Manaus Brazil Institute of Biological Sciences (ICB) Federal University of Amazonas (UFAM) AM Manaus 69077-000 Brazil

Mercury is a metal known for its toxic effects on environmental, animal and human health. The presence of Hg in poultry and its potential impact on food safety still need to be explored, especially considering that poultry is the most consumed source of protein in the global population. This study aimed to systematically review mercury and methylmercury levels in poultry meat and eggs worldwide. The searches were conducted in the Web of science, PubMed, and Scopus databases, resulting in 123 studies, of which only 30 were deemed suitable. Studies were found across sixteen countries: India, Thailand, Malaysia, China, Poland, Egypt, Ghana, Nigeria, Bangladesh, Iran, USA, Italy, Colombia, Romania, Tanzania, Algeria, and Saudi Arabia. Five poultry species were reported, with chicken being the most recorded species in 16 countries. Among biological samples, eggs and liver were the most used for measuring mercury and methylmercury levels. Levels above those permitted by regulatory organizations such as the United States Department of Agriculture (USDA), China's National Health Commission (NHC), and Thailand's Ministry of Public Health — set at 0.05, 0.05, and 0.02 ***⁻¹ respectively — were observed in 12 of the 17 countries, with the highest concentrations detected in chicken eggs from Colombia. Therefore, poultry production is not Hg-free and contamination by this metal must be monitored. © The Author(s), under exclusive licence to Springer science+Business Media, LLC, part of Springer Nature 2025.

关键词： Heavy metals One Health Poultry farm Toxic elements

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Mo-terminated edges in two-dimensional molybdenum disulfide for site-specific hydrolysis and DNA cleavage

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Materials Today 2025年 86卷 162-171页

作者： Wang, Cong Wu, Menghan Li, Muqing Zhao, Yingcan Zhao, Mingchuang Zhang, Yunhao Bai, Yichao Gao, Jianxiang Wang, Xiaoxia Tian, Xilin Zhang, Han Chang, Liang Zou, Xiaolong Liu, Bilu Kang, Feiyu Terrones, Mauricio Lei, Yu Institute of Materials Research Shenzhen Key Laboratory of Advanced Layered Materials for Value-added Applications Guangdong Provincial Key Laboratory of Thermal Management Engineering and Materials & Center of Double Helix Tsinghua Shenzhen International Graduate School Tsinghua University Shenzhen518055 China Institute of Materials Research & Shenzhen Geim Graphene Center Shenzhen Key Laboratory of Advanced Layered Materials for Value-added Applications Tsinghua-Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School Tsinghua University Shenzhen518055 China Environmental Science Program Department of Life Sciences Beijing Normal University-Hong Kong Baptist University United International College Guangdong519087 China Tsinghua Shenzhen International Graduate School Tsinghua University Shenzhen518055 China Department of Physics Department of Chemistry Department of Materials Sciences Center for 2-Dimensional and Layered Materials The Pennsylvania State University University ParkPA16802 United States International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education Institute of Microscale Optoelectronics Shenzhen University Shenzhen518060 China

The hydrolysis of DNA serves as the foundational principle for gene engineering that enable precise gene cleavage at the molecular level. This process typically occurs in biological nucleases, which exhibit nucleobase-selective and catalytic hydrolysis capabilities rarely replicated in abiotic nanomaterials. Here, we demonstrate that molybdenum-terminated (Mo-terminated) edges of molybdenum disulfide (MoS2) possess the unique ability to abstract a proton (H+) from water molecules, thereby facilitating catalytic hydrolysis reactions that cleave the phosphodiester bonds in DNA through the action of hydroxide ions. The enhanced proton absorption at Mo-terminated edges of MoS2 significantly reduces the activation energy required for the DNA hydrolysis reaction. Furthermore, the favorable interaction between the Mo-terminated edges and thymine nucleobases promotes both charge transfer and P-O bond cleavage, enabling targeted DNA hydrolysis at 'TTTTTTT' sequences under dark conditions. This discovery underscores the potential of MoS2 as a stable, efficient nanosystem for precise genetic editing, heralding advanced applications in the field of gene engineering. © 2025 The Author(s)

关键词： Activation energy

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NAD⁺ modulation of intestinal macrophages renders anti-inflammatory functionality and ameliorates gut inflammation

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Biomedicine and Pharmacotherapy 2025年 185卷 117938-117938页

作者： Kim, Young-In Ko, Inseok Yi, Eun-Je Kim, Jusik Hong, Yong Rae Lee, Wheeseong Chang, Sun-Young Laboratory of Microbiology Department of Pharmacy and Research Institute of Pharmaceutical Science and Technology (RIPST) Ajou University Suwon 16499 South Korea Korea Initiative for fostering University of Research and Innovation (KIURI) Program Ajou University School of Medicine Suwon 16499 South Korea Lmito Therapeutics Yongin-si 16827 South Korea Department of Chemistry Education Graduate Department of Chemical Materials Pusan National University Busan South Korea

Macrophages can maintain gut immune homeostasis by driving clearance of infection, but also can prevent chronic inflammation and induce tissue repair. Reduced nicotinamide adenine dinucleotide (NAD⁺) levels in macrophages have been reported to be associated with the onset of severe colitis. Given that dysregulation of gut macrophages plays a significant role in inflammatory bowel disease (IBD), they represent a potential target for novel therapies. Here we show an IBD therapeutic candidate LMT503, a substrate that modulates NADH quinone oxidoreductase (NQO1), which induces anti-inflammatory macrophage polarization by NAD⁺ enhancement. To determine the anti-inflammatory effect of LMT503, a dextran sulfate sodium (DSS)-induced colitis mouse model was used in this study. Treatment of bone marrow-derived macrophages (BMDMs) with LMT503 increased IL-10 and Arg1 levels but decreased levels of TNF-α, iNOS, and IL-6. LMT503 also increased levels of SIRT1, SIRT3, and SIRT6, suggesting that macrophages were driven to an anti-inflammatory character. In a murine DSS-induced colitis model, oral treatment with LMT503 ameliorated colonic inflammation and decreased infiltrating monocytes and neutrophils. Although NAD⁺ enhancement did not alter CX₃CR1^intCD206^- or CX₃CR1^hiCD206⁺ colon macrophage population, it decreased levels of TNF-α and iNOS and increased IL-10 level, with colonic macrophages showing an anti-inflammatory character shift. Depletion of CX₃CR1 expressing gut resident macrophages abrogated the immune regulatory effect of LMT503 in the colon. These data suggest that LMT503 is a therapeutic candidate that can target macrophages to drive polarization with an immunosuppressive character and ameliorate IBD. © 2025

关键词： Colon Gut macrophage Inflammatory bowel disease Macrophage polarization NAD+ modulation

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B(s)→D(s)(*)M decays in the presence of final-state interactions

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Physical Review D 2025年第9期111卷 095020-095020页

作者： Albertus Hariwangsa Panuluh Satoshi Tanaka Hiroyuki Umeeda Department of Physics Education Faculty of Teacher Training and Education Sanata Dharma University Paingan Maguwohardjo Sleman Yogyakarta 55282 Indonesia Physics Program Graduate School of Advanced Science and Engineering Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima 739-8526 Japan Scientific Computational Division Nippon Advanced Information Service (NAIS Co. Inc.) 416 Muramatsu Tokaimura Naka-gun Ibaraki 319-1112 Japan Center for Theoretical Physics and College of Physics Jilin University Changchun 130012 China China Center of Advanced Science and Technology Beijing 100190 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

In light of the recent data for B¯(s)→D(s)(*)P and B¯(s)→D(s)V decays, we perform a model-independent phenomenological analysis in the presence of quasielastic rescattering. With the Wilson coefficients including contributions beyond the standard model, the lifetimes of the B meson and Bd0−B¯d0 mixing are investigated to clarify correlations among the observables. We show that parameter regions for quasielastic rescattering, the size of color-suppressed tree amplitudes, and new physics are constrained due to the lifetime data. As a consequence, it is revealed that this scenario can be tested by the future LHCb measurement of the width difference in Bd0−B¯d0 mixing and semileptonic CP asymmetry.

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Third-order optical properties of Ag nanocubes and Ag@Au hollow nanostructures investigated by femtosecond Z-Scan measurements

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Optik 2025年

作者： Claudevan A. Sousa Antonio F.A.A. Melo Nefe J.B. Silva Tânia Patrícia Silva e Silva Bartolomeu C. Viana Francisco Eroni P. Santos Hans Garcia Department of Physics UFPI - Universidade Federal do Piauí 64049-550 Teresina PI Brazil Materials Engineering Graduate Program Federal Institute of Education Science and Technology of Piauí Central Campus Teresina 64000-040 PI Brazil Interdisciplinary Laboratory for Advanced Materials BioMatLab group Materials Science & Engineering Graduate Program UFPI - Universidade Federal do Piauí 64049-550 Teresina PI Brazil

We present a comprehensive study on the third-order nonlinear optical properties of silver nanocubes (Ag-NCs) and Ag@Au hollow bimetallic nanostructures in aqueous dispersions. The Ag@Au bimetallic nanostructures were synthesized by galvanic replacement of Ag-NCs with gold, generating nanoboxes with surface plasmon resonance (SPR) tunability. Using the femtosecond Z-scan technique (1040 nm, 357 fs) across laser intensities from 99.7 to 279 GW/cm², we identified negative nonlinear refraction in both Ag-NCs and Ag@Au nanoboxes, attributed to hot electron generation. Saturable absorption (SA) was observed only in Ag@Au nanoboxes, distinguishing their potential for nonlinear photonic applications. These findings highlight the impact of morphology and composition on nonlinear refraction and absorption, positioning Ag@Au hollow nanostructures as promising candidates for active media in advanced photonic devices.

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Fostering teachers’ understanding of progression of multiple groups towards the orchestration of conceptual learning

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Unterrichtswissenschaft 2019年第2期47卷 159-176页

作者： Swidan, Osama Prusak, Naomi Livny, Adva Palatnik, Alik Schwarz, Baruch Graduate Program for Science & Technology Education Ben Gurion University of the Negev Be’er Sheva Israel Hebrew University of Jerusalem Jerusalem Israel

Integrating collaborative settings in mathematics classrooms is challenging. The main challenge concerns adaptive guidance—guidance that takes into account the needs of learners. This adaptive guidance depends on the teacher’s understanding of the progression of group work. Understanding this progression when the teacher organizes several groups in a classroom towards conceptual understanding has been impracticable so far. In this paper, we present an environment, the System for Advancing Group Learning in educational Technologies (SAGLET), which is based on the Virtual Math Teams (VMT) environment. This environment allows teachers to observe multiple groups engaging in problem-solving in geometry. SAGLET relies on the theoretical idea of critical moments in group learning, events whose occurrence may enable or impair co-construction of meanings. We conjecture that the teacher’s identification of critical moments may facilitate further guidance towards conceptual learning among students. Machine learning techniques provide online alerts about critical moments. We checked whether 11 teachers looking at multiple groups working in parallel better understand the progression of group work, upon being informed about critical moments. The results indicate that teachers use alerts about critical moments to understand better the progression of parallel groups but that informing them about critical moments sometimes impairs their observations. © 2019, Die Herausgeber und Springer Fachmedien Wiesbaden GmbH, ein Teil von Springer Nature.

关键词： Adaptive guidance Conceptual learning Geometry Orchestration Small groups Technological tools

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Theories for, in, and of Mathematics education

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Interchange 2011年第1期42卷 81-95页

作者： Fried, Michael N. Graduate Program for Science and Technology Education Ben Gurion University of the Negev Beer Sheva P.O. Box 653 Israel

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