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Effects of Mechanical Properties of Elastomeric Electrolytes for Stable Operation of Lithium Metal Batteries
No full textThe mechanical properties of polymer electrolytes are critical for the stable operation of lithium metal batteries (LMBs), as they accommodate volume changes of the lithium (Li) metal anode, suppress dendrite formation, and maintain interfacial stability. Here, we present a systematic investigation into the role of the mechanical characteristics of fluorinated elastomeric electrolytes (FEEs) in enabling stable cycling of LMBs at ambient and low temperatures. The FEEs consist of bicontinuous elastomer and plastic crystal phases, allowing independent control of mechanical properties by adjusting the crosslinking density of the elastomer phase. Concurrently, FEEs retain the fast ion transport properties of the plastic crystal phase, exhibiting high ionic conductivity of approximate to 1.1 and approximate to 0.24 mS cm-1 at 25 and -10 degrees C, respectively. The optimized FEE demonstrates balanced toughness (140.6 kJ m-3) and adhesion energy (31.4 J m-2), along with elastic recovery characteristic, enabling a Li|| LiNi0.8Co0.1Mn0.1O2 full cell to deliver a high initial discharge capacity (153 mAh g-1) with 76% capacity retention after 150 cycles at -10 degrees C. In contrast, lightly crosslinked FEEs undergo irreversible plastic deformation and loss of interfacial contact, while excessively crosslinked systems suffer from low toughness and are prone to fracture, both resulting in poor cycling performance.TRUEsciescopu
Advances in biomaterial-based composite spheroid for articular cartilage regeneration
No full textArticular cartilage plays a crucial role in reducing friction between bones and enabling movements; however, it is frequently degraded due to persistent joint stress, aging, and osteoarthritis. As its self-repair ability is limited, various cell-based therapeutic strategies have been developed for cartilage regeneration. Conventional two-dimensional (2D) cell cultures inadequately replicate the complex intercellular interactions of native cartilage. In contrast, three-dimensional (3D) cell spheroid cultures can more accurately mimic in vivo cellular physiology, offering superior regenerative potential via improved cell-cell and cell-matrix interactions. These interactions can be enhanced with biomaterials to form composite spheroids, which exhibit substantial potential for improving cartilage regeneration and attenuating osteoarthritis progression in vivo by promoting cell survival and tissue integration. This review highlights current strategies for developing biomimetic composite spheroid systems, including spheroid encapsulation, scaffold incorporation, and 3D bioprinting. Furthermore, we discuss their advantages, translational potential for in vivo cartilage repair, and the challenges and future directions in cartilage tissue engineering.TRUEsciescopu
Bio-Inspired Strategy for Radiation-Based Thermal Management and Utilization
No full textIn nature, biological species have evolved unique mechanisms and sophisticated structures for intelligent radiation-based thermal management and utilization over billions of years through natural selection. These adaptive strategies in biological species serve as a significant source of inspiration for the development of advanced thermal engineering materials and systems in modern society, driving innovation in applications such as building heating and cooling, personal thermal management, water acquisition, and next-generation infrared (IR) sensing systems. In this review, advancements in biological and bio-inspired thermal management strategies, including radiative cooling, thermal regulation, and thermal insulation, are comprehensively summarized. Additionally, recent advancements in radiation-based biological and bio-inspired thermal utilization are discussed, focusing on applications such as water harvesting, IR camouflage, and IR detection. Next, various examples of the integration of IR management strategies with electronic and energy systems are introduced, highlighting their potential to enhance efficiency and functionality in thermal management, energy efficiency, and advanced sensing applications. By leveraging these bio-inspired systems, innovative strategies have emerged, encompassing both thermal management and utilization, and enabling efficient heat regulation and energy harvesting across a wide range of technological applications. Finally, a future perspective on the development of radiation-based bio-inspired thermal management and utilization technologies is provided.FALSEsciescopu
Design, Synthesis, and Biological evaluation of Pyridine-based derivatives to enhance motile cilia
No full textMotile cilia are crucial for maintaining healthy bodily functions by facilitating fluid transport and removing foreign substances or debris from the body. The dysfunction of motile cilia leads to ciliopathy. In particular, damage to the motile cilia of the airways can cause or worsen respiratory disease, making it an attractive target for therapeutic interventions. However, there are no treatments to induce motile ciliogenesis. Forkhead box transcription factor J1 (FOXJ1), the master regulator, has been implicated in motile cilia formation. Mice lacking the Foxj1 gene show loss of axoneme, a key component of cilia, that further highlights the importance of FOXJ1 in motile cilia formation. This prompted us to identify new small molecules that could induce motile ciliogenesis. A phenotype-based high-throughput screening (HTS) in a Tg(foxj1a:eGFP) zebrafish model was performed and a novel hit compound was identified. Among the synthesized compounds, compound 16c effectively enhanced motile ciliogenesis in a transgenic zebrafish model. To further test the efficacy of compound 16c on a mammalian airway system consisting of multiciliated cells (MCCs), ex vivo mice tracheal epithelial cell culture was adopted under an air-liquid interface system (ALI). Compound 16c significantly increased the number of MCCs by enhancing motile ciliogenesis. In addition, compound 16c exhibited good liver microsomal stability, in vivo PK profiles with AUC, and oral bioavailability. There was no significant inhibition of CYP and hERG, and no cell cytotoxicity was shown. In an elastase-induced COPD (chronic obstructive pulmonary disease) mouse model, compound 16c effectively prevented the development and onset of COPD. Taken together, compound 16c has great promise as a therapeutic agent for treating and alleviating motile ciliopathies.DoctorAbstract i
List of Schemes iv
List of Tables v
List of Figures vi
Part 1 1
I. Introduction 2
1.1. Motile ciliopathies 2
1.2. Motile cilia 3
1.3. FOXJ1 plays a key regulatory role in motile polyciliogenesis 4
1.4. Zebrafish as an animal model for high-throughput screening 6
II. Results and Discussion 7
III. Conclusion 22
IV. Experimental procedures 23
4.1. Materials 23
V. References 40
Part 2. 43
I. Introduction 44
II. Results and Discussion 46
III. Conclusion 59
IV. Experimental procedures 60
4.1. Materials 60
V. References 69
Supporting Information 7
Automated Sound-Visualized Caption System to Enhance Accessibility for Deaf and Hard-of-Hearing Users: Focus on Speech and Non-Speech Sound Nuances
No full textThe sounds around us create rich information—such as intent, emotion, and atmosphere—through both linguistic and paralinguistic cues. For individuals who are deaf or hard-of-hearing, these layers of auditory information are often inaccessible, highlighting the need to translate sound into visual formats. Captions have been a powerful tool in this endeavor, providing a visual means to interpret sounds and enabling users to interact with sound visually. However, conventional caption systems mainly focus on spoken words or basic sound categories, limiting their ability to convey sound nuances. This limitation restricts the depth of experience for users who rely on captions to fully engage with audio-rich content. Recent advances in artificial intelligence (AI)-based sound recognition technologies have improved caption quality by accurately identifying speech and sound classes. Still, there has been limited research on recognizing and visualizing paralinguistic expressions. Due to the scarcity of datasets and studies related to sound nuances, research on sound-visualized captions remains challenging. To address this gap, this thesis proposes sound-visualized caption systems that automatically visualize nuanced information into captions. These systems include both speech and non-speech visualizations, using ty- pographic design and punctuation to express speech nuances, and onomatopoeic descriptions to represent non- speech sound nuances. Specifically, this work explores methodologies for mapping caption design elements to effectively convey sound nuances, techniques for recognizing these nuances, and a system architecture that generates sound-visualized captions from auditory input. This thesis not only presents a novel framework for implementing sound-visualized captions but also offers an empirical understanding of how these captions can enhance sound accessibility and viewing experiences for deaf and hard-of-hearing users. In addition, it discusses the potential benefits and challenges of sound- visualized captions, design implications for improving the proposed systems, and future research opportunities to connect with other studies on sound accessibility and bidirectional sound-text conversion.DoctorAbstract i
List of Contents ii
List of Tables vii
List of Figures viii
1 Introduction 1
1.1 Background and Motivation 1
1.2 Thesis Overview 3
1.3 Contributions 4
2 Related Work 5
2.1 Sound content in Current Captioning 5
2.2 Information Visualization through Text 7
2.3 Sound Visualization in Caption Design 8
2.4 Sound Recognition Technology 9
2.5 Summary of Related Work 11
I Making Speech Sound Accessible 13
3 Visualizing Speech Nuances in Captions 14
3.1 Background and Research Questions 14
3.2 Design Study 15
3.2.1 Survey 15
3.2.2 Design Workshop 16
3.3 System Design 18
3.3.1 Tone 19
3.3.2 Volume and Pitch 20
3.3.3 Implementation Details 23
3.4 User Study 23
3.4.1 Participants 24
3.4.2 Study Procedure 24
– ii –
3.4.3 Materials 26
3.4.4 Measurement 26
3.5 Results 27
3.5.1 Objective Task Performance in Speech Accessibility 27
3.5.2 Subjective Evaluation on the Accessibility of Paralinguistic Cues . 29
3.5.3 Legibility and Cognitive Load 32
3.5.4 Satisfaction 34
3.5.5 Preferences 34
3.5.6 Analysis of the Effectiveness of Sound-Visualized Captions 36
3.6 Discussion 38
3.7 Conclusion 40
4 Visualizing Speech Style in Captions 41
4.1 Introduction 41
4.2 System Design 43
4.2.1 Fundamental Audio Feature Extraction 44
4.2.2 Speech Style Detection Algorithm 45
4.3 User Study 48
4.3.1 Participants 49
4.3.2 Study Procedure 49
4.3.3 Materials 50
4.3.4 Measurement 51
4.4 Results 51
4.4.1 Enhanced Accessibility to Speech Styles with Visual Cues 51
4.4.2 Legibility Competitive with Common Captions 55
4.4.3 Satisfaction and Preferences 57
4.4.4 Acclimation to the Proposed Caption System 58
4.5 Discussion 60
4.6 Conclusion 62
– iii –
II Making Non-speech Sound Accessible 63
5 Transcribing Non-speech Sounds to Onomatopoeic Descriptions 64
5.1 Introduction 64
5.2 Sound-to-Onomatopoeia Dataset 65
5.2.1 Audio Data 66
5.2.2 Annotation Procedure 66
5.2.3 Data Pre-processing 67
5.3 Sound-to-Onomatopoeia Transcription Model 68
5.3.1 Model Architecture 68
5.3.2 Model Details 69
5.4 Model Evaluation 70
5.4.1 Experimental Setup 70
5.4.2 Objective Evaluation 71
5.4.3 Subjective Evaluation 73
5.5 Conclusion 75
6 Enriching Non-speech Sound Captions with Onomatopoeic Descriptions 77
6.1 Introduction 77
6.2 Preliminary Study 79
6.2.1 Participants 79
6.2.2 Methods 80
6.2.3 Pre-survey Results 81
6.3 System Design 83
6.4 User Study 84
6.4.1 Participants 84
6.4.2 Study Setup 85
6.4.3 Materials 85
6.4.4 Measurements 88
6.5 Results 89
6.5.1 Perceived Sound Accessibility 89
6.5.2 Perceived Experience of Non-speech Sound Captions 90
6.5.3 Benefits of Onomatopoeic Expressions in Non-speech Sound Captions 92
– iv –
6.5.4 Challenges of Onomatopoeic Expressions in Non-speech Sound Cap-
tions 95
6.5.5 Genre Suitability 97
6.5.6 Perceived of AI-generated Onomatopoeic Captions 98
6.5.7 Preferences 99
6.6 Discussion 99
6.7 Conclusion 101
III Concluding Remarks 102
7 Conclusion 103
7.1 Summary of Findings 103
7.2 Design Implications 106
7.2.1 Balance Legibility with Expressiveness 106
7.2.2 Provide Time to Acclimate to the Visualization 106
7.2.3 Focus on Metaphorical Meaning 107
7.2.4 Adjust Setting based on Video Genres 107
7.2.5 Minimize Mismatches between Video Content and Sound-Visualized
Captions 108
7.2.6 Provide Customizable Interface 108
7.3 Future Opportunities for Improvements 109
7.4 Expanding Audience of This Thesis 111
7.5 Future Directions 112
Summary 113
References 114
A Metadata for Displaying Sound-Visualized Captions 135
B Speech Style Detection for Streaming 136
C Supplementary Material for ONOMACAP Study 139
C.1 Category Information for Sound-to-Onomatopoeia Data Collection 139
– v –
C.2 Video Information 139
Acknowledgements 143
– vi
Optimizing Crosslinking Density and Electrical Conductivity for the Potential Application of Multifunctional Electrically Conductive Nerve Guidance Conduits with Immune Compatibility and Nerve Regeneration Capabilities
No full textPeripheral nerve injury (PNI) remains a significant clinical challenge due to its complex repair mechanisms and limited regenerative capacity. To address this issue, nerve guidance conduits (NGCs) have been developed as a promising strategy for structural and functional nerve regeneration. In this study, I prepared various conductive hydrogels using gelatin methacryloyl (GelMA) and reduced graphene oxide (rGO) for potential NGC applications with high nerve regeneration efficacy. Specifically, by varying the reduction time of rGO and gelation time of the GelMA hydrogel, I synthesized four types of hydrogels with different conductivity and crosslinking density: 1) low crosslinking density and low conductivity, 2) low crosslinking density and high conductivity, 3) high crosslinking density and low conductivity, and 4) high crosslinking density and high conductivity. These hydrogels were characterized for their physicochemical, mechanical, and electrical properties to evaluate their potential as artificial NGCs. In vitro studies revealed that hydrogels with high crosslinking density and high conductivity showed superior performance for nerve regeneration, as evidenced by significantly enhanced neural outgrowth in dorsal root ganglion (DRG) neurons and anti-inflammatory character by inducing M2 phenotype in bone marrow- derived macrophages (BMDMs). Moreover, the application of electrical stimulation (ES) further augmented these effects. The findings highlight the critical roles of electrical conductivity and crosslinking density in designing effective NGCs and offer new insights into optimizing NGC properties for peripheral nerve repair.MasterAbstract ii
Contents iii
List of Figures v
Chapter 1. Introduction 1
1.1. Overview of peripheral nerve injury and therapeutic treatment 1
1.2. Various characteristics for effective nerve guidance conduit 2
1.3. Electrical stimulation for regeneration of peripheral nerve 3
1.4. Experimental overview 4
Chapter 2. Materials and Methods 6
2.1. Materials 6
2.2. Methods 6
2.2.1. Synthesis of GelMA 6
2.2.2. Preparation of MMT 6
2.2.3. Fabrication of conductive hydrogels 7
2.2.4. Scanning electron microscopy (SEM) 7
2.2.5. Raman spectroscopic anlysis. 7
2.2.6. Mechanical property of conductive hydrogels 7
2.2.7. EIS and electrical conductivity of conductive hydrogels 8
2.2.8. In vitro PC12 cell studies 8
2.2.9. In vitro primary Bone marrow-derived macrophage (BMDM) cultures 9
2.2.10. Enzyme-linked immunosorbent assay (ELISA). 10
2.2.11. Immunofluorescence staining 10
2.2.12. RT-PCR 10
2.2.13. In vitro primary dorsal root ganglion(DRG) studies 10
Chapter 3. Results and Discussion 13
3.1. Fabrication of Conductive Hydrogels 13
3.2. Materials characterization of the composite hydrogels 16
3.2.1. Raman spectroscopy of the composite hydrogels 16
3.2.2. Mechanical and electrical properties of the composite hydrogels 17
3.3. In Vitro test of the Composite Hydrogels. 19
3.3.1. In Vitro PC12 Cell culture 19
3.3.2. In Vitro primary BMDMs Cell culture 21
3.3.3. In Vitro DRG Cell culture 24
Chapter 4. Conclusion 26
Reference 27
Acknowledgments 3
The relationship between aging and inhibition ability:Evidence from a web-based Number Stroop task
No full text본 연구의 목적은 방해 자극에 대한 억제 능력을 측정하는 숫자 스트룹(Number Stroop) 과제를 사용하여 연령에 따른 억제 능력의 차이를 알아보는 것이다. 참가자들은 20세부터 69세까지의 성인들로, 이 과제의 자극으로는 1에서 4까지의 숫자들이 1개에서 4개 사이로 구성된 숫자열이 제시되었다. 제시되는 숫자열은 일치 조건과 불일치 조건으로 구분되는데, 일치 조건(예: 333)은 숫자열을 구성하고 있는 숫자와 자극의 개수가 같은 자극으로 두 개의 정보가 같으므로 간섭이 최소화된다. 이에 반해 자극의 숫자와 개수가 다른 불일치 조건(예: 33)은 의식적으로 방해 자극의 영향을 억제하면서 목표 정보에 주의를 두어야 하므로 일치 조건에 비해 의식적인 억제 정보처리가 요구된다. 이 실험에서 참가자들은 제시되는 숫자열(예: 33)을 보고 자극의 속성(예: 3)이 아니라 자극의 개수(예: 두 개)를 최대한 빠르고 정확하게 보고하는 과제를 수행했다. 연구 결과, 연령이 증가할수록 과제 수행 시간은 늘어났고, 일치 조건에 비해 불일치 조건의 수행 시간이 느려졌다. 참가자의 나이와 스트룹 효과의 크기 간의 상호작용 효과는 40대와 50대 사이에서만 유의미했다. 보다 구체적으로 불일치 조건에서는 두 연령 집단의 반응시간 차이가 없었던데 반해, 일치 조건에서는 50대가 40대에 비해 느리게 반응하는 특성이 관찰되었다. 이는 50대 성인들이 노화로 인해 인지 능력이 저하됨에 따라 상대적으로 쉬운 일치 조건에서도 더 신중하게 판단하고 있음을 시사한다. 또한 갈등 과제를 위한 확산 모형(DMC)을 이용한 분석결과에서도 나이가 들수록 과제 수행 상황에서 더욱 신중한 전략을 취하는 경향이 나타났다. 본 연구는 노화에 따른 억제 능력의 감소가 50대부터 두드러지며, 이러한 인지 변화가 과제 수행 시 신중한 전략을 사용하도록 하는데, 이는 일치 조건과 같이 더 쉬운 과제 상황에서 뚜렷이 나타날 수 있음을 보여주었다. 나아가, 다양한 연령대의 참가자가 참여한 실험 데이터를 바탕으로 한 모델링 분석을 통해 연령 집단별 과제 수행 전략의 변화를 확인함으로써, 노화에 따른 억제 과제 수행 방식의 변화를 종합적으로 이해할 수 있었다.FALSEkc
Merging rules for strong structural controllability and minimum input problem in undirected networks
No full textThis paper explores the conditions for strong structural controllability in structured networks determined by the zero/non-zero patterns of edges. For undirected networks, starting with the fundamental unit for controllability, the path graph, we investigate the strong structural controllability of larger components such as cycles, trees, and ultimately, a pactus (a generalization of the well-known cactus graph) through the merging rules. In this process, we introduce the notion of a component input node, which functions identically to an external input node, providing a new perspective on how internal nodes can facilitate controllability. Furthermore, we offer an intuitive interpretation by decomposing complex graph structures into simpler path graphs and applying merging rules to understand how disjoint controllable components can merge to maintain overall controllability. Finally, we present an algorithm to solve the minimum input problem in a pactus, which leverages the concept of component input nodes to optimize the number of external inputs for strong structural controllability. © 2025 The Franklin InstituteFALSEsciescopu
Investigation of pH swing carbon mineralization for valuable element recovery and CO2 sequestration using steelmaking slag
No full textCarbon capture, utilization, and storage (CCUS) technology is a key approach to mitigate climate change and achieve net-zero emissions. Among CCUS technologies, ex-situ carbon mineralization via pH swing processes using steelmaking slag presents dual benefits: resource recovery and CO2 reduction through CaCO3 production. However, challenges like co-precipitation and solubility issues require further investigation. Here, we explore the in-depth elemental precipitation behavior using basic oxygen furnace (BOF) and kanbara reactor (KR) slags. Elements were extracted using 2 M HCl solution and sequentially precipitated by adjusting the pH from 5 to 10 with 2 M NaOH solution. CO2 gas was then bubbled to generate CaCO3. Major elements (Ca, Mg, Fe, Mn, Si, Al) and minor elements (Ti, Cr, Cu) were identified. Al, Si, Ti, and Cr precipitated at pH 3.5–5, Fe and Cu at pH 7–8, Mn at pH 8–9, Mg at pH 10, while Ca remained in solution for carbonation at pH 10. The precipitation behavior was dependent on the solubility of each element (Ksp) and affinity for hydroxide ions (OH−). The purities of CaCO3 from BOF and KR slags were 98.4 % and 97.4 %, with CO2 storage capacities of 93 kg/t slag and 131 kg/t slag, respectively.FALSEsciescopuskc