Biomimetics最新文献_第5页

Biomimetic Design and Assessment via Microenvironmental Testing: From Food Packaging Biomaterials to Implantable Medical Devices. 基于微环境测试的仿生设计与评估：从食品包装生物材料到植入式医疗器械。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-05 DOI: 10.3390/biomimetics10060370

Diana V Portan, Athanasia Koliadima, John Kapolos, Leonard Azamfirei

{"title":"Biomimetic Design and Assessment via Microenvironmental Testing: From Food Packaging Biomaterials to Implantable Medical Devices.","authors":"Diana V Portan, Athanasia Koliadima, John Kapolos, Leonard Azamfirei","doi":"10.3390/biomimetics10060370","DOIUrl":"10.3390/biomimetics10060370","url":null,"abstract":"Biomaterials and biomedical devices interact with the human body at different levels. At one end of the spectrum, medical devices in contact with tissue pose risks depending on whether they are deployed on the skin or implanted. On the other hand, food packaging and associated material technologies must also be biocompatible to prevent the transfer of harmful molecules and contamination of food, which could impact human health. These seemingly unlinked domains converge into a shared need for the elaboration of new laboratory evaluation protocols that consider recent advances in biomaterials and biodevices, coupled with increasing legal restrictions on the use of animal models. Here, we aim to select and prescribe physiologically relevant microenvironment conditions for biocompatibility testing of novel biomaterials and biodevices. Our discussion spans (1) the development of testing protocols according to material classes, (2) current legislation and standards, and (3) the preparation of biomimetic setups that replicate the microenvironment, with a focus on the multidisciplinary dimension of such studies. Testing spans several characterization domains, beginning with chemical properties, followed by mechanical integrity and, finally, biological response. Biomimetic testing conditions typically include temperature fluctuations, humidity, mechanical stress and loading, exposure to body fluids, and interaction with multifaceted biological systems.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12190333/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Effects of the Substrate Length and Cultivation Time on the Physical and Mechanical Properties of Mycelium-Based Cushioning Materials from Salix psammophila and Peanut Straw. 基质长度和培养时间对沙柳和花生秸秆菌丝体基缓冲材料物理力学性能的影响

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-05 DOI: 10.3390/biomimetics10060371

Xiaowen Song, Shuoye Chen, Jianxin Wu, Ziyi Cai, Yanfeng Zhang, Risu Na, He Lv, Cong He, Tingting Wu, Xiulun Wang

{"title":"The Effects of the Substrate Length and Cultivation Time on the Physical and Mechanical Properties of Mycelium-Based Cushioning Materials from Salix psammophila and Peanut Straw.","authors":"Xiaowen Song, Shuoye Chen, Jianxin Wu, Ziyi Cai, Yanfeng Zhang, Risu Na, He Lv, Cong He, Tingting Wu, Xiulun Wang","doi":"10.3390/biomimetics10060371","DOIUrl":"10.3390/biomimetics10060371","url":null,"abstract":"Mycelium-based biocomposites represent a novel class of environmentally friendly materials. This study investigated the potential of using Salix psammophila and peanut straw as substrates for cultivating Pleurotus ostreatus and Ganoderma lucidum, respectively, to fabricate mycelium-based cushioning materials. The results demonstrated that the Pleurotus ostreatus-based cushion material using Salix psammophila (POSM) outperformed the Ganoderma lucidum-based cushion material using peanut straw (GLPM) in terms of overall performance. Both materials presented optimal comprehensive properties when the cultivation period reached 30 days. Increasing the substrate length enhanced most of the material properties. The resulting density ranged from 0.13 to 0.16 g/cm3, which was higher than that of polystyrene foam. The contact angles of both materials exceeded 120°, whereas their elastic springback rates reached 50.2% and 43.2%, and their thermal conductivities were 0.049 W/m·K and 0.051 W/m·K, respectively. Additionally, thermogravimetric analysis revealed that both materials exhibited similar thermal degradation behavior and relatively high thermal stability. These findings align with those of previous studies on mycelium composites and indicate that the physical and mechanical properties of the materials are largely comparable to those of expanded polystyrene (EPS). In conclusion, the developed mycelium-based cushioning materials promote the efficient utilization of agricultural residues and hold promise as a sustainable alternative to EPS, offering broad application prospects in the transportation and packaging sectors.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12191277/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Holistic Education for a Resilient Future: An Integrated Biomimetic Approach for Architectural Pedagogy. 面向弹性未来的全人教育：建筑教育学的综合仿生方法。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-05 DOI: 10.3390/biomimetics10060369

Lidia Badarnah

{"title":"Holistic Education for a Resilient Future: An Integrated Biomimetic Approach for Architectural Pedagogy.","authors":"Lidia Badarnah","doi":"10.3390/biomimetics10060369","DOIUrl":"10.3390/biomimetics10060369","url":null,"abstract":"The pressing need to address climate change and environmentally related challenges highlights the importance of reimagining educational approaches to equip students with the skills required for innovation and sustainability. This study proposes a novel holistic pedagogic framework for architectural education that integrates biomimicry, systems thinking, and Bloom's Revised Taxonomy to advance innovation, sustainability, and transformative learning. Developed through a triangulated methodological approach-combining reflective practitioner inquiry, design-based research, and conceptual model development-the framework draws from multiple theoretical perspectives to create a cognitively structured, interdisciplinary, and ecologically grounded educational model. Bloom's Taxonomy provides a scaffold for learning progression, while the Function-Structure-Behavior (FSB) schema enhances the establishment of cross-disciplinary bridges to enable students to address complex design challenges. The framework is informed by insights from the literature and patterns observed in bio-inspired studios, student projects, and interdisciplinary workshops. These examples highlight how the approach supports systems thinking, ecological literacy, and ethical decision-making through iterative, experiential, and metacognitive learning. Rather than offering a fixed intervention, the framework is presented as a flexible, adaptable model that aligns learning outcomes with real-world complexity. It enables learners to navigate interdisciplinary knowledge, reflect critically on design processes and co-create regenerative solutions. By positioning nature as mentor, model, and measure, this pedagogic framework reimagines architectural education as a catalyst for sustainability and systemic change in the built environment.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12190790/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Decentralized Multi-Robot Navigation Based on Deep Reinforcement Learning and Trajectory Optimization. 基于深度强化学习和轨迹优化的分散多机器人导航。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-04 DOI: 10.3390/biomimetics10060366

Yifei Bi, Jianing Luo, Jiwei Zhu, Junxiu Liu, Wei Li

{"title":"Decentralized Multi-Robot Navigation Based on Deep Reinforcement Learning and Trajectory Optimization.","authors":"Yifei Bi, Jianing Luo, Jiwei Zhu, Junxiu Liu, Wei Li","doi":"10.3390/biomimetics10060366","DOIUrl":"10.3390/biomimetics10060366","url":null,"abstract":"Multi-robot systems are significant in decision-making capabilities and applications, but avoiding collisions during movement remains a critical challenge. Existing decentralized obstacle avoidance strategies, while low in computational cost, often fail to ensure safety effectively. To address this issue, this paper leverages graph neural networks (GNNs) and deep reinforcement learning (DRL) to aggregate high-dimensional features as inputs for reinforcement learning (RL) to generate paths. Additionally, it introduces safety constraints through an artificial potential field (APF) to optimize these trajectories. Additionally, a constrained nonlinear optimization method further refines the APF-adjusted paths, resulting in the development of the GNN-RL-APF-Lagrangian algorithm. By combining APF and nonlinear optimization techniques, experimental results demonstrate that this method significantly enhances the safety and obstacle avoidance capabilities of multi-robot systems in complex environments. The proposed GNN-RL-APF-Lagrangian algorithm achieves a 96.43% success rate in sparse obstacle environments and 89.77% in dense obstacle scenarios, representing improvements of 59% and 60%, respectively, over baseline GNN-RL approaches. The method maintains scalability up to 30 robots while preserving distributed execution properties.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12190238/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of an Oblique Cone Dielectric Elastomer Actuator Module-Connected Vertebrate Fish Robot. 斜锥介质弹性体致动器模块连接脊椎动物鱼机器人的研制。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-04 DOI: 10.3390/biomimetics10060365

Taro Hitomi, Ryuki Sato, Aiguo Ming

{"title":"Development of an Oblique Cone Dielectric Elastomer Actuator Module-Connected Vertebrate Fish Robot.","authors":"Taro Hitomi, Ryuki Sato, Aiguo Ming","doi":"10.3390/biomimetics10060365","DOIUrl":"10.3390/biomimetics10060365","url":null,"abstract":"As a soft actuator for fish robots, an oblique cone dielectric elastomer actuator (DEA) module inspired by the structure of white muscles in fish was proposed in the authors' previous study. However, a mathematical model of an oblique cone DEA was not established, and designing a drive module that took into account its driving characteristics and passivity for integration into a fish robot remained a challenge. The purpose of this paper is to develop a vertebrate fish robot using multiple oblique cone DEA modules to achieve fish-like bending capability. First, an oblique cone DEA module was modeled for the design of a fish robot. The relationships among bending angle, blocking torque, driving voltage, and design parameters were established and confirmed by comparing the calculated and experimental results. Based on the modeling results, we designed an oblique cone DEA module-connected vertebrate fish robot. Finally, the experimental results of the fabricated fish robot demonstrated that the model-based design enabled flexible body swinging and swimming through a multiple-module-connected vertebrate structure.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12191322/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Lightweight Bioinspired SMA-Based Grasping Mechanism for Flapping Wing MAVs. 扑翼飞行器轻量化仿生sma抓握机构研究。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-04 DOI: 10.3390/biomimetics10060364

Ahmad Hammad, Mehmet Süer, Sophie F Armanini

{"title":"A Lightweight Bioinspired SMA-Based Grasping Mechanism for Flapping Wing MAVs.","authors":"Ahmad Hammad, Mehmet Süer, Sophie F Armanini","doi":"10.3390/biomimetics10060364","DOIUrl":"10.3390/biomimetics10060364","url":null,"abstract":"This study presents a novel, bioinspired perching mechanism designed to enhance the landing and takeoff capabilities of flapping wing micro aerial vehicles (FWMAVs). Drawing inspiration from the human hand, the lightweight gripper integrates a compliant claw structure actuated by shape memory alloys (SMAs) that mimic muscle movement. These SMA springs act as compact, lightweight substitutes for traditional actuators like motors or solenoids. The mechanism operates via short electrical impulses that trigger both opening and closing motions. A detailed design process was undertaken to optimize phalange lengths for cylindrical grasping and to select appropriate SMAs for reliable performance. Weighing only 50 g, the gripper leverages the high power-to-weight ratio and flexibility of SMAs, with the springs directly embedded within the phalanges to reduce size and mass while preserving high-force output. Experimental results demonstrate fast actuation and a grasping force of approximately 16 N, enabling the gripper to hold objects of varying shapes and sizes and perform perching, grasping, and carrying tasks. Compared to existing solutions, this mechanism offers a simpler, highly integrated structure with enhanced miniaturization and adaptability, making it especially suitable for low-payload MAV platforms like FWMAVs.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12191329/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Topology-Dependent Antifreeze Properties of Biomimetic Linear and Star-Shaped Peptoids. 仿生线性和星形肽体拓扑相关的防冻性能。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-04 DOI: 10.3390/biomimetics10060368

Lei Feng, Liugen Xu, Junhao Wen, Minghai Zhao, Amjad Ali, Naushad Ahmad, Jianwei Lu, Li Guo

引用次数: 0

UWB Indoor Localization Based on Artificial Rabbit Optimization Algorithm and BP Neural Network. 基于人工兔子优化算法和BP神经网络的超宽带室内定位。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-04 DOI: 10.3390/biomimetics10060367

Chaochuan Jia, Can Tao, Ting Yang, Maosheng Fu, Xiancun Zhou, Zhendong Huang

{"title":"UWB Indoor Localization Based on Artificial Rabbit Optimization Algorithm and BP Neural Network.","authors":"Chaochuan Jia, Can Tao, Ting Yang, Maosheng Fu, Xiancun Zhou, Zhendong Huang","doi":"10.3390/biomimetics10060367","DOIUrl":"10.3390/biomimetics10060367","url":null,"abstract":"In the field of ultra-wideband (UWB) indoor localization, traditional backpropagation neural networks (BPNNs) are limited by their susceptibility to local minima, which restricts their ability to achieve global optimization. To overcome this challenge, this paper proposes a novel hybrid algorithm, termed ARO-BP, which integrates the Artificial Rabbit Optimization (ARO) algorithm with a BPNN. The ARO algorithm optimizes the initial weights and thresholds of the BPNN, enabling the model to escape local optima and converge to a global solution. Experiments were conducted in both line-of-sight (LOS) and non-line-of-sight (NLOS) environments using a four-base-station configuration. The results demonstrate that the ARO-BP algorithm significantly outperforms traditional BPNNs. In LOS conditions, the ARO-BP model achieves a localization error of 6.29 cm, representing a 49.48% reduction compared to the 12.45 cm error of the standard BPNN. In NLOS scenarios, the error is further reduced to 9.86 cm (a 46.96% improvement over the 18.59 cm error of the baseline model). Additionally, in dynamic motion scenarios, the trajectory predicted by ARO-BP closely aligns with the ground truth, demonstrating superior stability. These findings validate the robustness and precision of the proposed algorithm, highlighting its potential for real-world applications in complex indoor environments.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12191330/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Biomimetic Visual Information Spatiotemporal Encoding Method for In Vitro Biological Neural Networks. 体外生物神经网络仿生视觉信息时空编码方法。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-03 DOI: 10.3390/biomimetics10060359

Xingchen Wang, Bo Lv, Fengzhen Tang, Yukai Wang, Bin Liu, Lianqing Liu

{"title":"Biomimetic Visual Information Spatiotemporal Encoding Method for In Vitro Biological Neural Networks.","authors":"Xingchen Wang, Bo Lv, Fengzhen Tang, Yukai Wang, Bin Liu, Lianqing Liu","doi":"10.3390/biomimetics10060359","DOIUrl":"10.3390/biomimetics10060359","url":null,"abstract":"The integration of in vitro biological neural networks (BNNs) with robotic systems to explore their information processing and adaptive learning in practical tasks has gained significant attention in the fields of neuroscience and robotics. However, existing BNN-based robotic systems cannot perceive the visual environment due to the inefficiency of sensory information encoding methods. In this study, we propose a biomimetic visual information spatiotemporal encoding method based on improved delayed phase encoding. This method transforms high-dimensional images into a series of pulse sequences through convolution, temporal delay, alignment, and compression for BNN stimuli. We conduct three stages of unsupervised training on in vitro BNNs using high-density microelectrode arrays (HD-MEAs) to validate the potential of the proposed encoding method for image recognition tasks. The neural activity is decoded via a logistic regression model. The experimental results show that the firing patterns of BNNs with different spatiotemporal stimuli are highly separable in the feature space. After the third training stage, the image recognition accuracy reaches 80.33% ± 7.94%, which is 13.64% higher than that of the first training stage. Meanwhile, the BNNs exhibit significant increases in the connection number, connection strength, and inter-module participation coefficient after unsupervised training. These results demonstrate that the proposed method significantly enhances the functional connectivity and cross-module information exchange in BNNs.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12190828/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Inversion of Biological Strategies in Engineering Technology: A Case Study of the Underwater Soft Robot. 工程技术中的生物策略反转：以水下软机器人为例。

IF 3.4 3区医学

Biomimetics Pub Date : 2025-06-03 DOI: 10.3390/biomimetics10060362

Siqing Chen, He Xu, Xueyu Zhang, Tian Jiang, Zhen Ma

{"title":"Inversion of Biological Strategies in Engineering Technology: A Case Study of the Underwater Soft Robot.","authors":"Siqing Chen, He Xu, Xueyu Zhang, Tian Jiang, Zhen Ma","doi":"10.3390/biomimetics10060362","DOIUrl":"10.3390/biomimetics10060362","url":null,"abstract":"Bio-inspired design, a paradigm-shifting methodology that translates evolutionary mechanisms into engineering solutions, has established itself as a cornerstone for pioneering innovation in multifaceted technological systems. Despite its promise, the inherent complexity of biological systems and interdisciplinary knowledge gaps hinder the effective translation of biological principles into practical engineering solutions. This study introduces a structured framework integrating large language models (LLMs) with a function-behavior-characteristic-environment (F-B-C-E) paradigm to systematize biomimetic design processes. We propose a standardized F-B-C-E knowledge model to formalize biological strategy representations, coupled with a BERT-based pipeline for automated inversion of biological strategies into engineering applications. To optimize strategy selection, a hybrid decision-making methodology combining VIKOR multi-criteria analysis and rank correlation is developed. The framework's functional robustness is validated via aquatic robotic system implementations, wherein three biomimetic propulsion modalities-oscillatory caudal propulsion, pulsed hydrodynamic thrust generation, and autonomous peristaltic locomotion-demonstrate quantifiable enhancements in locomotion efficiency and environmental adaptability metrics. These results underscore the robustness of the proposed inversion methodology in resolving intricate engineering problems through systematic biomimetic translation.","PeriodicalId":8907,"journal":{"name":"Biomimetics","volume":"10 6","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12191258/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144483070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0