arXivDaily arXiv每日学术速递 周一至周五更新
2606.19762 2026-06-19 q-bio.MN 新提交

Oscillations and Spatial Patterns in Large-Scale Stochastic Gene Regulatory Networks

大规模随机基因调控网络中的振荡与空间模式

Manuel Eduardo Hernández-García, Jorge Velázquez-Castro

AI总结 研究负反馈与扩散的循环基因调控网络,通过确定性和随机方法分析其稳定性,发现随机波动可诱导图灵失稳,为理解发育中的模式形成提供新视角。

Comments 16 pages, 10 figures

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AI中文摘要

基因调控网络(GRNs)是细胞生长和组织形成的基础,在发育过程中协调基因表达的时空调控。这些网络固有地受到分子噪声引起的内在波动的影响,因此分析其稳定性对于理解生物体稳健的模式形成和发育动力学至关重要。在本研究中,我们分析了具有负反馈和扩散的循环GRNs的稳定性和动力学,考虑了确定性和随机方法。在确定性情况下,系统表现出稳定性与不稳定性之间的分岔,导致无扩散时的Hopf失稳和包含扩散时的Turing-Hopf失稳。观察到空间域的离散化引入了额外的不稳定模式,从而允许更广泛的模式。基于二阶矩方法的随机框架包含了内在波动,揭示了对于小系统尺寸,即使系统在无扩散时是稳定的,波动也可以主导动力学并诱导随机Turing失稳。值得注意的是,即使所有变量具有相同的扩散速率,Turing失稳也可能出现。所开发的框架提供了一种系统的方法来分析具有扩散的高维随机系统的稳定性,从而简化了Turing和Turing-Hopf失稳的预测。这些发现有助于更深入地理解GRNs中的复杂动力学和模式形成,对细胞分化和发育等生物过程具有潜在意义。

英文摘要

Gene regulatory networks (GRNs) are fundamental to cellular growth and tissue formation, orchestrating spatially and temporally regulated gene expression during development. These networks are inherently subject to intrinsic fluctuations arising from molecular noise, making the analysis of their stability essential for understanding robust pattern formation and developmental dynamics of the organism. In this study, we analyze the stability and dynamics of cyclic GRNs with negative feedback and diffusion, considering both deterministic and stochastic approaches. In the deterministic case, the system exhibits a bifurcation between stability and instability, leading to Hopf instability in the absence of diffusion and to Turing-Hopf instability when diffusion is included. It was observed that the discretization of the spatial domain introduces additional unstable modes, enabling a wider range of patterns. The stochastic framework based on the second-moment approach, which incorporates intrinsic fluctuations, reveals that for small system sizes, fluctuations can dominate the dynamics and induce stochastic Turing instability, even when the system is stable in the absence of diffusion. Notably, Turing instabilities can emerge even when all variables have the same diffusion rate. The developed framework provides a systematic method for analyzing the stability of high-dimensional stochastic systems with diffusion, thereby simplifying the prediction of Turing and Turing-Hopf instabilities. These findings contribute to a deeper understanding of the complex dynamics and pattern formation in GRNs, with potential implications for biological processes, such as cellular differentiation and development.

2606.19739 2026-06-19 q-bio.NC 新提交

Robust probabilistic measurement of structural-functional module consistency in infant brain development

婴儿大脑发育中结构-功能模块一致性的鲁棒概率测量

Lingbin Bian, Feihong Liu, Qian Wang, Han Zhang, Dinggang Shen, the UNC/UMN Baby Connectome Project Consortium

AI总结 提出基于随机模块的概率方法,鲁棒测量婴儿大脑结构-功能模块一致性,发现0-5岁间一致性下降,初级脑区一致性更高。

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AI中文摘要

脑网络通常被划分为模块,用于分析其在神经影像学研究的群体分析中功能分离的角色。这里,我们引入脑网络中的随机模块,用于在受试者群体中对结构-功能模块一致性(SFMC)进行鲁棒的概率测量。具体而言,随机模块可被视为一个脑区在受试者间可能被分配到群体级子网络的机会,其特征为该脑区的分配概率。这种新方法在评估脑网络中的非均匀模块方面有两个优势。首先,它可以鲁棒地评估脑结构模块与功能模块之间的一致性,而两者的群体规模不必相同;其次,它能够考虑群体中模块的个体间变异性。此外,与传统的结构-功能耦合方法相比,我们的基于随机模块的方法揭示了结构与功能之间耦合的更显著下降,表明更强的发育重组。我们使用婴儿连接组项目(BCP)数据集的结果显示,SFMC在0至5岁期间下降,并且在初级脑区(如视觉区域)较高,而在更高级的认知区域(包括与注意力、控制和默认模式网络相关的区域)较低。

英文摘要

Brain network is commonly divided into modules for analyzing their functionally segregated roles for group-level analysis in neuroimaging studies. Here, we introduce stochastic modules within brain networks for a robust probabilistic measurement of structural-functional module consistency (SFMC) in a group of subjects. Specifically, a stochastic module can be regarded as the chance of a brain region across subjects potentially being assigned to a group-level sub-network, characterized as an assignment probability for this brain region. This novel method has two advantages for evaluating inhomogeneous modules in brain networks. The first is that it can robustly evaluate the consistency between brain structural and functional modules whose population sizes are not necessary the same, and the second is that it is able to take into account the inter-individual variability of the modules for the groups. Moreover, compared with the conventional structural-functional coupling approach, our stochastic module-based method reveals a more pronounced decline in the coupling between structure and function, indicating stronger developmental reorganization. Our results using the dataset from Baby Connectome Project (BCP) show that the SFMC decreases from 0 to 5 years old, and is greater in primary brain regions, such as visual areas, while lower in more advanced cognitive regions, including those related to attention, control, and default mode network.

2606.19396 2026-06-19 q-bio.QM 新提交

BioHarness: Substrate-Aware Evidence Assembly for Biomedical Question Answering across Literature, Knowledge Bases, and Biological Atlases

BioHarness:面向生物医学问答的底物感知证据组装——跨文献、知识库和生物图谱

Meng Xiao, Chuan Qin, Jinmiao Chen, Yihang Cheng, Yuanchun Zhou, Hengshu Zhu

AI总结 提出BioHarness,通过级联控制机制在文献检索、知识库和生物图谱间选择性组装证据,提升生物医学问答准确率,在19,302个问答项上得分从65.9提升至71.0。

Comments 14 Pages, 11 Figures, Keywords: biomedical question answering; retrieval-augmented generation; large language models; evidence assembly; biomedical knowledge bases; biological atlases

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AI中文摘要

动机:生物医学问答通常需要超越主题检索文献的证据,包括基因别名解析、数据库标识符标准化以及来自图谱的生物测量值。然而,现有的检索增强生成(RAG)系统通常遵循固定工作流程,缺乏明确机制来决定何时检索文本足够、何时需要经过整理的生物医学知识、或何时应调用对结构化测量值的可执行证据组装。这激发了一种底物感知的大语言模型(LLM)框架,能够跨文献、知识库和生物图谱选择性地组装足够的证据。结果:我们引入BioHarness,一种用于分阶段生物医学证据组装的LLM框架,涵盖文献检索、经过整理的生物医学知识资源以及来自图谱的结构化测量值。BioHarness首先尝试根据重排序的文献证据回答问题,并通过基于接地级联控制,仅在当前证据不确定、接地不足或底物不匹配时升级到REPL风格的证据组装。在涵盖七种答案格式的19,302个生物医学问答项上,BioHarness将最强非预言基线的综合得分从65.9提升至71.0。消融实验、案例研究和骨干扩展分析表明,这些提升源于通过重排序、实体接地和结构化测量访问修复证据-底物不匹配,而非不加区分地调用更多推理步骤、检索更多文献或依赖特定答案模型规模。

英文摘要

Motivation: Biomedical question answering often requires evidence beyond topically retrieved literature, including gene alias resolution, database identifier normalization, and atlas-derived biological measurements. However, existing retrieval-augmented generation (RAG) systems typically follow a fixed workflow and lack an explicit mechanism for deciding when retrieved text is sufficient, when curated biomedical knowledge is required, or when executable evidence assembly over structured measurements should be invoked. This motivates a substrate-aware large language model (LLM) harness that selectively assembles sufficient evidence across literature, knowledge bases, and biological atlases. Results: We introduce BioHarness, an LLM harness for staged biomedical evidence assembly across literature retrieval, curated biomedical knowledge resources, and atlas-derived structured measurements. BioHarness first attempts to answer from reranked literature evidence and escalates through grounded cascade control to REPL-style evidence assembly only when the current evidence is uncertain, weakly grounded, or substrate-mismatched. Across 19,302 biomedical QA items spanning seven answer formats, BioHarness improves the pooled score from 65.9 to 71.0 over the strongest non-oracle baseline. Ablations, case studies, and backbone-scaling analyses show that these gains arise from repairing evidence-substrate mismatches through reranking, entity grounding, and structured measurement access, rather than from indiscriminately invoking more reasoning steps, retrieving additional literature, or relying on a particular answer-model scale.

2606.20315 2026-06-19 q-bio.GN cs.CR 新提交

bioETH-Beacon: A Confidential On-Chain Genomic Beacon with Encrypted Counts, Filters, and Bounded Noise over a Fully Homomorphic EVM

bioETH-Beacon: 基于全同态EVM的机密基因组信标,支持加密计数、过滤和有界噪声

Christos Galanopoulos, Kimon Antonios Provatas, Ilias Georgakopoulos-Soares

AI总结 提出基于全同态EVM的智能合约原型bioETH-Beacon,实现加密基因组信标查询,通过加密计数、有界噪声和访问控制抵御成员推理攻击,并优化查询成本。

Comments 11 pages, 6 figures, 8 tables. Research prototype for privacy-preserving genomics using Fully Homomorphic Encryption (FHE) on blockchain (fhEVM)

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AI中文摘要

全球基因组学与健康联盟(GA4GH)Beacon协议允许研究人员查询某个基因组变异是否在参与队列中被观察到,并返回聚合的变异级计数。随着Beacon网络的发展,两个隐私风险依然存在:宿主机构可以看到明文查询,而重复的罕见变异查询可能支持成员推理攻击。我们提出了bioETH-Beacon,一个智能合约原型,它在全同态以太坊虚拟机(fhEVM)上对加密数据执行Beacon“聚合计数”查询。医院上传加密的标记计数条目,授权研究人员提交加密的标记查询,合约返回加密答案,通过链下密钥管理服务仅释放给合约链上ACL中指定的请求者。该设计组织为一个3x4的层级-查询族网格,涵盖基因型、性别、年龄和表型查询,层级在更强的机密性和更低的查询成本之间进行权衡。对于基因型路径,原型可以添加链上有界噪声以减轻探测攻击。基于多基因评分(PGS)目录的合成面板实验显示了预期的扩展行为,并证明当公共标记存在是可接受的权衡时,预聚合可以显著降低查询gas成本。总体而言,bioETH-Beacon提供了一个无需可信计算评估者的机密Beacon式基因组查询研究原型。

英文摘要

The Global Alliance for Genomics and Health (GA4GH) Beacon protocol lets researchers ask whether a genomic variant has been observed in a participating cohort and receive aggregate variant-level counts. As Beacon networks grow, two privacy risks remain: host institutions can see plaintext queries, and repeated rare-variant queries can support membership-inference attacks. We present bioETH-Beacon, a smart-contract prototype that runs the Beacon "aggregate count" query over encrypted data on a fully homomorphic Ethereum Virtual Machine (fhEVM). Hospitals upload encrypted marker-count entries, authorized researchers submit encrypted marker queries, and the contract returns an encrypted answer that is released, via an off-chain key-management service, only to the requester named in the contract's on-chain ACL. The design is organized as a 3x4 tier-by-query-family grid spanning genotype, sex, age, and phenotype queries, with tiers that trade stronger confidentiality for lower query cost. For genotype paths, the prototype can add bounded on-chain noise to mitigate probing attacks. Experiments on synthetic panels derived from a Polygenic Score (PGS) catalog show the expected scaling behavior and demonstrate that pre-aggregation can substantially reduce query gas when public marker presence is an acceptable trade-off. Overall, bioETH-Beacon provides a research prototype for confidential Beacon-style genomic querying without a trusted compute evaluator.

2606.20223 2026-06-19 cs.CV q-bio.QM 新提交

DeepForestVisionV2: Ecology-Driven Taxonomy Expansion for Camera-Trap Monitoring in African Tropical Forests

DeepForestVisionV2:面向非洲热带森林相机监测的生态驱动分类扩展

Hugo Magaldi, Theau d'Audiffret, Etienne Francois Akomo-Okoue, Bala Amarasekaran, Naomi Anderson, Claire Auger, Noemie Cappelle, Daniel Cornelis, Raphael Cornette, Tobias Deschner, Gabriel Dubus, Davy Fonteyn, Rosa M. Garriga, Jennifer Hatlauf, Innocent Kasekendi, Raymond Katumba, Aram Kazandjian, Alfred Ngomanda, Stephan Ntie, Simone Pika, Xavier Rufray, Harold Rugonge, John Justice Tibesigwa, Peter van Lunteren, Hadrien Vanthomme, Joeri A. Zwerts, Sabrina Krief

发表机构 * UMR7206 Eco-Anthropologie, MNHN(UMR7206 生态人类学,法国国家自然历史博物馆) One Forest Vision initiative(One Forest Vision 倡议) Sebitoli Chimpanzee Project(塞比托利黑猩猩项目) Centre National de la Recherche Scientifique et Technologique(国家科学技术研究中心) Institut de Recherche en Ecologie Tropicale(热带生态研究所) Tacugama Chimpanzee Sanctuary(塔库加马黑猩猩保护区) Biotope(Biotope 公司) CIRAD(法国农业发展国际合作研究中心) Max Planck Institute for Evolutionary Anthropology(马克斯·普朗克进化人类学研究所) BOKU University(维也纳自然资源与生命科学大学) Agence Nationale des Parcs Nationaux du Gabon(加蓬国家公园管理局) Uganda Wildlife Authority(乌干达野生动物管理局) Addax Data Science(Addax 数据科学公司) Utrecht University(乌得勒支大学)

AI总结 针对非洲热带森林相机监测中生态梯度(垂直分层、场景开放度、人为界面)导致原35类分类过粗的问题,提出扩展至64类的DeepForestVisionV2,在保持离线工作流的同时提升野外实用性。

Comments Accepted at ICPR 2026 - Computer Vision for Biodiversity Monitoring and Conservation Workshop

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AI中文摘要

非洲热带森林中的相机监测正从封闭冠层内部扩展到河岸、空地和公园边缘。在现有的非洲森林相机分类开放工具中,DeepForestVision是唯一提供照片和视频匹配离线工作流的工具,先前研究表明其在可比基准上优于其他基线。然而,它专为封闭冠层、地面森林内部设计,使用35类预测空间,当部署遇到树栖灵长类、鸟类、半水生类群或家畜等人为混杂因素时,该空间变得过于粗糙。我们提出DeepForestVisionV2,这是一个从35类扩展到64类预测空间(61个动物类加上人类、车辆和空白)的生态驱动扩展,旨在解决三个反复出现的部署梯度:垂直分层、场景开放度和人为界面。DeepForestVisionV2保留相同的离线工作流,并在来自多国非洲热带森林项目的1,535,010张照片和243,354个视频上训练。评估结合了一个跨国家裁剪照片验证集(用于评估跨站点和相机设置的鲁棒性)和三个涵盖目标梯度的留出乌干达视频基准。在验证集上,DeepForestVisionV2达到0.86准确率、0.82宏F1和0.81平衡准确率。在部署基准上,尽管分类任务更困难,它仍保持或提高了基线准确率,同时将识别的类群数量从森林内部视频的22个增加到29个,河岸视频从4个增加到9个。在公园边缘用例中,它将准确率从0.62提高到0.86,并将误报从11次减少到0次。这些结果表明,DeepForestVisionV2在保持跨站点、栖息地和相机设置鲁棒性的同时,显著提高了野外实用性。

英文摘要

Camera-trap monitoring in African tropical forests increasingly extends beyond closed-canopy interiors to riverbanks, clearings, and park edges. Among available open tools for African forest camera-trap classification, DeepForestVision is the only one providing a matched offline workflow for both photographs and videos, and previous work showed that it outperformed other available baselines on a comparable benchmark. However, it was designed for closed-canopy, ground-level forest interiors and uses a 35-class prediction space that becomes too coarse when deployments encounter arboreal primates, birds, semi-aquatic taxa, or human-associated confounders such as livestock. We present DeepForestVisionV2, an ecology-driven expansion from 35 to 64 prediction classes (61 animal classes plus human, vehicle, and blank) designed to address three recurrent deployment gradients: vertical stratification, scene openness, and anthropogenic interfaces. DeepForestVisionV2 retains the same offline workflow and is trained on 1,535,010 photographs and 243,354 videos from multi-country African tropical-forest projects. Evaluation combines a cross-country cropped-photo validation set, used to assess robustness across sites and camera-trap settings, with three held-out Uganda video benchmarks spanning the targeted gradients. On the validation set, DeepForestVisionV2 reaches 0.86 accuracy, 0.82 macro-F1, and 0.81 balanced accuracy. On the deployment benchmarks, it preserves or improves baseline accuracy despite its harder classification task, while increasing the number of identified taxa from 22 to 29 in forest-interior videos and from 4 to 9 at riverbanks. In the park-edge use case, it raises accuracy from 0.62 to 0.86 and reduces false alarms from 11 to 0. These results show that DeepForestVisionV2 materially improves field utility while preserving robustness across sites, habitats, and camera-trap settings.

2606.20164 2026-06-19 cs.CL cs.AI cs.LG q-bio.QM 新提交

MedRLM: Recursive Multimodal Health Intelligence for Long-Context Clinical Reasoning, Sensor-Guided Screening, Evidence-Grounded Decision Support, and Community-to-Tertiary Referral Optimization

MedRLM:用于长上下文临床推理、传感器引导筛查、证据支持决策及社区到三级转诊优化的递归多模态健康智能

Aueaphum Aueawatthanaphisut

发表机构 * School of Information, Computer Communication Technology Sirindhorn International Institute of Technology, Thammasat University Pathum Thani, Thailand 1

AI总结 提出MedRLM递归多模态健康智能框架,通过递归检查、分解、检索、验证和合成患者信息,协调多个专业代理并引入临床证据图记忆,实现长上下文临床推理和传感器引导筛查。

Comments 9 pages, 3 figures, 3 tables, 1 Algorithm, 29 equations

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AI中文摘要

现实世界的临床决策支持需要对异质性和纵向的患者信息进行推理,而不是回答孤立的医学问题。然而,当前的医学大语言模型和检索增强生成系统通常依赖单步提示或检索,当临床证据分布在长电子健康记录、医学图像、传感器流、指南和转诊约束中时,这可能变得脆弱。本文提出MedRLM,一个用于长上下文临床推理、传感器引导筛查和社区到三级转诊支持的递归多模态健康智能框架。MedRLM不是将所有患者信息压缩到一个提示中,而是将患者病例视为一个外部临床环境,可以递归地检查、分解、检索、验证和综合。该框架协调了专门用于临床文本、纵向EHR、医学影像、生理传感器信号、指南检索、不确定性审计和转诊规划的代理。它进一步引入了临床证据图记忆,将患者特定的观察结果与检索到的证据、标准化定义、传感器衍生的生物标志物和转诊标准连接起来。传感器引导的递归触发机制在检测到异常生理或行为模式时激活更深层次的推理,而不确定性门控细化支持临床医生对高风险或低置信度病例的审查。我们还概述了一个使用公共和经认证的临床数据集(涵盖EHR、放射学、ECG、ICU时间序列和转诊代理结果)的真实数据评估设计。MedRLM旨在将医学AI从静态问答转向可审计、多模态和流程感知的临床决策支持。

英文摘要

Real-world clinical decision support requires reasoning over heterogeneous and longitudinal patient information rather than answering isolated medical questions. However, current medical large language models and retrieval-augmented generation systems often rely on single-step prompting or retrieval, which can be fragile when clinical evidence is distributed across long electronic health records, medical images, sensor streams, guidelines, and referral constraints. This paper proposes MedRLM, a Recursive Multimodal Health Intelligence framework for long-context clinical reasoning, sensor-guided screening, and community-to-tertiary referral support. Instead of compressing all patient information into one prompt, MedRLM treats the patient case as an external clinical environment that can be recursively inspected, decomposed, retrieved, verified, and synthesized. The framework coordinates specialized agents for clinical text, longitudinal EHR, medical imaging, physiological sensor signals, guideline retrieval, uncertainty auditing, and referral planning. It further introduces a Clinical Evidence Graph Memory to connect patient-specific observations with retrieved evidence, standardized definitions, sensor-derived biomarkers, and referral criteria. A sensor-guided recursive triggering mechanism activates deeper reasoning when abnormal physiological or behavioral patterns are detected, while uncertainty-gated refinement supports clinician review for high-risk or low-confidence cases. We also outline a real-data evaluation design using public and credentialed clinical datasets spanning EHR, radiology, ECG, ICU time series, and referral-proxy outcomes. MedRLM aims to move medical AI from static question answering toward auditable, multimodal, and workflow-aware clinical decision support.

2606.20096 2026-06-19 cs.CG q-bio.NC 新提交

Quadratic Forms for Measuring Geometric Trees in 3-dimensional Space

用于测量三维空间中几何树的二次型

Yossi Bokor Bleile, Emanuele Cortinovis, Herbert Edelsbrunner, Shota Uka

AI总结 提出使用二次型测量几何树的方向分布,并引入基于Fisher度量的六边形图模型进行可视化和统计分析。

Comments 16 pages, 6 figures

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AI中文摘要

树状结构出现在许多科学领域,其形状有助于理解它们驱动或产生的潜在过程。通过将这些结构视为$\mathbb{R}^3$中的几何图,我们可以利用计算几何和拓扑学的工具来研究它们。在本文中,我们采用二次型理论来测量几何图的方向分布,并引入六边形图模型——配备基于标准三角形上Fisher度量的度量——用于可视化、测量和收集统计数据。

英文摘要

Tree-like structures appear in many areas of science, and their shapes can help understand the underlying processes they drive or that give rise to them. By thinking of these structures as geometric graphs in $\mathbb{R}^3$, we gain access to tools from computational geometry and topology to study them. In this paper, we adopt the theory of quadratic forms to measure the directional spread of geometric graphs, and we introduce the hexplot model -- equipped with a metric derived from the Fisher metric on the standard triangle -- to visualize, measure, and collect statistics.

2606.19405 2026-06-19 q-bio.QM math.DS q-bio.PE 新提交

Multi-type branching inference on contact trees with application to COVID-19

接触树上的多类型分支推断及其在COVID-19中的应用

Augustine Okolie, Johannes Müller, Eno Akarawakc, Isaac Ajiboye

AI总结 提出一种直接作用于接触树上传播树的似然框架,通过多类型分支过程考虑接触度异质性,从部分解析的传播树中推断流行病学参数,并在COVID-19接触追踪数据中验证。

Comments 26 pages, 8 Figures

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AI中文摘要

从传播树推断流行病学参数对于理解传染病动态至关重要。现有的基于树的似然方法,包括最初应用于系统动力学环境中的多类型出生-死亡模型,提供了强大的工具,但大多数假设均匀混合,很少捕捉当个体感染更多接触者时传播潜力的变化。在这项工作中,我们开发了一个直接作用于传播树的似然框架,其中节点是个体,边是报告的传播事件,不涉及序列数据。我们推导了一个在有根接触树上的随机SIR过程的似然,其中每个感染个体由有效接触总数和已感染的下游接触数来刻画。我们得到了一个分支完全未被观察到的概率以及它产生一个处于给定状态的观察(采样)末端的概率密度的闭式常微分方程。对于已知末端状态的有根接触树,可以评估得到的似然,并且我们通过将内部分支时间视为潜在变量,将其扩展到部分解析的树。在模拟爆发上的验证确认了准确的参数恢复和良好校准的不确定性。应用于印度卡纳塔克邦的经验COVID-19接触追踪数据,展示了该框架在实际流行病学环境中的实用性。通过在多类型分支似然中纳入接触度异质性,我们的工作为从完全或部分解析的传播树推断传播动态和接触结构提供了一个原则性的基线,补充而非依赖于基于序列的系统动力学推断。

英文摘要

Inferring epidemiological parameters from transmission trees is essential for understanding infectious disease dynamics. Existing tree-based likelihood methods, including the multi-type birth-death models originally applied in phylodynamic settings, provide powerful tools, but most assume homogeneous mixing and rarely capture how transmission potential changes as an individual infects more of their contacts. In this work, we develop a likelihood framework that operates directly on transmission trees, in which nodes are individuals and edges are reported transmission events, with no sequence data involved. We derive a likelihood for a stochastic SIR process on a rooted contact tree in which each infected individual is characterised by the total number of effective contacts, and the number of already infected downstream contacts. We obtain closed-form ordinary differential equations for the probability that a clade goes entirely unobserved and for the probability density that it produces an observed (sampled) tip in a given state. The resulting likelihood can be evaluated for a rooted contact tree with known tip states, and we extend it to partially resolved trees by treating internal branching times as latent variables. Validation on simulated outbreaks confirms accurate parameter recovery and well calibrated uncertainty. Application to empirical COVID-19 contact-tracing data from Karnataka, India, demonstrates the framework's utility for real epidemiological settings. By incorporating contact-degree heterogeneity in a multi-type branching likelihood, our work provides a principled baseline for inferring both transmission dynamics and contact structure from fully or partially resolved transmission trees, complementing rather than relying on sequence-based phylodynamic inference

2606.20489 2026-06-19 q-bio.PE nlin.CG physics.bio-ph stat.AP 新提交

West Nile virus outbreak in Italy modelled with the quantum Game of Life

意大利西尼罗病毒疫情用量子生命游戏建模

Andrea Fontana, Simone Tambascia, Ciro Di Carluccio, Andrea Esposito, Bernardo Spagnolo, Andrea M. Chiariello

AI总结 使用量子生命游戏细胞自动机模型模拟2025年夏季意大利西尼罗病毒传播,通过优化蚊子出生和移除率,准确拟合局部和区域平均累计感染曲线,并评估环境变化的影响。

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AI中文摘要

近年来,意大利观察到西尼罗病毒(WNV)异常高传播,特别是在拉齐奥南部、坎帕尼亚和威尼托地区感染高峰显著。WNV的主要病媒是库蚊,通过叮咬传播人类感染。本文通过基于量子版本的生命游戏(GOL)细胞自动机模型的计算方法,研究2025年夏季意大利西尼罗热疫情的扩散。具体而言,人类动力学根据GOL规则演化,而病媒(即蚊子)的随机动力学及其与人类的相互作用同时发生。我们表明,该模型在局部和平均区域水平上以高精度拟合累计感染个体曲线,仅需优化蚊子出生率和移除率参数。此外,利用模型的灵活性,我们表明模型参数值的变化阐明了系统对环境变化的响应。例如,我们量化了蚊子传播控制措施或由于气候和生态变化导致的蚊子突然增加的影响。总体而言,我们提供了意大利WNV感染传播的一般定量描述,可作为测试不同环境情景的支持工具,并有助于决策者制定监测病媒动力学和控制病毒传播的策略。

英文摘要

In the last years, an anomalously high spreading of West Nile virus (WNV) has been observed in Italy, with particularly high peaks of infections in southern Lazio, Campania and Veneto regions. The main disease vector for WNV is represented by Culex pipiens mosquitoes, which spread human infections through their bites. Here, we investigate WNV fever epidemic diffusion during summer season 2025 in Italy through a computational approach based on a quantum version of the Game of Life (GOL) cellular automaton model. Specifically, human dynamics evolves according to the GOL rules, while stochastic dynamics of disease vectors, i.e., mosquitoes, as well as their interaction with humans, simultaneously occur. We show that this model fits the curves of cumulative infected individuals with high accuracy, either at local and average-regional level, with only optimization of mosquito birth and removal rates parameters. Furthermore, leveraging model flexibility, we show that changes in model parameters values elucidate system response to environmental variations. For instance, we quantify, e.g., the impact of mosquito spreading containment measures or sudden mosquito increasing abundance due to climatic and ecological changes. Overall, we provide a general, quantitative description of WNV infection spreading in Italy which could represent a supportive tool to test different environmental scenarios and could be useful to devise strategies for decision makers to monitor disease vector dynamics and to control consequent virus diffusion.

2606.20345 2026-06-19 nlin.AO q-bio.NC 新提交

Synchronization modes in bipartite oscillator networks

二分振荡器网络中的同步模式

Pau Pomés, Bastian Pietras, Ernest Montbrió

AI总结 研究二分网络上Kuramoto-Sakaguchi模型的集体动力学,发现从完全同步到部分同步的连续和非连续转变,部分同步态表现为自组织准周期行为。

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AI中文摘要

神经元系统中的集体振荡通常源于兴奋性和抑制性群体之间的相互作用,而非单个群体内的循环耦合。受此类系统中强同步和部分同步状态共存的启发,我们研究了二分网络上的Kuramoto-Sakaguchi模型。尽管结构简单,该模型展现出丰富的集体动力学,包括从完全同步到部分同步(PS)的连续和非连续转变。在PS状态下,全局振荡无法带动其中一个群体,该群体的振荡器表现出准周期动力学,其平均频率可能显著偏离全局场的频率,正如在神经元网络中观察到的那样。我们表明,这种PS状态构成了自组织准周期性的一个例子,尽管其全局耦合是纯线性的,但在经典的Kuramoto-Sakaguchi模型中出现了这种自组织准周期性。

英文摘要

Collective oscillations in neuronal systems often arise from interactions between excitatory and inhibitory populations rather than from recurrent coupling within a single ensemble. Motivated by the coexistence of strongly and partially synchronized regimes in such systems, we study the Kuramoto Sakaguchi model on a bipartite network. Despite its minimal structure, the model exhibits rich collective dynamics, including both continuous and discontinuous transitions from full synchrony to partial synchrony (PS). In the PS regime, global oscillations fail to entrain one of the two populations, whose oscillators display quasiperiodic dynamics with an average frequency that can significantly deviate from that of the global field, as observed in neuronal networks. We show that this PS state constitutes an example of self-organized quasiperiodicity, arising here in the canonical Kuramoto Sakaguchi model despite its purely linear global coupling.

2606.16803 2026-06-19 q-bio.MN q-bio.SC 新提交

Cell Division Changes Fate Decisions in a Genetic Toggle Switch

细胞分裂改变遗传开关中的命运决定

Charli Austin, Nikola Popovic, Ramon Grima

AI总结 本研究通过分析布尔型遗传开关模型,发现细胞分裂可将相同初始条件的轨迹导向不同稳定态,并定义了忽略分裂时命运预测错误的区域,表明分裂可重塑多稳态调控网络的命运边界。

Comments 16 pages;7 figures. Includes new Figure A.2 comparing the separatrices of the classical and Boolean toggle switches, with and without cell division. Two Appendices (previously H and I in the previous version) integrated into Appendix E for clarity

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AI中文摘要

基因调控网络通过多稳态动力学控制细胞命运决定。遗传开关是此类行为的经典模型;然而,细胞分裂对其动力学的影响仍知之甚少。我们推导了有无分裂的简化布尔型开关的解析分界线。我们证明,分裂可以将具有相同初始条件的轨迹重定向到相反的稳定态,并定义了一个不一致区域,在该区域中,如果忽略分裂,则命运预测错误。我们的结果表明,分裂可以从根本上重塑多稳态调控网络中的命运边界。

英文摘要

Gene regulatory networks govern cellular fate decisions through multistable dynamics. The genetic toggle switch is a canonical model of such behaviour; yet, the impact of cell division on its dynamics remains poorly understood. We derive analytical separatrices for a simplified Boolean toggle switch with and without division. We show that division can redirect trajectories with identical initial conditions to opposing stable states, and we define a region of disagreement where fate decisions are predicted incorrectly if division is neglected. Our results imply that division can fundamentally reshape fate boundaries in multistable regulatory networks.

2606.14510 2026-06-19 cs.LG q-bio.BM 新提交

PepALD: Macrocyclic Peptide Generation via Autoregressive Latent Diffusion

PepALD: 通过自回归潜在扩散生成大环肽

Junming Zhang, Siyu Yi, Wei Ju, Zhonghui Gu

发表机构 * College of Computer Science, Sichuan University(四川大学计算机科学学院) School of Mathematics, Sichuan University(四川大学数学学院) School of Artificial Intelligence, Sichuan University(四川大学人工智能学院) Lingang Laboratory(临港实验室)

AI总结 提出PepALD模型,结合自回归潜在扩散与化学嵌入,实现从头设计大环肽,并利用偏好优化提升亲和力,在生成质量和奖励优化上优于基线。

Comments 18 pages, 5 figures, 3 tables

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AI中文摘要

大环肽是细胞内靶点的有前景的治疗候选物,但其设计需要同时控制非天然单体化学、环拓扑、膜通透性和靶点结合。现有的SMILES或HELM字符串生成模型要么在长原子级序列空间中操作,要么将单体视为具有有限化学基础符号化令牌。我们引入了PepALD,一个用于从头生成大环肽的自回归潜在扩散(ALD)基础模型。该模型使用结构化化学嵌入表示HELM单体,通过在化学信息潜在空间中的上下文条件扩散生成每个残基,在自回归生成过程中预测R基团感知的环闭合,并使用胜者保护的扩散自适应偏好优化将去噪器与亲和力奖励对齐。体外实验表明,PepALD在生成质量和奖励优化性能上优于代表性肽生成基线。

英文摘要

Macrocyclic peptides are promising therapeutic candidates for intracellular targets, but their design requires simultaneous control over non-natural monomer chemistry, ring topology, membrane permeability, and target binding. Existing SMILES- or HELM-string generative models either operate in long atom-level sequence spaces or treat monomers as symbolic tokens with limited chemical grounding. We introduce PepALD, an Autoregressive Latent Diffusion (ALD) foundation model for \textit{de novo} macrocyclic peptide generation. The model represents HELM monomers with structured chemical embeddings, generates each residue through context-conditioned diffusion in chemically informed latent space, predicts R-group-aware ring closures during autoregressive generation, and aligns the denoiser to affinity rewards using winner-protected diffusion-adapted preference optimization. In silico experiments demonstrate PepALD's generation quality and reward-optimization performance against representative peptide generation baselines.

2503.04507 2026-06-19 q-bio.QM cs.CG cs.LG 交叉投稿

The Morse Transform for Discrete Shape Analysis

离散形状分析的Morse变换

Alexander M. Tanaka, Aras T. Asaad, Richard Cooper, Vidit Nanda

AI总结 提出一种基于定向分段线性Morse理论的拓扑变换,通过记录多个高度函数下的临界点来量化嵌入对象的几何形状,生成的特征向量在配体虚拟筛选中取得最优平均AUROC。

Comments 37 pages, 3 main figures, 2 main tables, 12 appendix figures and 4 appendix tables

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AI中文摘要

物体的几何形状在调节其与物理世界的相互作用中起着至关重要的作用。然而,为了统计推断或分类任务的目的,用数值描述几何信息仍然困难。在这里,我们引入了一种新的拓扑变换,它利用定向分段线性Morse理论,通过编录多个高度函数下的临界点来量化嵌入对象的几何形状。该Morse变换的输出记录了表征底层形状的临界点的高度和局部拓扑类型(峰、谷或鞍点),保留了比欧拉特征变换更精细的信息,同时自然优先考虑形状的最外层区域。关键的是,该输出可以进一步压缩为丰富而紧凑的特征向量。我们将Morse特征向量作为配体虚拟筛选(LBVS)的描述符进行基准测试,这本质上依赖于分子的形状。在常见的梯度提升树分类流程下,与其他拓扑变换描述符和标准基于形状的LBVS描述符相比,Morse描述符实现了最高的平均AUROC。

英文摘要

The geometry of an object plays a vital role in modulating its interactions with the physical world. It nevertheless remains difficult to describe geometric information numerically for the purposes of statistical inference or classification tasks. Here, we introduce a new topological transform which leverages directional piecewise-linear Morse theory to quantify the geometry of an embedded object by cataloguing critical points across multiple height-functions. The output of this Morse transform records both the heights and the local topological type (peak, trough or saddle) of the critical points that characterise the underlying shape, retaining finer information than the Euler characteristic transform whilst naturally prioritising a shape's outermost regions. Crucially, this output can be further compressed into a rich but compact feature vector. We benchmark the Morse feature vector as a descriptor for ligand-based virtual screening (LBVS), which intrinsically depends on the shape of molecules. Under a common gradient-boosted tree classification pipeline, Morse descriptors achieve the highest mean AUROC when compared to other topological transform descriptors and to standard shape-based LBVS descriptors.

1812.03321 2026-06-19 q-bio.QM

Isolating phyllotactic patterns embedded in the secondary growth of sweet cherry (Prunus avium L.) using magnetic resonance imaging

Mitchell Eithun, Daniel H. Chitwood, James Larson, Gregory Lang, Elizabeth Munch

Comments Code: https://github.com/eithun/cherry-phyllotaxy

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英文摘要

Epicormic branches arise from dormant buds patterned during the growth of previous years. Dormant epicormic buds remain on the surface of trees, pushed outward from the pith during secondary growth, but maintaining vascular connections. Epicormic buds can be reactivated, either through natural processes or intentionally, to rejuvenate orchards and control tree architecture. Because epicormic structures are embedded within secondary growth, tomographic approaches are a useful method to study them and understand their development. We apply techniques from image processing to determine the locations of epicormic vascular traces embedded within secondary growth of sweet cherry (Prunus avium L.), revealing the juvenile phyllotactic pattern in the trunk of an adult tree. Techniques include breadth-first search to find the pith of the tree, edge detection to approximate the radius, and a conversion to polar coordinates to threshold and segment phyllotactic features. Intensity values from Magnetic Resonance Imaging (MRI) of the trunk are projected onto the surface of a perfect cylinder to find the locations of traces in the "boundary image". Mathematical phyllotaxy provides a means to capture the patterns in the boundary image by modeling phyllotactic parameters. Our cherry tree specimen has the conspicuous parastichy pair $(2,3)$, phyllotactic fraction 2/5, and divergence angle of approximately 143 degrees. The methods described not only provide a framework to study phyllotaxy, but for image processing of volumetric image data in plants. Our results have practical implications for orchard rejuvenation and directed approaches to influence tree architecture. The study of epicormic structures, which are hidden within secondary growth, using tomographic methods also opens the possibility of studying the genetic and environmental basis of such structures.

1802.04677 2026-06-19 math.AT math.DS q-bio.QM

Evolutionary homology on coupled dynamical systems

Zixuan Cang, Elizabeth Munch, Guo-Wei Wei

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英文摘要

Time dependence is a universal phenomenon in nature, and a variety of mathematical models in terms of dynamical systems have been developed to understand the time-dependent behavior of real-world problems. Originally constructed to analyze the topological persistence over spatial scales, persistent homology has rarely been devised for time evolution. We propose the use of a new filtration function for persistent homology which takes as input the adjacent oscillator trajectories of a dynamical system. We also regulate the dynamical system by a weighted graph Laplacian matrix derived from the network of interest, which embeds the topological connectivity of the network into the dynamical system. The resulting topological signatures, which we call evolutionary homology (EH) barcodes, reveal the topology-function relationship of the network and thus give rise to the quantitative analysis of nodal properties. The proposed EH is applied to protein residue networks for protein thermal fluctuation analysis, rendering the most accurate B-factor prediction of a set of 364 proteins. This work extends the utility of dynamical systems to the quantitative modeling and analysis of realistic physical systems.