Evidence-Based Medical Question Answering (EB-MQA) aims to provide accurate and verifiable responses to support clinical decisions. To retrieve evidence from general medical knowledge graphs (KGs), existing knowledge augmentation methods use semantic similarity or dynamic sampling for entity matching and agentic expansion or subgraph scoring for path retrieval. These approaches can introduce entity-level noise from irrelevant or generic entities and path-level noise from redundant or spurious reasoning chains. We propose ToToFilter, a train-free topic- and topology-aware noise filtering framework with Topic-Aware Entity Localization for query-relevant entity anchoring and Topology-Aware Path Filtering for path selection based on semantic consistency, structural compactness, and information specificity. Across four MQA benchmarks, ToToFilter achieves average accuracy gains of 2.30 and 1.22 percentage points over DALK on Llama3.1-8B and Qwen2.5-7B, with maximum gains of 2.60 and 2.78 points. On PrimeKGQA, it improves answer recall and triple recall by up to 8.81 and 19.70 percentage points. Further analyses verify the effectiveness of the proposed two-level filtering framework.

Empathetic response generation aims to generate empathetic responses by understanding the speaker’s emotional feelings from the language of dialogue. Recent methods capture emotional words in the language of communicators and construct them as static vectors to perceive nuanced emotions. However, linguistic research has shown that emotional words in language are dynamic and have correlations with other grammar semantic roles, i.e., words with semantic meanings, in grammar. Previous methods overlook these two characteristics, which easily lead to misunderstandings of emotions and neglect of key semantics. To address this issue, we propose a dynamical Emotion-Semantic Correlation Model (ESCM) for empathetic dialogue generation tasks. ESCM constructs dynamic emotion-semantic vectors through the interaction of context and emotions. We introduce dependency trees to reflect the correlations between emotions and semantics. Based on dynamic emotion-semantic vectors and dependency trees, we propose a dynamic correlation graph convolutional network to guide the model in learning context meanings in dialogue and generating empathetic responses. Experimental results on the EMPATHETIC-DIALOGUES dataset show that ESCM understands semantics and emotions more accurately and expresses fluent and informative empathetic responses. Our analysis results also indicate that the correlations between emotions and semantics are frequently used in dialogues, which is of great significance for empathetic perception and expression.