Guizhou Normal University

ABSTRACT Climate change profoundly influences local microclimates, and plant transpiration processes are directly regulated by these microclimatic conditions. As a key topographic factor, mountain slope aspects shape local microclimatic characteristics through the redistribution of hydrothermal resources. Although plant growth and physiological processes are more directly influenced by local microclimates than by macroclimates, the differentiated responses of plant transpiration dynamics to environmental factors across different slope aspects and their underlying driving mechanisms remain unclear. This study investigates Zanthoxylum bungeanum forests on sunny and shady slopes at the same altitude in plateau gorges within a subtropical monsoon climate zone. Through in situ monitoring of sap flow (SF), local meteorological factors, soil water content (SWC) and stable isotope composition, we explored the effects of differences in microclimate and SWC on plant transpiration and water use strategies. The results showed that: (1) Water use patterns exhibited significant seasonal and slope‐related differences. During the rainy season, plants on both slopes primarily relied on shallow soil water. In the dry season, plants on the shady slope consistently utilised deep soil water (30–60 cm), whereas plants on the sunny slope rapidly shifted to using shallow and intermediate water sources following light rainfall, facing a higher risk of water source depletion. (2) During both dry and rainy seasons, SF on both slopes was primarily driven by vapour pressure deficit (VPD) and air temperature (Ta), which exerted threshold control effects on SF. These thresholds varied with slope aspect and season. Specifically, the VPD threshold during the rainy season was sunny slope (2.7 kPa) < shady slope (3.2 kPa); during the dry season, it was sunny slope (31.9°C) > shady slope (30.1°C). The Ta threshold during the rainy season was sunny slope (34.3°C) < shady slope (38.4°C); during the dry season, it was sunny slope (31.9°C) > shady slope (30.1°C). Furthermore, the stomatal conductance of plants on the shady slope was more sensitive to changes in VPD and Ta than that of plants on the sunny slope. Therefore, under drought conditions, plants on the shady slope exhibited a more robust water use strategy, with greater stability in transpiration and stomatal regulation, significantly reducing the risk of hydraulic dysfunction and demonstrating stronger drought adaptability compared to plants on the sunny slope.

Engineered interfacial layers that tune electrode energetics, suppress recombination, and enforce carrier selectivity are critical for high-efficiency organic photovoltaics (OPVs), yet current anode and cathode interface counterparts rely on distinct chemistries, increasing synthesis complexity and hindering scale-up. Here, we report a versatile molecular platform that generates both anode and cathode interface layers (AILs and CILs) from the homologous donor-acceptor-donor (carbazole-benzothiadiazole-carbazole) oligomer. Using a concise three-step route, we synthesized phosphonate-functionalized CIL (2DPeBcz) and phosphonic-acid-functionalized AIL (2DPaBcz) materials linked by a short, two-carbon alkyl spacer, which promotes dense molecular packing. Consequently, the self-assembled monolayer 2DPaBcz increases the ITO electrode work function and passivates oxygen vacancies, while its analogue 2DPeBcz based on phosphonate forms a robust interfacial dipole on Ag. Incorporating these layers in D18:BTP-eC9 devices achieved a power conversion efficiency of 19.3% and improved storage, light-soaking, and thermal stability. Electrical characterization further validated reduced trap density and balanced carrier mobility, highlighting the advantages of this versatile structural approach for scalable, high-performance OPV interfaces. Overall, this work presents a unified synthetic strategy for AIL and CIL to be derived from a single molecular backbone, simplifying material preparation while maintaining competitive OPV performance and improved device stability.

The challenge in WiFi-based cross-domain Behavior Recognition lies in the significant interference of domain-specific signals on gesture variation. However, previous methods alleviate this interference by mapping the phase from multiple domains into a common feature space. If the Doppler Frequency Shift (DFS) signal is used to dynamically supplement the phase features to achieve better generalization, it enables the model to not only explore a wider feature space but also to avoid potential degradation of gesture semantic information. Specifically, we propose a novel Salient-aware Adaptive WiFi Sensing for Cross-domain Behavior Recognition (Wi-CBR), which constructs a dual-branch self-attention module that captures temporal features from phase information reflecting dynamic path length variations while extracting kinematic features from DFS correlated with motion velocity. Moreover, we design a Saliency Guidance Module that employs group attention mechanisms to mine critical activity features and utilizes gating mechanisms to optimize information entropy, facilitating feature fusion and enabling effective interaction between salient and non-salient behavioral characteristics. Extensive experiments on two large-scale public datasets (Widar3.0 and XRF55) demonstrate the superior performance of our method in both in-domain and cross-domain scenarios.