The effects of test on associative memory depend on semantic relevancy levels: evidence of event-related potentials.

This study aims to investigate how the level of semantic relevance influences the effects of test on associative memory through bottom-up cognitive processes. This study manipulated the levels of semantic relevancy using synonym and nonsynonym pairs in a three-phase testing effect paradigm (an initial encoding phase, a cued-recall test as retrieval practice, and a final test phase) to explore the effects of testing effect and semantic relevancy on associative recognition by bottom-up processes using the event-related potential (ERP). The behavioral results suggested that the test practice (relative to the restudy) significantly facilitated memory retrieval in high semantic relevancy pairs during the final test phase.

Mistletoes have higher hydraulic safety but lower efficiency in xylem traits than their hosts.

Both mistletoes and their hosts are challenged by increasing drought, highlighting the necessity of understanding their comparative hydraulic properties. The high transpiration of mistletoes requires efficient water transport, while high xylem tensions demand strong embolism resistance, representing a hydraulic paradox. This study, conducted across four environments with different aridity indices in Yunnan, China, examined the xylem traits of 119 mistletoe-host species pairs.

Linkages among stem xylem transport, biomechanics, and storage in lianas and trees across three contrasting environments.

Premise: Stem xylem transports water and nutrients, mechanically supports aboveground tissues, and stores water and nonstructural carbohydrates. These three functions are associated with three types of cells-vessel, fiber, and parenchyma, respectively.

Methods: We measured stem theoretical hydraulic conductivity (K), modulus of elasticity (MOE), tissue water content, starch, soluble sugars, cellulose, and xylem anatomical traits in 15 liana and 16 tree species across three contrasting sites in Southwest China.

Convergent relationships between flower economics and hydraulic traits across aquatic and terrestrial herbaceous plants.

Maintaining open flowers is critical for successful pollination and depends on long-term water and carbon balance. Yet the relationship between how flower hydraulic traits are coordinated in different habitats is poorly understood. Here, we hypothesize that the coordination and trade-offs between floral hydraulics and economics traits are independent of environmental conditions.

Vessel dimorphism and wood traits in lianas and trees among three contrasting environments.

Premise: Determining how xylem vessel diameters vary among plants and across environments gives insights into different water-use strategies among species and ultimately their distributions. Here, we tested the vessel dimorphism hypothesis that the simultaneous occurrence of many narrow and a few wide vessels gives lianas an advantage over trees in seasonally dry environments.

Methods: We measured the diameters of 13,958 vessels from 15 liana species and 10,430 vessels from 16 tree species in a tropical seasonal rainforest, savanna, and subtropical evergreen broadleaved forest.

Physiological response and photosynthetic recovery to an extreme drought: Evidence from plants in a dry-hot valley savanna of Southwest China.

The frequency of extreme drought events has been rising worldwide, but due to its unpredictability, how plants will respond remains poorly understood. Here, we aimed to characterize how the hydraulics and photosynthesis of savanna plants respond to extreme drought, and tested whether they can subsequently recover photosynthesis after drought. There was an extreme drought in 2019 in Southwest (SW) China.

You are what you eat: nutrient and water relations between mistletoes and hosts.

Mistletoes play important roles in biogeochemical cycles. Although many studies have compared nutrient concentrations between mistletoes and their hosts, no general patterns have been found and the nutrient uptake mechanisms in mistletoes have not been fully resolved. To address the water and nutrient relations in mistletoes compared with their hosts, we measured 11 nutrient elements, two isotope ratios and two leaf morphological traits for 11 mistletoe and 104 host species from four sites across a large environmental gradient in southwest China.

Convergence in phosphorus constraints to photosynthesis in forests around the world.

Tropical forests take up more carbon (C) from the atmosphere per annum by photosynthesis than any other type of vegetation. Phosphorus (P) limitations to C uptake are paramount for tropical and subtropical forests around the globe. Yet the generality of photosynthesis-P relationships underlying these limitations are in question, and hence are not represented well in terrestrial biosphere models.

Higher water and nutrient use efficiencies in savanna than in rainforest lianas result in no difference in photosynthesis.

Differences in traits between lianas and trees in tropical forests have been studied extensively; however, few have compared the ecological strategies of lianas from different habitats. Here, we measured 25 leaf and stem traits concerning leaf anatomy, morphology, physiology and stem hydraulics for 17 liana species from a tropical seasonal rainforest and for 19 liana species from a valley savanna in south-west China. We found that savanna lianas had higher vessel density, wood density and lower hydraulically weighted vessel diameter and theoretical hydraulic conductivity than tropical seasonal rainforest lianas.

Differentiation in stem and leaf traits among sympatric lianas, scandent shrubs and trees in a subalpine cold temperate forest.

The scandent shrub plant form is a variant of liana that has upright and self-supporting stems when young but later becomes a climber. We aimed to explore the associations of stem and leaf traits among sympatric lianas, scandent shrubs and trees, and the effects of growth form and leaf habit on variation in stem or leaf traits. We measured 16 functional traits related to stem xylem anatomy, leaf morphology and nutrient stoichiometry in eight liana, eight scandent shrub and 21 tree species co-occurring in a subalpine cold temperate forest at an elevation of 2600-3200 m in Southwest China.

Maternal responses to dead infants in Yunnan snub-nosed monkey (Rhinopithecus bieti) in the Baimaxueshan Nature Reserve, Yunnan, China.

How a nonhuman primate mother responds to her dead infant is an indication of maternal behavior and perspectives on death. Here we describe three cases of a mother's response toward her dead infant in Yunnan snub-nosed monkeys (Rhinopithecus bieti) at Baimaxueshan Nature Reserve in Yunnan, China. The mother, whose infant died at 1 month of age, showed strong maternal affection to the corpse and carried it for 4 days.