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Shrub cover in semiarid rangelands may induce changes in soil resources and ecosystem functioning. However, it is unknown the real influence that shrub vegetation has on soil quality in rangelands used for livestock purposes. We evaluated the shrub cover effect on 12 chemical and biochemical parameters of soil quality. In a semiarid Monte rangeland of Argentina, 6 paddocks were selected and 10 m transects were placed in a patch with (Sh) and without shrubs (WSh). Then, sites with grasses (Sh‐G and WSh‐G), bare ground‐litter (Sh‐BL and WSh‐BL), and under shrub cover (Sh‐S) were selected. In spring 2017 and 2018, a composite soil sample (0–10 cm in depth) was taken at each site (n = 6). Sh‐G and Sh‐S sites presented high values of soil organic matter, soil organic nitrogen, particulate organic matter (POM), and cellulase activity (CA); WSh‐BL and Sh‐BL sites were associated with the lowest contents of these variables. For the rest of the soil quality parameters, the soil sampling sites showed similar values. These results show that woody presence should not be directly linked to soil quality loss. Although we did not detect a shrub effect in all parameters studied, in the context of appropriate grazing management, the presence of plant species of different functional groups has a positive effect on organic matter and N content of soil close to them. Moreover, in these sites, high POM values represent an important reservoir of potentially available nutrients, and promote CA necessary for fresh litter decomposition improving the soil quality of semiarid rangelands. [ABSTRACT FROM AUTHOR]

Despite the predominant role of bud banks in population regeneration and community dynamics, they have received far less attention than deserved. In particular, it remains unexplored how bud bank size and composition respond to different grazing intensities in grasslands. We investigated the size and composition of bud banks under different grazing intensities and regimes on a typical steppe in Inner Mongolia, China. Our results showed that (i) the total bud density in the traditional grazing regime (grazing and haymaking within the same year in the same paddock; 2,444 ± 141 buds m−2) was 30 ± 11% higher (mean ± standard error; p < 0·05) than that in the mixed grazing regime (grazing and haymaking alternate annually in the same paddock; 1,872 ± 109 buds m−2), but they did not change with increasing grazing intensity, (ii) rhizome buds and bulb buds decreased sharply ( p < 0·05) because of grazing in the mixed grazing regime, (iii) bud banks of rhizomatous grasses showed species-specific responses to the increasing grazing intensity: decreasing in Leymus chinensis (Trin.) Tzvel., increasing in Agropyron cristatum (L.) Gaertn. and unresponsive in Carex duriuscula C. A. Mey. Data indicated that (i) the studied grazing intensities had no significant effects on the total bud bank, suggesting that belowground bud bank seems to be tolerant of grazing and (ii) the responses of bud bank to grazing differed with the bud bank type and species, indicating that bud banks could be used for explaining and predicting the dynamics of a natural grassland plant community. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Changes in forest openings affect light quality and quantity, and the magnitude of rainfall that reaches the soil surface. Osmorhiza depauperata, a geophyte, acclimates to changes imposed because of forest openings. We studied which changes in biomass allocation allow acclimation of O. depauperata to the various environments that this species inhabits, and where it develops better. Three light intensities (I4 = 4 %, I26 = 26 %, I64 = 64 % of ambient sunlight) and two moisture levels (M40 = 40-60 %, M80 = 80-100 % field capacity) were evaluated on O. depauperata under greenhouse conditions. Plant biomasses per pot were 0.81, 0.56 and 0.48 g at I26, I4 and I64 light intensities, respectively, after one growing season. The biomass allocation to aboveground tissues and leaf area decreased as light intensity increased. Soil moisture modified only belowground biomass and weight of fine roots. The interaction between soil moisture content and light intensity was consistent. This was because of a significant reduction in total plant biomass under high both soil moisture content and high light intensity. Osmorhiza depauperata growth was favored most at medium light intensities. Changes in biomass allocation among various organs allow this species to inhabit forest habitats with different light intensities. [ABSTRACT FROM AUTHOR]

Natural head motion is important to realistic facial animation and engaging human–computer interactions. In this paper, we present a novel data-driven approach to synthesize appropriate head motion by sampling from trained hidden markov models (HMMs). First, while an actress recited a corpus specifically designed to elicit various emotions, her 3D head motion was captured and further processed to construct a head motion database that included synchronized speech information. Then, an HMM for each discrete head motion representation (derived directly from data using vector quantization) was created by using acoustic prosodic features derived from speech. Finally, first-order Markov models and interpolation techniques were used to smooth the synthesized sequence. Our comparison experiments and novel synthesis results show that synthesized head motions follow the temporal dynamic behavior of real human subjects. Copyright © 2005 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Background Aims Discussion Post‐traumatic stress disorder (PTSD) poses a global public health challenge. Evidence‐based psychotherapies (EBPs) for PTSD reduce symptoms and improve functioning (Forbes et al., Guilford Press, 2020, 3). However, a number of barriers to access and engagement with these interventions prevail. As a result, the use of EBPs in community settings remains disappointingly low (Charney et al., Psychological Trauma: Theory, Research, Practice, and Policy, 11, 2019, 793; Richards et al., Community Mental Health Journal, 53, 2017, 215), and not all patients who receive an EBP for PTSD benefit optimally (Asmundson et al., Cognitive Behaviour Therapy, 48, 2019, 1). Advancements in artificial intelligence (AI) have introduced new possibilities for increasinfg access to and quality of mental health interventions.The present paper reviews key barriers to accessing and engaging in EBPs for PTSD, discusses current applications of AI in PTSD treatment and provides recommendations for future AI integrations aimed at reducing barriers to access and engagement.We propose that AI may be utilized to (1) assess treatment fidelity; (2) elucidate novel predictors of treatment dropout and outcomes; and (3) facilitate patient engagement with the tasks of therapy, including therapy practice. Potential avenues for technological advancements are also considered. [ABSTRACT FROM AUTHOR]