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121.
In an era of rapid global change, our ability to understand and predict Earth's natural systems is lagging behind our ability to monitor and measure changes in the biosphere. Bottlenecks to informing models with observations have reduced our capacity to fully exploit the growing volume and variety of available data. Here, we take a critical look at the information infrastructure that connects ecosystem modeling and measurement efforts, and propose a roadmap to community cyberinfrastructure development that can reduce the divisions between empirical research and modeling and accelerate the pace of discovery. A new era of data‐model integration requires investment in accessible, scalable, and transparent tools that integrate the expertise of the whole community, including both modelers and empiricists. This roadmap focuses on five key opportunities for community tools: the underlying foundations of community cyberinfrastructure; data ingest; calibration of models to data; model‐data benchmarking; and data assimilation and ecological forecasting. This community‐driven approach is a key to meeting the pressing needs of science and society in the 21st century.  相似文献   
122.

Deforestation, plantation expansion and other human activities in tropical ecosystems are often associated with biological invasions. These processes have been studied for above-ground organisms, but associated changes below the ground have received little attention. We surveyed rainforest and plantation systems in Jambi province, Sumatra, Indonesia, to investigate effects of land-use change on the diversity and abundance of earthworms—a major group of soil-ecosystem engineers that often is associated with human activities. Density and biomass of earthworms increased 4—30-fold in oil palm and rubber monoculture plantations compared to rainforest. Despite much higher abundance, earthworm communities in plantations were less diverse and dominated by the peregrine morphospecies Pontoscolex corethrurus, often recorded as invasive. Considering the high deforestation rate in Indonesia, invasive earthworms are expected to dominate soil communities across the region in the near future, in lieu of native soil biodiversity. Ecologically-friendly management approaches, increasing structural habitat complexity and plant diversity, may foster beneficial effects of invasive earthworms on plant growth while mitigating negative effects on below-ground biodiversity and the functioning of the native soil animal community.

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In many aquatic animals, predator avoidance can be stimulated by chemical cues, including those released by injured prey (alarm cues). Alarm cues of both conspecific and heterospecific origin have been identified within several fish taxa, where phylogenetic conservation of the cue-response complex is common. Turbellarian flatworms (planaria) are among the simplest animals known to respond to chemical cues released by injured conspecifics. We examined how two locally sympatric planaria species respond to conspecific and heterospecific chemical cues using macerated tissue suspensions. Brown (Girardia tigrina) and black (Dugesia dorotocephala) planaria both exhibited avoidance behavior when presented conspecific cues. Despite a significant twofold difference in body size (black > brown), stimulus prepared from a single (1×) individual of either species elicited avoidance. Increasing brown planaria cue concentration by macerating two individuals (2×) produced a significant increase in conspecific avoidance. Heterospecific stimuli produced asymmetric results. Black planaria avoided the brown planaria stimulus, but only in the higher concentration (2×) trials. Brown planaria did not consistently exhibit avoidance of the black planaria stimulus and some brown subjects approached and consumed black planarian tissues. Our results expand the demonstrated occurrence of alarm cues among planaria and suggest that avoidance behavior can be mediated by multiple environmental and intrinsic factors in freshwater Turbellaria.  相似文献   
125.
Vesicle trafficking plays an important role in cell division, establishment of cell polarity, and translation of environmental cues to developmental responses. However, the molecular mechanisms regulating vesicle trafficking remain poorly understood. Here, we report that the evolutionarily conserved caspase-related protease separase (EXTRA SPINDLE POLES [ESP]) is required for the establishment of cell polarity and cytokinesis in Arabidopsis thaliana. At the cellular level, separase colocalizes with microtubules and RabA2a (for RAS GENES FROM RAT BRAINA2a) GTPase-positive structures. Separase facilitates polar targeting of the auxin efflux carrier PIN-FORMED2 (PIN2) to the rootward side of the root cortex cells. Plants with the radially swollen4 (rsw4) allele with compromised separase activity, in addition to mitotic failure, display isotropic cell growth, perturbation of auxin gradient formation, slower gravitropic response in roots, and cytokinetic failure. Measurements of the dynamics of vesicle markers on the cell plate revealed an overall reduction of the delivery rates of KNOLLE and RabA2a GTPase in separase-deficient roots. Furthermore, dissociation of the clathrin light chain, a protein that plays major role in the formation of coated vesicles, was slower in rsw4 than in the control. Our results demonstrate that separase is a key regulator of vesicle trafficking, which is indispensable for cytokinesis and the establishment of cell polarity.  相似文献   
126.
Constrained to develop within the seed, the plant embryo must adapt its shape and size to fit the space available. Here, we demonstrate how this adjustment shapes metabolism of photosynthetic embryo. Noninvasive NMR-based imaging of the developing oilseed rape (Brassica napus) seed illustrates that, following embryo bending, gradients in lipid concentration became established. These were correlated with the local photosynthetic electron transport rate and the accumulation of storage products. Experimentally induced changes in embryo morphology and/or light supply altered these gradients and were accompanied by alterations in both proteome and metabolome. Tissue-specific metabolic models predicted that the outer cotyledon and hypocotyl/radicle generate the bulk of plastidic reductant/ATP via photosynthesis, while the inner cotyledon, being enclosed by the outer cotyledon, is forced to grow essentially heterotrophically. Under field-relevant high-light conditions, major contribution of the ribulose-1,5-bisphosphate carboxylase/oxygenase–bypass to seed storage metabolism is predicted for the outer cotyledon and the hypocotyl/radicle only. Differences between in vitro– versus in planta–grown embryos suggest that metabolic heterogeneity of embryo is not observable by in vitro approaches. We conclude that in vivo metabolic fluxes are locally regulated and connected to seed architecture, driving the embryo toward an efficient use of available light and space.  相似文献   
127.
Felids in captivity are often inactive and elusive in zoos, leading to a frustrating visitor experience. Eight roars were recorded from an adult male lion and played back over speakers as auditory enrichment to benefit the lions while simultaneously enhancing the zoo visitor experience. In addition, ungulates in an adjacent exhibit were observed to ensure that the novel location and increased frequency of roars did not lead to a stress or fear response. The male lion in this study roared more in the playback phase than in the baseline phases while not increasing any behaviors that would indicate compromised welfare. In addition, zoo visitors remained at the lion exhibit longer during playback. The nearby ungulates never exhibited any reactions stronger than orienting to playbacks, identical to their reactions to live roars. Therefore, naturalistic playbacks of lion roars are a potential form of auditory enrichment that leads to more instances of live lion roars and enhances the visitor experience without increasing the stress levels of nearby ungulates or the lion themselves, who might interpret the roar as that of an intruder.  相似文献   
128.
As nonhuman animals age, geriatric individuals require additional care and veterinary support to ensure their well being. The focus on lifelong care is a relatively newer approach when providing good welfare, and few studies have examined how veterinary care impacts behavior at different ages or how best to accommodate geriatric individuals in zoos. The objectives of this study were to (a) assess both the immediate and long-term (one year later) behavioral impacts of cataract removal for macaroni (Eudyptes chrysolophus) and southern rockhopper (Eudyptes chrysocome) penguins; (b) compare the behavior of penguins following cataract surgery to that of other conspecifics in the same habitat; and (c) monitor the impacts of cataract surgery on swimming behavior using time-depth recorders. Individual responses to cataract removal differed in direction and magnitude, and these mixed results highlight that welfare is experienced and thus measured at the individual level. Positive responses included increased habitat use, increased time spent swimming, and increased rates of affiliative interactions. This study highlights the importance of assessing welfare impacts of veterinary interventions on geriatric individuals.  相似文献   
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130.

Introduction

The aim of this study was to determine the factors, including markers of bone resorption and bone formation, which determine catabolic and anabolic periarticular bone changes in patients with rheumatoid arthritis (RA).

Methods

Forty RA patients received high-resolution peripheral quantitative computed tomography (HR-pQCT) analysis of the metacarpophalangeal joints II and III of the dominantly affected hand at two sequential time points (baseline, one year follow-up). Erosion counts and scores as well as osteophyte counts and scores were recorded. Simultaneously, serum markers of bone resorption (C-terminal telopeptide of type I collagen (CTX I), tartrate-resistant acid phosphatase 5b (TRAP5b)), bone formation (bone alkaline phosphatase (BAP), osteocalcin (OC)) and calcium homeostasis (parathyroid hormone (PTH), 25-hydroxyvitamin D3 (Vit D)) were assessed. Bone biomarkers were correlated to imaging data by partial correlation adjusting for various demographic and disease-specific parameters. Additionally, imaging data were analyzed by mixed linear model regression.

Results

Partial correlation analysis showed that TRAP5b levels correlate significantly with bone erosions, whereas BAP levels correlate with osteophytes at both time points. In the mixed linear model with erosions as the dependent variable, disease duration (P <0.001) was the key determinant for these catabolic bone changes. In contrast, BAP (P = 0.001) as well as age (P = 0.018), but not disease duration (P = 0.762), were the main determinants for the anabolic changes (osteophytes) of the periarticular bone in patients with RA.

Conclusions

This study shows that structural bone changes assessed with HR-pQCT are accompanied by alterations in systemic markers of bone resorption and bone formation. Besides, it can be shown that bone erosions in RA patients depend on disease duration, whereas osteophytes are associated with age as well as serum level of BAP. Therefore, these data not only suggest that different variables are involved in formation of bone erosions and osteophytes in RA patients, but also that periarticular bone changes correlate with alterations in systemic markers of bone metabolism, pointing out BAP as an important parameter.  相似文献   
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