Global mapping of soil salinity change Ivushkin, Konstantin; Bartholomeus, Harm; Bregt, Arnold K. ...
Remote sensing of environment,
09/2019, Letnik:
231
Journal Article
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Soil salinity increase is a serious and global threat to agricultural production. The only database that currently provides soil salinity data with global coverage is the Harmonized World Soil ...Database, but it has several limitations when it comes to soil salinity assessment. Therefore, a new assessment is required. We hypothesized that combining soil properties maps with thermal infrared imagery and a large set of field observations within a machine learning framework will yield a global soil salinity map. The thermal infrared imagery acts as a dynamic variable and allows us to characterize the soil salinity change. For this purpose we used Google Earth Engine computational environment. The random forest classifier was trained using 7 soil properties maps, thermal infrared imagery and the ECe point data from the WoSIS database. In total, six maps were produced for 1986, 2000, 2002, 2005, 2009, 2016. The validation accuracy of the resulting maps was in the range of 67–70%. The total area of salt affected lands by our assessment is around 1 billion hectares, with a clear increasing trend. Comparison with 3 studies investigating local trends of soil salinity change showed that our assessment was in correspondence with 2 of these studies. The global map of soil salinity change between 1986 and 2016 was produced to characterize the spatial distribution of the change. We conclude that combining soil properties maps and thermal infrared imagery allows mapping of soil salinity development in space and time on a global scale.
•Soil properties maps combined with thermal imagery can be used to map soil salinity.•Thermal imagery can act as a dynamic variable.•Soil salinisation is increasing on global scale.
The tricarboxylic acid (TCA) cycle, otherwise known as the Krebs cycle, is a central metabolic pathway that performs the essential function of oxidizing nutrients to support cellular bioenergetics. ...More recently, it has become evident that TCA cycle behavior is dynamic, and products of the TCA cycle can be co-opted in cancer and other pathologic states. In this review, we revisit the TCA cycle, including its potential origins and the history of its discovery. We provide a detailed accounting of the requirements for sustained TCA cycle function and the critical regulatory nodes that can stimulate or constrain TCA cycle activity. We also discuss recent advances in our understanding of the flexibility of TCA cycle wiring and the increasingly appreciated heterogeneity in TCA cycle activity exhibited by mammalian cells. Deeper insight into how the TCA cycle can be differentially regulated and, consequently, configured in different contexts will shed light on how this pathway is primed to meet the requirements of distinct mammalian cell states.
A new conceptualization and measurement of social dominance orientation-individual differences in the preference for group based hierarchy and inequality-is introduced. In contrast to previous ...measures of social dominance orientation that were designed to be unidimensional, the new measure (SDO7) embeds theoretically grounded subdimensions of SDO-SDO-Dominance (SDO-D) and SDO-Egalitarianism (SDO-E). SDO-D constitutes a preference for systems of group-based dominance in which high status groups forcefully oppress lower status groups. SDO-E constitutes a preference for systems of group-based inequality that are maintained by an interrelated network of subtle hierarchy-enhancing ideologies and social policies. Confirmatory factor and criterion validity analyses confirmed that SDO-D and SDO-E are theoretically distinct and dissociate in terms of the intergroup outcomes they best predict. For the first time, distinct personality and individual difference bases of SDO-D and SDO-E are outlined. We clarify the construct validity of SDO by strictly assessing a preference for dominance hierarchies in general, removing a possible confound relating to support for hierarchy benefitting the ingroup. Consistent with this, results show that among members of a disadvantaged ethnic minority group (African Americans), endorsement of SDO7 is inversely related to ingroup identity. We further demonstrate these effects using nationally representative samples of U.S. Blacks and Whites, documenting the generalizability of these findings. Finally, we introduce and validate a brief 4-item measure of each dimension. This article importantly extends our theoretical understanding of one of the most generative constructs in social psychology, and introduces powerful new tools for its measurement.
A major concern with co-administration of different drugs is the high risk of interference between their mechanisms of action, known as adverse drug-drug interactions (DDIs), which can cause serious ...injuries to the organism. Although several computational methods have been proposed for identifying potential adverse DDIs, there is still room for improvement. Existing methods are not explicitly based on the knowledge that DDIs are fundamentally caused by chemical substructure interactions instead of whole drugs' chemical structures. Furthermore, most of existing methods rely on manually engineered molecular representation, which is limited by the domain expert's knowledge.We propose substructure-substructure interaction-drug-drug interaction (SSI-DDI), a deep learning framework, which operates directly on the raw molecular graph representations of drugs for richer feature extraction; and, most importantly, breaks the DDI prediction task between two drugs down to identifying pairwise interactions between their respective substructures. SSI-DDI is evaluated on real-world data and improves DDI prediction performance compared to state-of-the-art methods. Source code is freely available at https://github.com/kanz76/SSI-DDI.
The phyllosphere—the aerial surfaces of plants, including leaves—is a ubiquitous global habitat that harbors diverse bacterial communities. Phyllosphere bacterial communities have the potential to ...influence plant biogeography and ecosystem function through their influence on the fitness and function of their hosts, but the host attributes that drive community assembly in the phyllosphere are poorly understood. In this study we used high-throughput sequencing to quantify bacterial community structure on the leaves of 57 tree species in a neotropical forest in Panama. We tested for relationships between bacterial communities on tree leaves and the functional traits, taxonomy, and phylogeny of their plant hosts. Bacterial communities on tropical tree leaves were diverse; leaves from individual trees were host to more than 400 bacterial taxa. Bacterial communities in the phyllosphere were dominated by a core microbiome of taxa including Actinobacteria, Alpha-, Beta-, and Gammaproteobacteria, and Sphingobacteria. Host attributes including plant taxonomic identity, phylogeny, growth and mortality rates, wood density, leaf mass per area, and leaf nitrogen and phosphorous concentrations were correlated with bacterial community structure on leaves. The relative abundances of several bacterial taxa were correlated with suites of host plant traits related to major axes of plant trait variation, including the leaf economics spectrum and the wood density–growth/mortality tradeoff. These correlations between phyllosphere bacterial diversity and host growth, mortality, and function suggest that incorporating information on plant–microbe associations will improve our ability to understand plant functional biogeography and the drivers of variation in plant and ecosystem function.
Significance In this study we sequenced bacterial communities present on tree leaves in a neotropical forest in Panama, to quantify the poorly understood relationships between bacterial biodiversity on leaves (the phyllosphere) vs. host tree attributes. Bacterial community structure on leaves was highly correlated with host evolutionary relatedness and suites of plant functional traits related to host ecological strategies for resource uptake and growth/mortality tradeoffs. The abundance of several bacterial taxa was correlated with host growth, mortality, and function. Our study quantifies the drivers of variation in plant-associated microbial biodiversity; our results suggest that incorporating information on plant-associated microbes will improve our understanding of the functional biogeography of plants and plant–microbe interactions.
Debate surrounding the issue of inequality and hierarchy between social groups has become increasingly prominent in recent years. At the same time, individuals disagree about the extent to which ...inequality between advantaged and disadvantaged groups exists. Whereas prior work has examined the ways in which individuals legitimize (or delegitimize) inequality as a function of their motivations, we consider whether individuals' orientation toward group-based hierarchy motivates the extent to which they perceive inequality between social groups in the first place. Across 8 studies in both real-world (race, gender, and class) and artificial contexts, and involving members of both advantaged and disadvantaged groups, we show that the more individuals endorse hierarchy between groups, the less they perceive inequality between groups at the top and groups at the bottom. Perceiving less inequality is associated with rejecting egalitarian social policies aimed at reducing it. We show that these differences in hierarchy perception as a function of individuals' motivational orientation hold even when inequality is depicted abstractly using images, and even when individuals are financially incentivized to accurately report their true perceptions. Using a novel methodology to assess accurate memory of hierarchy, we find that differences may be driven by both antiegalitarians underestimating inequality, and egalitarians overestimating it. In sum, our results identify a novel perceptual bias rooted in individuals' chronic motivations toward hierarchy-maintenance, with the potential to influence their policy attitudes.
► We developed
K
Simulation to assess the accuracy of simulated changes explicitly. ► This method truly tests a models’ capacity to explain land-use changes over time. ►
K
Simulation can be applied ...for any model that simulates categorical changes.
Land-use change models are typically calibrated to reproduce known historic changes. Calibration results can then be assessed by comparing two datasets: the simulated land-use map and the actual land-use map at the same time. A common method for this is the Kappa statistic, which expresses the agreement between two categorical datasets corrected for the expected agreement. This expected agreement is based on a stochastic model of random allocation given the distribution of class sizes. However, when a model starts from an initial land-use map and makes changes to it, that stochastic model does not pose a meaningful reference level. This paper introduces
K
Simulation, a statistic that is identical in form to the Kappa statistic but instead applies a more appropriate stochastic model of random allocation of class transitions relative to the initial map. The new method is illustrated on a simple example and then the results of the Kappa statistic and
K
Simulation are compared using the results of a land-use model. It is found that only
K
Simulation truly tests models in their capacity to explain land-use changes over time, and unlike Kappa it does not inflate results for simulations where little change takes place over time.
Social Dominance Orientation Ho, Arnold K.; Sidanius, Jim; Pratto, Felicia ...
Personality & social psychology bulletin,
05/2012, Letnik:
38, Številka:
5
Journal Article
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Social dominance orientation (SDO) is one of the most powerful predictors of intergroup attitudes and behavior. Although SDO works well as a unitary construct, some analyses suggest it might consist ...of two complementary dimensions—SDO-Dominance (SDO-D), or the preference for some groups to dominate others, and SDO-Egalitarianism (SDO-E), a preference for nonegalitarian intergroup relations. Using seven samples from the United States and Israel, the authors confirm factor-analytic evidence and show predictive validity for both dimensions. In the United States, SDO-D was theorized and found to be more related to old-fashioned racism, zero-sum competition, and aggressive intergroup phenomena than SDO-E; SDO-E better predicted more subtle legitimizing ideologies, conservatism, and opposition to redistributive social policies. In a contentious hierarchical intergroup context (the Israeli–Palestinian context), SDO-D better predicted both conservatism and aggressive intergroup attitudes. Fundamentally, these analyses begin to establish the existence of complementary psychological orientations underlying the preference for group-based dominance and inequality.
The accuracy of state-of-the-art atomic clocks is derived from the insensitivity of narrow optical atomic resonances to environmental perturbations. Two such resonances in singly ionized lutetium ...have been identified with potentially lower sensitivities compared to other clock candidates. Here we report measurement of the most significant unknown atomic property of both transitions, the static differential scalar polarizability. From this, the fractional blackbody radiation shift for one of the transitions is found to be -1.36(9) × 10
at 300 K, the lowest of any established optical atomic clock. In consideration of leading systematic effects common to all ion clocks, both transitions compare favorably to the most accurate ion-based clocks reported to date. This work firmly establishes Lu
as a promising candidate for a future generation of more accurate optical atomic clocks.
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