global patterns
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2022 ◽  
Author(s):  
Damien Delforge ◽  
Olivier de Viron ◽  
Fabien Durand ◽  
Veronique Dehant
Keyword(s):  

Computers ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 8
Author(s):  
Benjamín Luna-Benoso ◽  
José Cruz Martínez-Perales ◽  
Jorge Cortés-Galicia ◽  
Rolando Flores-Carapia ◽  
Víctor Manuel Silva-García

Any cancer type is one of the leading death causes around the world. Skin cancer is a condition where malignant cells are formed in the tissues of the skin, such as melanoma, known as the most aggressive and deadly skin cancer type. The mortality rates of melanoma are associated with its high potential for metastasis in later stages, spreading to other body sites such as the lungs, bones, or the brain. Thus, early detection and diagnosis are closely related to survival rates. Computer Aided Design (CAD) systems carry out a pre-diagnosis of a skin lesion based on clinical criteria or global patterns associated with its structure. A CAD system is essentially composed by three modules: (i) lesion segmentation, (ii) feature extraction, and (iii) classification. In this work, a methodology is proposed for a CAD system development that detects global patterns using texture descriptors based on statistical measurements that allow melanoma detection from dermoscopic images. Image analysis was carried out using spatial domain methods, statistical measurements were used for feature extraction, and a classifier based on cellular automata (ACA) was used for classification. The proposed model was applied to dermoscopic images obtained from the PH2 database, and it was compared with other models using accuracy, sensitivity, and specificity as metrics. With the proposed model, values of 0.978, 0.944, and 0.987 of accuracy, sensitivity and specificity, respectively, were obtained. The results of the evaluated metrics show that the proposed method is more effective than other state-of-the-art methods for melanoma detection in dermoscopic images.


2021 ◽  
Vol 13 (12) ◽  
pp. 5831-5846
Author(s):  
Xianjin He ◽  
Laurent Augusto ◽  
Daniel S. Goll ◽  
Bruno Ringeval ◽  
Yingping Wang ◽  
...  

Abstract. Soil represents the largest phosphorus (P) stock in terrestrial ecosystems. Determining the amount of soil P is a critical first step in identifying sites where ecosystem functioning is potentially limited by soil P availability. However, global patterns and predictors of soil total P concentration remain poorly understood. To address this knowledge gap, we constructed a database of total P concentration of 5275 globally distributed (semi-)natural soils from 761 published studies. We quantified the relative importance of 13 soil-forming variables in predicting soil total P concentration and then made further predictions at the global scale using a random forest approach. Soil total P concentration varied significantly among parent material types, soil orders, biomes, and continents and ranged widely from 1.4 to 9630.0 (median 430.0 and mean 570.0) mg kg−1 across the globe. About two-thirds (65 %) of the global variation was accounted for by the 13 variables that we selected, among which soil organic carbon concentration, parent material, mean annual temperature, and soil sand content were the most important ones. While predicted soil total P concentrations increased significantly with latitude, they varied largely among regions with similar latitudes due to regional differences in parent material, topography, and/or climate conditions. Soil P stocks (excluding Antarctica) were estimated to be 26.8 ± 3.1 (mean ± standard deviation) Pg and 62.2 ± 8.9 Pg (1 Pg = 1 × 1015 g) in the topsoil (0–30 cm) and subsoil (30–100 cm), respectively. Our global map of soil total P concentration as well as the underlying drivers of soil total P concentration can be used to constraint Earth system models that represent the P cycle and to inform quantification of global soil P availability. Raw datasets and global maps generated in this study are available at https://doi.org/10.6084/m9.figshare.14583375 (He et al., 2021).


Author(s):  
Margaret E Peters ◽  
Michael K Miller

Abstract How does migration affect global patterns of political violence and protest? While political scientists have examined the links between trade and conflict, less attention has been paid to the links between migration and conflict. In this paper, we show that greater emigration reduces domestic political violence by providing exit opportunities for aggrieved citizens and economic benefits to those who remain. Emigration also reduces non-violent forms of political contestation, including protests and strikes, implying that high emigration rates can produce relatively quiescent populations. However, larger flows of emigrants to democracies can increase non-violent protest in autocracies, as exposure to freer countries spreads democratic norms and the tools of peaceful opposition. We use instrumental variables analysis to account for the endogeneity of migration flows and find robust results for a range of indicators of civil violence and protest from 1960 to 2010.


2021 ◽  
Author(s):  
Huijie Qiao ◽  
Michael Orr ◽  
Qinmin Yang ◽  
Xiangjiang Zhan ◽  
Fumin Lei ◽  
...  

Birdwatching is a global phenomenon involving many thousands of people. Citizen science generates data providing insights into global patterns of bird distribution across space and time, yet how the pandemic may cast a longer shadow remains unassessed. Here, we explore whether pandemic restrictions influenced observations globally from 2020-May 2021, considering also GDPc and tourism income. We analysed 10,338 bird species (93% of all bird species) and found that whilst high-income regions recover to pre-pandemic assessment rates quickly, middle and low-income regions remain at low levels. Furthermore, protected areas see huge losses in recorded richness. Whilst observer count increased overall, the number of bird species recorded dramatically decreased, especially in 2020. These trends are most marked in developing countries and regions, especially where tourism is important. Due to increased bushmeat consumption during the pandemic, some species may become more threatened, but with no data we cannot yet discern such trends.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xuejun Yang ◽  
Carol C. Baskin ◽  
Jerry M. Baskin ◽  
Robin J. Pakeman ◽  
Zhenying Huang ◽  
...  

AbstractSoil seed banks represent a critical but hidden stock for potential future plant diversity on Earth. Here we compiled and analyzed a global dataset consisting of 15,698 records of species diversity and density for soil seed banks in natural plant communities worldwide to quantify their environmental determinants and global patterns. Random forest models showed that absolute latitude was an important predictor for diversity of soil seed banks. Further, climate and soil were the major determinants of seed bank diversity, while net primary productivity and soil characteristics were the main predictors of seed bank density. Moreover, global mapping revealed clear spatial patterns for soil seed banks worldwide; for instance, low densities may render currently species-rich low latitude biomes (such as tropical rain-forests) less resilient to major disturbances. Our assessment provides quantitative evidence of how environmental conditions shape the distribution of soil seed banks, which enables a more accurate prediction of the resilience and vulnerabilities of plant communities and biomes under global changes.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Zhichao Zhang ◽  
Shuai Yu ◽  
Jing Li ◽  
Yanbin Zhu ◽  
Siqi Jiang ◽  
...  

Abstract Background Genomic imprinting is an epigenetic phenomenon mainly occurs in endosperm of flowering plants. Genome-wide identification of imprinted genes have been completed in several dicot Cruciferous plant and monocot crops. Results Here, we analyzed global patterns of allelic gene expression in developing endosperm of sunflower which belongs to the composite family. Totally, 691 imprinted loci candidates were identified in 12 day-after-pollination sunflower endosperm including 79 maternally expressed genes (MEG) and 596 paternally expressed genes (PEG), 6 maternally expressed noncoding RNAs (MNC) and 10 paternally expressed noncoding RNAs (PNC). And a clear clustering of imprinted genes throughout the rapeseed genome was identified. Generally, imprinting in sunflower is conserved within a species, but intraspecific variation also was detected. Limited loci in sunflower are imprinted in other several different species. The DNA methylation pattern around imprinted genes were investigated in embryo and endosperm tissues. In CG context, the imprinted genes were significantly associated with differential methylated regions exhibiting hypomethylation in endosperm and hypermethylation in embryo, which indicated that the maternal demethylation in CG context potentially induce the genomic imprinting in endosperm. Conclusion Our study would be helpful for understanding of genomic imprinting in plants and provide potential basis for further research in imprinting in sunflower.


Author(s):  
Nicholas Freudenberg

Since the mid-20 century, corporations have gained increasing political and economic power to shape the living conditions, lifestyles, governance processes, and environmental exposures that determine global patterns of health and disease. Globalization, the growth of the financial sector, deregulation, and increasing corporate control of science and technology have provided corporations with new power to influence the mechanisms that determine human and planetary health. A growing body of public health and social science scholarship analyzes how corporate use of this economic and political power has become a fundamental determinant of the most serious health crises facing the world. In response, governments, civil society groups and social movements have developed new strategies to challenge corporate power to shape global health governance, protect public health, and reduce health inequities.


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