scholarly journals Classifying Large Wildfires in the United States by Land Cover

2020 ◽  
Vol 12 (18) ◽  
pp. 2966
Author(s):  
Brice B. Hanberry

Fire is an ecological process that also has socio-economic effects. To learn more about fire occurrence, I examined relationships between land classes and about 12,000 spatially delineated large wildfires (defined here as uncontrolled fires ≥200 ha, although definitions vary) during 1999 to 2017 in the conterminous United States. Using random forests, extreme gradient boosting, and c5.0 classifiers, I modeled all fires, first years (1999 to 2002), last years (2014 to 2017), the eastern, central, and western United States and seven ecoregions. The three classifiers performed well (true positive rates 0.82 to 0.94) at modeling all fires and fires by year, region, and ecoregion. The random forests classifier did not predict to other time intervals or regions as well as other classifiers and models were not constant in time and space. For example, the eastern region overpredicted fires in the western region and models for the western region underpredicted fires in the eastern region. Overall, greater abundance of herbaceous grasslands, or herbaceous wetlands in the eastern region, and evergreen forest and low abundance of crops and pasture characterized most large fires, even with regional differences. The 14 states in the northeastern United States with no or few large fires contained limited herbaceous area and abundant crops or developed lands. Herbaceous vegetation was the most important variable for fire occurrences in the western region. Lack of crops was most important for fires in the central region and a lack of pasture, crops, and developed open space was most important for fires in the eastern region. A combination of wildlands vegetation was most influential for most ecoregions, although herbaceous vegetation alone and lack of pasture, crops, and developed open space also were influential. Despite departure from historical fire regimes, these models demonstrated that herbaceous vegetation remains necessary for fires and that evergreen forests in particular are fire-prone, while reduction of vegetation surrounding housing developments will help provide a buffer to reduce large fires.

2021 ◽  
Author(s):  
Younes Shekarian ◽  
Elham Rahimi ◽  
Naser Shekarian ◽  
Mohammad Rezaee ◽  
Pedram Roghanchi

Abstract In the United States, an unexpected and severe increase in coal miners’ lung diseases in the late 1990s prompted researchers to investigate the causes of the disease resurgence. This study aims to scrutinize the effects of various mining parameters, including coal rank, mine size, mining method, coal seam height, and geographical location on the prevalence of CWP in surface and underground coal mines. A comprehensive dataset was created using the U.S. Mine Safety and Health Administration (MSHA) Employment and Accident/Injury databases. The information was merged based on the mine ID by utilizing SQL data management software. A total number of 123,643 mine-year observations were included in the statistical analysis. Generalized Estimating Equation (GEE) model was used to conduct a statistical analysis on a total of 29,707, and 32,643 mine-year observations for underground and surface coal mines, respectively. The results of the econometrics approach revealed that coal workers in underground coal mines are at a greater risk of CWP comparing to those of surface coal operations. Furthermore, underground coal mines in the Appalachia and Interior regions are at a higher risk of CWP prevalence than the Western region. Surface coal mines in the Appalachian coal region are more susceptible to CWP than miners in the Western region. The analysis also indicated that coal workers working in smaller mines are more vulnerable to CWP than those in large mine sizes. Furthermore, coal workers in thin-seam underground mine operations are more likely to develop CWP.


1944 ◽  
Vol 39 (3) ◽  
pp. 337-430 ◽  
Author(s):  
W. A. SAWYER ◽  
K. P. MEYER ◽  
M. D. EATON ◽  
J. H. BAUER ◽  
PERSIS PUTNAM ◽  
...  

1944 ◽  
Vol 40 (1) ◽  
pp. 35-107 ◽  
Author(s):  
W. A. SAWYER ◽  
K. F MEYER ◽  
M. D EATON ◽  
J. H BAUER ◽  
PERSIS PUTNAM ◽  
...  

Author(s):  
Younes Shekarian ◽  
Elham Rahimi ◽  
Naser Shekarian ◽  
Mohammad Rezaee ◽  
Pedram Roghanchi

AbstractIn the United States, an unexpected and severe increase in coal miners’ lung diseases in the late 1990s prompted researchers to investigate the causes of the disease resurgence. This study aims to scrutinize the effects of various mining parameters, including coal rank, mine size, mine operation type, coal seam height, and geographical location on the prevalence of coal worker's pneumoconiosis (CWP) in surface and underground coal mines. A comprehensive dataset was created using the U.S. Mine Safety and Health Administration (MSHA) Employment and Accident/Injury databases. The information was merged based on the mine ID by utilizing SQL data management software. A total number of 123,589 mine-year observations were included in the statistical analysis. Generalized Estimating Equation (GEE) model was used to conduct a statistical analysis on a total of 29,707, and 32,643 mine-year observations for underground and surface coal mines, respectively. The results of the econometrics approach revealed that coal workers in underground coal mines are at a greater risk of CWP comparing to those of surface coal operations. Furthermore, underground coal mines in the Appalachia and Interior regions are at a higher risk of CWP prevalence than the Western region. Surface coal mines in the Appalachian coal region are more likely to CWP development than miners in the Western region. The analysis also indicated that coal workers working in smaller mines are more vulnerable to CWP than those in large mine sizes. Furthermore, coal workers in thin-seam underground mine operations are more likely to develop CWP.


Author(s):  
Epiphanie Nyirabahizi ◽  
Gregory H. Tyson ◽  
Heather Tate ◽  
Michael S. Williams ◽  
Gurinder S. Saini ◽  
...  

As part of the National Antimicrobial Resistance Monitoring System (NARMS) activities, the United States Department of Agriculture (USDA) Food Safety Inspection Service (FSIS) collected cecal samples from food animal slaughter facilities throughout the country between 2014 and 2018. Of the 26,780 cecal samples from cattle, swine, chicken and turkey , 6,350 (23.71%) tested positive for Salmonella . NARMS tested Salmonella for susceptibility to aminoglycosides, folate pathway inhibitors, macrolides, phenicols, quinolones, beta lactams, and tetracyclines. Using the regional subdivisions defined in the USDA Office of Investigation, we used chi-square test to assess potential association between the region from which the samples were collected and both Salmonella prevalence and susceptibility. The results show a significant association between region and Salmonella prevalence, when accounting for source and establishment size, with the southeast region having the highest probability of finding Salmonella . However, the western region had the highest resistance probability across all antimicrobial classes except for macrolides, which showed no regional association. This association between region and resistance was strongest among isolates from cattle. Analysis of whole-genome sequencing data indicated that a significantly higher prevalence of Salmonella Newport in cattle in the western region (accounting for 9.52% of cattle isolates, compared to 3.44% in other regions) may account for the greater resistance to multiple drug classes. Approximately 90% of Salmonella Newport in the west exhibited the MDR-AmpC phenotype encoded by aph(3'')-Ib/aph(6)-Id , bla CMY-2 , floR , sul2 , and tetA. . Thus, differences in resistance across regions may be due to geographical differences in the prevalence of specific Salmonella serotypes and their accompanying resistance genes.


2021 ◽  
Author(s):  
Ibrahim Abaker Targio Hashem ◽  
Raja Sher Afgun Usmani ◽  
Asad Ali Shah ◽  
Abdulwahab Ali Almazroi ◽  
Muhammad Bilal

The COVID-19 pandemic has emerged as the world's most serious health crisis, affecting millions of people all over the world. The majority of nations have imposed nationwide curfews and reduced economic activity to combat the spread of this infectious disease. Governments are monitoring the situation and making critical decisions based on the daily number of new cases and deaths reported. Therefore, this study aims to predict the daily new deaths using four tree-based ensemble models i.e., Gradient Tree Boosting (GB), Random Forest (RF), Extreme Gradient Boosting (XGBoost), and Voting Regressor (VR) for the three most affected countries, which are the United States, Brazil, and India. The results showed that VR outperformed other models in predicting daily new deaths for all three countries. The predictions of daily new deaths made using VR for Brazil and India are very close to the actual new deaths, whereas the prediction of daily new deaths for the United States still needs to be improved.<br>


1970 ◽  
Vol 16 ◽  
pp. 207-240
Author(s):  
Павел Роберт Маґочій

AbstractThe Fellow Who Made Himself President of a European Republic. Gregory Ignatius Zhatkovych The study is the first comprehensive biography of Gregory Ignatius Zhatkovych, a Pittsburgh-based lawyer, who in 1918-1919 was instrumental in the creation of Czechoslovakia and the inclusion of its far eastern region, Subcarpathian Rus’/ Ruthenia, into the new country. Until now, information about Gregory Zhatkovych has come primarily from the extensive body of historical literature describing how Subcarpathian Rus’ was incorporated into Czechoslovakia at the close of World War I. The facts related in this literature are more or less the same. Their assessment, however, differs rather substantially depending on the ideological orientation of the authors and / or the time when they were writing. In the above literature Gregory Zhatkovych figures prominently, although until most recently he has been described in very different terms. For some authors, he is hailed as a friend of the young democratic Czechoslovak state. For others, especially those of Marxist persuasion, he is denigrated as a representative of Rusyn-American “bourgeois nationalist organizations”, a “lackey” and “loyal son of American capitalism”, and “an agent of American imperialism”. Finally, there are those who consider Zhatkovych a Carpatho-Rusyn patriot who did his best – but ultimately failed – to as sure that the promises made by the Czechoslovak government for Subcarpathian self-rule would be fulfilled. Despite his historic importance, to date there is no biography of Gregory Zhatkovych other than a few brief encyclopedic entries. Aside from their brevity, these entries generally focus on the few years just after World War I, when he was politically active in Europe. But Zhatkovych had a life both before and after those years as a lawyer and political activist in the United States, in particular in western Pennsylvania. Based on recently uncovered correspondence between Zhatkovych and his wife and between the wife and her sister, as well as unpublished biographical data provided by his surviving family members, the recently published correspondence with President Masaryk, and several rare newspaper reports especially from western Pennsylvania, this is the first study to provide a comprehensive biography that spans Gregory Zhatkovych’s pre- and especially post-World War I career in the United States until his death in 1967.


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