scholarly journals Fresh-water sponges in the collection of the United States National Museum.—Part II. Specimens from North and South America

1909 ◽  
Vol 37 (1712) ◽  
pp. 401-406 ◽  
Author(s):  
Nelson Annandale
Keyword(s):  
United States ◽  
South America ◽  
Fresh Water ◽  
The United States ◽  
National Museum ◽  
United States National Museum ◽  
North And South America ◽  
North And South

Th e chironomidae (Diptera) of Australia.

1961 ◽  
Vol 9 (4) ◽  
pp. 611 ◽  
Author(s):  
P Freeman
Keyword(s):  
United States ◽  
South America ◽  
British Museum ◽  
The United States ◽  
National Museum ◽  
Type Specimens ◽  
Systematic Account ◽  
United States National Museum

This is a systematic account of the species of Chironomidae from Australia based mainly on collections in Australian museums, the British Museum, and the United States National Museum. One hundred and twenty-nine species are described, 69 of them new, and keys are given to subfamilies, genera, and species. The classification proposed by Brundin (1956) has been adopted; in this, the subfamilies Diamesinae, Clunioninae, and Corynoneurinae are treated as, at the most, tribes of the subfamily Orthocladiinae. Type specimens of species described by Macquart, Walker, and Skuse have been examined and the species redescribed and figured; an attempt has been made to identify Kieffer's species, the types of which are probably lost. Some account is given of the composition of the fauna, and the presence of an element in the more primitive genera similar to the fauna of the southern part of South America has been noted.

Jujuyaspis borealis and associated trilobites and conodonts from the Lower Ordovician of Texas and Utah

1987 ◽  
Vol 61 (1) ◽  
pp. 112-121 ◽  
Author(s):  
James H. Stitt ◽  
James F. Miller
Keyword(s):  
United States ◽  
South America ◽  
North American ◽  
The United States ◽  
International Agreement ◽  
Lower Ordovician ◽  
Central Texas ◽  
North And South America ◽  
First Time ◽  
North And South

Jujuyaspis borealis is reported from earliest Ordovician (North American usage) limestones in central Texas and western Utah, the first time this species has been recognized in the United States. Jujuyaspis is a widespread olenid trilobite that occurs near the base of the Tremadoc Series in a variety of lithologies in North and South America, Europe, and Asia. When international agreement is reached on the exact horizon at or near the base of the Tremadoc Series that is to be used as the Cambrian–Ordovician boundary, Jujuyaspis will likely prove to be a very useful taxon for recognition of the boundary interval.

scholarly journals The concern of Andrey Sheptytsky, the Metropolitan bishop, about Ukrainian Emigrants in North and South America

1970 ◽  
Vol 23 ◽  
pp. 258-270
Author(s):  
Adam Kubasik
Keyword(s):  
United States ◽  
Twentieth Century ◽  
North America ◽  
South America ◽  
The United States ◽  
Immigrant Communities ◽  
Political Agitation ◽  
The Usa ◽  
North And South America ◽  
North And South

At the turn of the nineteenth and twentieth century a large group of Galician Ruthenians emigrated to North America and the United States and Canada, South America - mainly to Argentina and Brazil. Sheptytsky visited North America in 1910. He met with Ukrainian Greek Catholic immigrant communities in the United States and Canada. In 1921, he visited the USA and Canada again. In 1922 he arrived to Argentina and Brazil. He did not conduct open political agitation. However, some of his speeches have an anti-Polish character.

scholarly journals Genomic Acquisitions in Emerging Populations of Xanthomonas vasicola pv. vasculorum Infecting Corn in the United States and Argentina

2020 ◽  
Vol 110 (6) ◽  
pp. 1161-1173 ◽  
Author(s):  
Alvaro L. Perez-Quintero ◽  
Mary Ortiz-Castro ◽  
Jillian M. Lang ◽  
Adrien Rieux ◽  
Guangxi Wu ◽  
...  
Keyword(s):  
United States ◽  
South America ◽  
Phylogenetic Analyses ◽  
The United States ◽  
Virulence Determinants ◽  
Genetic Changes ◽  
Genomic Changes ◽  
Future Work ◽  
North And South America ◽  
North And South

Xanthomonas vasicola pv. vasculorum is an emerging bacterial plant pathogen that causes bacterial leaf streak on corn. First described in South Africa in 1949, reports of this pathogen have greatly increased in the past years in South America and in the United States. The rapid spread of this disease in North and South America may be due to more favorable environmental conditions, susceptible hosts and/or genomic changes that favored the spread. To understand whether genetic mechanisms exist behind the recent spread of X. vasicola pv. vasculorum, we used comparative genomics to identify gene acquisitions in X. vasicola pv. vasculorum genomes from the United States and Argentina. We sequenced 41 genomes of X. vasicola pv. vasculorum and the related sorghum-infecting X. vasicola pv. holcicola and performed comparative analyses against all available X. vasicola genomes. Time-measured phylogenetic analyses showed that X. vasicola pv. vasculorum strains from the United States and Argentina are closely related and arose from two introductions to North and South America. Gene content comparisons identified clusters of genes enriched in corn X. vasicola pv. vasculorum that showed evidence of horizontal transfer including one cluster corresponding to a prophage found in all X. vasicola pv. vasculorum strains from the United States and Argentina as well as in X. vasicola pv. holcicola strains. In this work, we explore the genomes of an emerging phytopathogen population as a first step toward identifying genetic changes associated with the emergence. The acquisitions identified may contain virulence determinants or other factors associated with the spread of X. vasicola pv. vasculorum in North and South America and will be the subject of future work.

Current Understanding of the History, Global Spread, Ecology, Evolution, and Management of the Corn Bacterial Leaf Streak Pathogen, Xanthomonas vasicola pv. vasculorum

2020 ◽  
Vol 110 (6) ◽  
pp. 1124-1131
Author(s):  
Mary Ortiz-Castro ◽  
Terra Hartman ◽  
Teresa Coutinho ◽  
Jillian M. Lang ◽  
Kevin Korus ◽  
...  
Keyword(s):  
United States ◽  
South Africa ◽  
South America ◽  
The United States ◽  
Molecular Diagnostic ◽  
Diagnostic Tools ◽  
Bacterial Leaf Streak ◽  
Long Distance ◽  
North And South America ◽  
North And South

Bacterial leaf streak of corn, caused by Xanthomonas vasicola pv. vasculorum, has been present in South Africa for over 70 years, but is an emerging disease of corn in North and South America. The only scientific information pertaining to this disease on corn came from work done in South Africa, which primarily investigated host range on other African crops, such as sugarcane and banana. As a result, when the disease was first reported in the United States in 2016, there was very limited information on where this pathogen came from, how it infects its host, what plant tissue(s) it is capable of infecting, where initial inoculum comes from at the beginning of each crop season, how the bacterium spreads from plant to plant and long distance, what meteorological variables and agronomic practices favor disease development and spread, how many other plant species X. vasicola pv. vasculorum is capable of infecting or using as alternate hosts, and if the bacterium will be able to persist in all corn growing regions of the United States. There were also no rapid diagnostic assays available which initially hindered prompt identification prior to the development of molecular diagnostic tools. The goal of this synthesis is to review the history of X. vasicola pv. vasculorum and bacterial leaf streak in South Africa and its movement to North and South America, and highlight the recent research that has been done in response to the emergence of this bacterial disease.

scholarly journals Test of Martin’s overkill hypothesis using radiocarbon dates on extinct megafauna

2015 ◽  
Vol 113 (4) ◽  
pp. 886-891 ◽  
Author(s):  
Todd A. Surovell ◽  
Spencer R. Pelton ◽  
Richard Anderson-Sprecher ◽  
Adam D. Myers
Keyword(s):  
United States ◽  
South America ◽  
The United States ◽  
Small Population ◽  
Ecological Impacts ◽  
Radiocarbon Dates ◽  
Frequency Distributions ◽  
Human Colonization ◽  
North And South America ◽  
North And South

Following Martin [Martin PS (1973) Science 179:969–974], we propose the hypothesis that the timing of human arrival to the New World can be assessed by examining the ecological impacts of a small population of people on extinct Pleistocene megafauna. To that end, we compiled lists of direct radiocarbon dates on paleontological specimens of extinct genera from North and South America with the expectation that the initial decline of extinct megafauna should correspond in time with the initial evidence for human colonization and that those declines should occur first in eastern Beringia, next in the contiguous United States, and last in South America. Analyses of spacings and frequency distributions of radiocarbon dates for each region support the idea that the extinction event first commenced in Beringia, roughly 13,300–15,000 BP. For the United States and South America, extinctions commenced considerably later but were closely spaced in time. For the contiguous United States, extinction began at ca. 12,900–13,200 BP, and at ca. 12,600–13,900 BP in South America. For areas south of Beringia, these estimates correspond well with the first significant evidence for human presence and are consistent with the predictions of the overkill hypothesis.

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