scholarly journals Population Genomic Analyses Reveal Connectivity via Human-Mediated Transport across Populus Plantations in North America and an Undescribed Subpopulation of Sphaerulina musiva

2020 ◽  
Vol 33 (2) ◽  
pp. 189-199 ◽  
Author(s):  
J. F. Tabima ◽  
K. L. Søndreli ◽  
S. Keriö ◽  
N. Feau ◽  
M. L. Sakalidis ◽  
...  
Keyword(s):  
United States ◽  
British Columbia ◽  
North America ◽  
North American ◽  
Plant Pathogens ◽  
Evolutionary Dynamics ◽  
Population Genomics ◽  
Plant Domestication ◽  
North American Population ◽  
The North

Domestication of plant species has affected the evolutionary dynamics of plant pathogens in agriculture and forestry. A model system for studying the consequences of plant domestication on the evolution of an emergent plant disease is the fungal pathogen Sphaerulina musiva. This ascomycete causes leaf spot and stem canker disease of Populus spp. and their hybrids. A population genomics approach was used to determine the degree of population structure and evidence for selection on the North American population of S. musiva. In total, 122 samples of the fungus were genotyped identifying 120,016 single-nucleotide polymorphisms after quality filtering. In North America, S. musiva has low to moderate degrees of differentiation among locations. Three main genetic clusters were detected: southeastern United States, midwestern United States and Canada, and a new British Columbia cluster (BC2). Population genomics suggest that BC2 is a novel genetic cluster from central British Columbia, clearly differentiated from previously reported S. musiva from coastal British Columbia, and the product of a single migration event. Phenotypic measurements from greenhouse experiments indicate lower aggressiveness of BC2 on Populus trichocarpa. In summary, S. musiva has geographic structure across broad regions indicative of gene flow among clusters. The interconnectedness of the North American S. musiva populations across large geographic distances further supports the hypothesis of anthropogenic-facilitated transport of the pathogen.

A New Gunnel, Pholis clemensi, from the Coast of Western North America

1964 ◽  
Vol 21 (5) ◽  
pp. 933-939 ◽  
Author(s):  
Richard H. Rosenblatt
Keyword(s):  
British Columbia ◽  
New Species ◽  
North America ◽  
North American ◽  
North American Species ◽  
Western North America ◽  
The North ◽  
The Family ◽  
Juan De Fuca ◽  
A New Species

A new species, Pholis clemensi, referred to the family Pholidae, is named and described from 12 specimens taken in southern British Columbia waters and the Strait of Juan de Fuca. Pholis clemensi is compared with other members of the genus, and a key is given to the North American species.

scholarly journals Verification of Extratropical Cyclones within the NCEP Operational Models. Part I: Analysis Errors and Short-Term NAM and GFS Forecasts

2009 ◽  
Vol 24 (5) ◽  
pp. 1173-1190 ◽  
Author(s):  
Michael E. Charles ◽  
Brian A. Colle
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
Eastern Pacific ◽  
Extratropical Cyclones ◽  
Global Forecast System ◽  
Eastern United States ◽  
Forecast System ◽  
Short Term ◽  
The North

Abstract This paper verifies extratropical cyclones around North America and the adjacent oceans within the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) and North American Mesoscale (NAM) models during the 2002–07 cool seasons (October–March). The analyzed cyclones in the Global Forecast System (GFS) model, North American Mesoscale (NAM) model, and the North American Regional Reanalysis (NARR) were also compared against sea level pressure (SLP) observations around extratropical cyclones. The GFS analysis of SLP was clearly superior to the NAM and NARR analyses. The analyzed cyclone pressures in the NAM improved in 2006–07 when its data assimilation was switched to the Gridpoint Statistical Interpolation (GSI). The NCEP GFS has more skillful cyclone intensity and position forecasts than the NAM over the continental United States and adjacent oceans, especially over the eastern Pacific, where the NAM has a large positive (underdeepening) bias in cyclone central pressure. For the short-term (0–60 h) forecasts, the GFS and NAM cyclone errors over the eastern Pacific are larger than the other regions to the east. There are relatively large biases in cyclone position for both models, which vary spatially around North America. The eastern Pacific has four to eight cyclone events per year on average, with errors >10 mb at hour 48 in the GFS; this number has not decreased in recent years. There has been little improvement in the 0–2-day cyclone forecasts during the past 5 yr over the eastern United States, while there has been a relatively large improvement in the cyclone pressure predictions over the eastern Pacific in the NAM.

HEMITHEA AESTIVARIA IN BRITISH COLUMBIA: CHARACTERS OF A PALAEARCTIC GENUS AND SPECIES NOT PREVIOUSLY KNOWN FROM NORTH AMERICA (LEPIDOPTERA: GEOMETRIDAE: GEOMETRINAE)

1979 ◽  
Vol 111 (10) ◽  
pp. 1121-1126 ◽  
Author(s):  
K.B. Bolte ◽  
Eugene Munroe
Keyword(s):  
British Columbia ◽  
North America ◽  
North American ◽  
Palaearctic Species ◽  
The North

AbstractThe palaearctic species Hemithea aestivaria (Hübner) (Lepidoptera: Geometridae: Geometrinae: Hemitheini), newly reported from British Columbia, is described, discussed and illustrated. The genus and species are new to the North American fauna.

scholarly journals The North American Lightning Detection Network (NALDN)—Analysis of Flash Data: 2001–09

2011 ◽  
Vol 139 (5) ◽  
pp. 1305-1322 ◽  
Author(s):  
Richard E. Orville ◽  
Gary R. Huffines ◽  
William R. Burrows ◽  
Kenneth L. Cummins
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
The United States ◽  
The North ◽  
Lightning Detection ◽  
Geographical Regions ◽  
Positive Peak ◽  
The U.S ◽  
Cg Lightning

Cloud-to-ground (CG) lightning data have been analyzed for the years 2001–09 for North America, which includes Alaska, Canada, and the lower 48 U.S. states. Flashes recorded within the North American Lightning Detection Network (NALDN) are examined. No corrections for detection efficiency variability are made over the 9 yr of the dataset or over the large geographical area comprising North America. There were network changes in the NALDN during the 9 yr, but these changes have not been corrected for nor have the recorded data been altered in any way with the exception that all positive lightning reports with peak currents less than 15 kA have been deleted. Thus, the reader should be aware that secular changes are not just climatological in nature. All data were analyzed with a spatial resolution of 20 km. The analyses presented in this work provide a synoptic view of the interannual variability of lightning observations in North America, including the impacts of physical changes in the network during the 9 yr of study. These data complement and extend previous analyses that evaluate the U.S. NLDN during periods of upgrade. The total (negative and positive) flashes for ground flash density, the percentage of positive lightning, and the positive flash density have been analyzed. Furthermore, the negative and positive first stroke peak currents and the flash multiplicity have been examined. The highest flash densities in Canada are along the U.S.–Canadian border (1–2 flashes per square kilometer) and in the United States along the Gulf of Mexico coast from Texas through Florida (exceeding 14 flashes per square kilometer in Florida). The Gulf Stream is “outlined” by higher flash densities off the east coast of the United States. Maximum annual positive flash densities in Canada range primarily from 0.01 to 0.3 flashes per square kilometer, and in the United States to over 0.5 flashes per square kilometer in the Midwest and in the states of Louisiana and Mississippi. The annual percentage of positive lightning to ground varies from less than 2% over Florida to values exceeding 25% off the West Coast, Alaska, and the Yukon. A localized maximum in the percentage of positive lightning in the NALDN occurs in Manitoba and western Ontario, just north of North Dakota and Minnesota. When averaged over North America, first stroke negative median peak currents range from 19.8 kA in 2001 to 16.0 kA in 2009 and for all years, average 16.1 kA. First stroke positive median peak currents range from a high of 29.0 kA in 2008 and 2009 to a low of 23.3 kA in 2003 with a median of 25.7 kA for all years. There is a relatively sharp transition from low to high median negative peak currents along the Gulf and Atlantic coasts of the United States. No sharp transitions are observed for the median positive peak currents. Relatively lower positive peak currents occur throughout the southeastern United States. The highest values of mean negative multiplicity exceed 3.0 strokes per flash in the NALDN with some variation over the 9 yr. Lower values of mean negative multiplicity occur in the western United States. Positive flash mean multiplicity is slightly higher than 1.1, with the highest values of 1.7 observed in the southwestern states. As has been noted in prior research, CG lightning has significant variations from storm to storm as well as between geographical regions and/or seasons and, consequently, a single distribution for any lightning parameter, such as multiplicity or peak current, may not be sufficient to represent or describe the parameter.

scholarly journals A Surface Wind Extremes (“Wind Lulls” and “Wind Blows”) Climatology for Central North America and Adjoining Oceans (1979–2012)

2015 ◽  
Vol 54 (3) ◽  
pp. 643-657 ◽  
Author(s):  
Jonny W. Malloy ◽  
Daniel S. Krahenbuhl ◽  
Chad E. Bush ◽  
Robert C. Balling ◽  
Michael M. Santoro ◽  
...  
Keyword(s):  
United States ◽  
North America ◽  
North American ◽  
North Atlantic Ocean ◽  
Grid Point ◽  
Surface Wind ◽  
Wind Speeds ◽  
The North ◽  
Anomalous Wind

AbstractThis study explores long-term deviations from wind averages, specifically near the surface across central North America and adjoining oceans (25°–50°N, 60°–130°W) for 1979–2012 (408 months) by utilizing the North American Regional Reanalysis 10-m wind climate datasets. Regions where periods of anomalous wind speeds were observed (i.e., 1 standard deviation below/above both the long-term mean annual and mean monthly wind speeds at each grid point) were identified. These two climatic extremes were classified as wind lulls (WLs; below) or wind blows (WBs; above). Major findings for the North American study domain indicate that 1) mean annual wind speeds range from 1–3 m s−1 (Intermountain West) to over 7 m s−1 (offshore the East and West Coasts), 2) mean durations for WLs and WBs are high for much of the southeastern United States and for the open waters of the North Atlantic Ocean, respectively, 3) the longest WL/WB episodes for the majority of locations have historically not exceeded 5 months, 4) WLs and WBs are most common during June and October, respectively, for the upper Midwest, 5) WLs are least frequent over the southwestern United States during the North American monsoon, and 6) no significant anomalous wind trends exist over land or sea.

Incidence of SCN-Assoicated Gene Mutations in Severe Congenital Neutropenia Patients in North America

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3553-3553
Author(s):  
Jun Xia ◽  
Audrey Anna Bolyard ◽  
Elin Rodger ◽  
Steven Stein ◽  
Andrew AG Aprikyan ◽  
...  
Keyword(s):  
North America ◽  
North American ◽  
Barth Syndrome ◽  
North American Population ◽  
Compound Heterozygous ◽  
Severe Congenital Neutropenia ◽  
Congenital Neutropenia ◽  
Cyclic Neutropenia ◽  
The North ◽  
Two Samples

Abstract Severe congenital neutropenia is a genetically heterogeneous syndrome associated with mutations in several different genes including ELA2, HAX1, GFI1, WAS, and CSF3R. The goal of this study was to define the mutation frequency of these genes in the North American SCN patient population. We also sequenced SBDS, since mutations of SBDS have been associated with congenital and acquired neutropenia. A total of 159 patients were identified in the North American Severe Chronic Neutropenia International Registry (SCNIR) for whom informed consent and genomic DNA samples adequate for sequencing were available. To accommodate our semi-automated high-throughput sequencing pipeline, 94 samples were chosen for sequencing. Since ELA2 sequencing had already been performed in most cases, preference was given to those samples without known ELA2 mutation. Among the samples, 73 were from patients with SCN, 4 with cyclic neutropenia, 10 with idiopathic neutropenia, 2 with Shwachman-Diamond Syndrome (SDS), and 3 with Barth syndrome. Two samples were excluded because of poor sequence quality. Singleton cases with validated mutations of GFI1 (N382S) and WAS (L270P) were observed. The N382S GFI1 mutation was associated with striking monocytosis. A novel nonsense mutation of GFI1 (R412X) was detected in one additional case. As expected, compound heterozygous mutations of SBDS were present in the two cases of SDS. In addition, heterozygous mutations of SBDS (84Cfs3X and Q94X) were observed in two cases of SCN. Typical truncation mutations of CSF3R were detected in 4 cases, all developing MDS or AML. Surprisingly, no mutations of HAX1 were detected. Considering only patients with a diagnosis of SCN who were from North America (125 of the total 159 cases), the incidence of ELA2 mutations was 68%. Eleven novel ELA2 mutations were identified. In 28.8% of cases, no mutation of any gene were detected. Based on these data, we recommend that ELA2 genotyping be performed in all patients with suspected SCN. In the North American population mutations in HAX1, GFI1, SBDS, and WAS are rare and routine genotyping is not indicated. Finally, the data suggest that there are yet undiscovered genetic causes of SCN.

scholarly journals Fungus Causing White-Nose Syndrome in Bats Accumulates Genetic Variability in North America with No Sign of Recombination

mSphere ◽  
2017 ◽  
Vol 2 (4) ◽  
Author(s):  
Jigar Trivedi ◽  
Josianne Lachapelle ◽  
Karen J. Vanderwolf ◽  
Vikram Misra ◽  
Craig K. R. Willis ◽  
...  
Keyword(s):  
North America ◽  
North American ◽  
Disease Ecology ◽  
Spontaneous Mutation ◽  
North American Population ◽  
Pseudogymnoascus Destructans ◽  
Clonal Population ◽  
White Nose Syndrome ◽  
The North ◽  
Single Clone

ABSTRACT Emerging fungal diseases of wildlife are on the rise worldwide, and the white-nose syndrome (WNS) epidemic in North American bats is a catastrophic example. The causal agent of WNS is a single clone of the fungus Pseudogymnoascus destructans. Early evolutionary change in this clonal population has major implications for disease ecology and conservation. Accumulation of variation in the fungus through mutation, and shuffling of variation through recombination, could affect the virulence and transmissibility of the fungus and the durability of what appears to be resistance arising in some bat populations. Our genome-wide analysis shows that the clonal population of P. destructans has expanded in size from a single genotype, has begun to accumulate variation through mutation, and presents no evidence as yet of genetic exchange among individuals. IMPORTANCE Since its discovery in 2006, the emerging infectious disease known as white-nose syndrome has killed millions of bats in North America, making it one of the most devastating wildlife epidemics in recorded history. We demonstrate that there has been as yet only spontaneous mutation across the North American population of P. destructans, and we find no indication of recombination. Thus, selective forces, which might otherwise impact pathogenic virulence, have so far had essentially no genetic variation on which to act. Our study confirmed the time of origin for the first and, thus far, only introduction of P. destructans to North America. This system provides an unprecedented opportunity to follow the evolution of a host-pathogen interaction unfolding in real time.

Trametes gibbosa (Basidiomycetes, Polyporales) in the USA and Canada

2007 ◽  
Vol 85 (3) ◽  
pp. 342-346 ◽  
Author(s):  
J. Kout ◽  
J. Vlasák
Keyword(s):  
United States ◽  
Czech Republic ◽  
North America ◽  
Mating Type ◽  
North American ◽  
Eastern North America ◽  
The Czech Republic ◽  
The North ◽  
The Usa ◽  
First Time

The polypore Trametes gibbosa (Pers.) Fries, common in Europe and Asia, is reported from eastern North America for the first time. Single basidiospore cultures from Pennsylvania, United States, and Quebec, Canada, were paired with each other and with cultures from the Czech Republic. The North American intercollection crosses were 60% compatible and 100% compatible with the Czech cultures. All the crosses among the Czech cultures were 100% compatible. The recent introduction of T. gibbosa to North America is suggested as a possible explanation for the limited number of mating-type alleles and subsequent incompatibility among the North American cultures.

A contribution to the taxonomy of the Naididae (Oligochaeta) of North America

1983 ◽  
Vol 61 (10) ◽  
pp. 2307-2312 ◽  
Author(s):  
R. O. Brinkhurst ◽  
R. D. Kathman
Keyword(s):  
British Columbia ◽  
North America ◽  
North American ◽  
Valid Species ◽  
The North

Some specimens of Chaetogaster diastrophus may have dorsal seatae; there is no need for the separation of such individuals under the name Pseudochaetogaster longmeri. Amphichaeta leydigii and A. americana are recorded and Homochaeta raptisae is transferred to this genus. The source of the confusion between Vejdovskyella comata and V. intermedia is identified and both are now accepted as valid species and are recorded from Washington and British Columbia, respectively. Vejdovskyella hellei is transferred to Specaria. The distinction between Nais communis and N. variabilis is documented, and the serrate nature of the hair setae of N. elinguis is newly described. Pristina idrensis is new to the Canadian fauna; P. aequiseta is new to British Columbia and Washington. The few remaining differences between our records and those presented by other workers are catalogued, yielding a total of 65 confirmed species and two probable additions to the North American fauna.

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