Pollen morphology and taxonomy in North American Labiatae

1992 ◽  
Vol 70 (5) ◽  
pp. 975-995 ◽  
Author(s):  
Marie Claude G. Trudel ◽  
J. K. Morton
Keyword(s):  
North America ◽  
Key Words ◽  
North American ◽  
Pollen Morphology ◽  
Taxonomic Character ◽  
The North ◽  
Primary Basis ◽  
Sem Studies

Pollen morphology is described and illustrated based on SEM studies of 118 species of Labiatae (Lamiaceae) native to North America. These include representatives of all the 36 native genera. Pollen in this family is subspheroidal and either tricolpate (subfamily Lamioideae) or hexacolpate (subfamily Nepetoideae). In most of the genera and species, the tectum is conspicuously perforated with or without a supratectal reticulum. A key to facilitate identification of the pollen of the North American Labiatae is provided. The value of pollen as a taxonomic character in this family is discussed. Pollen provides the primary basis for recognition of subfamilies in the Labiatae, but at the tribal level only the Ajugeae has distinctive pollen. Several genera, notably Collinsonia, Salvia, Teucrium, and Trichostema, have pollen that is very different from other genera in this study. At the infrageneric level pollen provides valuable taxonomic characters in several genera, notably Hyptis, Monardella, Salvia, Stachys, Teucrium, and Trichostema. Key words: Labiatae, Lamiaceae, pollen, SEM, North America.

scholarly journals Philosophy of Education in North America: Where has it been? Where is it going?

2008 ◽  
Vol 8 ◽  
Author(s):  
James Scott Johnston
Keyword(s):  
North America ◽  
Key Words ◽  
North American ◽  
Philosophy Of Education ◽  
Educational Practice ◽  
The North ◽  
Educational Theories

This paper examines the question of philosophy of education’s direction through an examination of its historical self-understandings. The North American, and particularly, U.S. context is highlighted. The thesis is that philosophy of education must reconstruct itself through attention to its past self-understandings, but most importantly, through acceptance of projects, issues, and topics that are relevant to it, and not simply to philosophy or educational practice. Some consequences of this thesis are presented at the end of the paper. Key words: philosophy of education; Dewey's influence; educational theories; historical self-understanding; pragmatism

Studies in the lichen genus Ochrolechia. 2. Corticolous species of North America

1991 ◽  
Vol 69 (4) ◽  
pp. 733-772 ◽  
Author(s):  
Irwin M. Brodo
Keyword(s):  
North America ◽  
Key Words ◽  
North American ◽  
Distribution Maps ◽  
The North ◽  
Group 5 ◽  
Crustose Lichens ◽  
First Time

Ochrolechia, a widespread genus of crustose lichens, includes 19 species growing on bark in North America. These corticolous species and several non-North American taxa are treated in this paper. Six species and one variety are described as new: O. antillarum, O. gowardii, O. montana, O. juvenalis, O. pseudopallescens, O. subisidiata, and O. trochophora var. pruinirosella. Two species are reduced to synonymy (O. californica Vers, and O. sorediosa Howard); six species are excluded from the North American flora (O. alboflavescens (Wulf.) Zahlbr., O. apiculata Vers., O. pallescens (L.) Massal., O. parella (L.) Massal., O. rhamni-purshianae Senft, O. subviridis (Höeg) Erichsen, and O. turneri (Sm.) Hasselrot). Several synonymies mentioned in the literature are confirmed (O. trochophora (Vainio) Oshio including O. rosella (Tuck.) Vers. and O. orientalis Vainio; O. androgyna (Hoffm.) Arn. including O. pergranulosa (Räs.) Vers, and O. mahluensis Räs.; and O. yasudae Vainio including O. tuckermanii Vers, and O. pennsylvanica Vers.). A key for the determination of all the species treated is presented together with distribution maps and a summary of the chemistry of the group. 5-O-Methylhiascic and 4,5-di-O-methylhiascic acids are reported from Ochrolechia for the first time. Key words: Ochrolechia, Ascomycotina, Pertusariaceae.

scholarly journals Progress in Diagnosing Primary Ciliary Dyskinesia: The North American Perspective

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1278
Author(s):  
Michael Glenn O’Connor ◽  
Amjad Horani ◽  
Adam J. Shapiro
Keyword(s):  
Genetic Testing ◽  
North America ◽  
North American ◽  
Primary Ciliary Dyskinesia ◽  
Clinical Phenotype ◽  
The United States ◽  
Diagnostic Process ◽  
The North ◽  
Diagnostic Guideline ◽  
Ciliary Dyskinesia

Primary Ciliary Dyskinesia (PCD) is a rare, under-recognized disease that affects respiratory ciliary function, resulting in chronic oto-sino-pulmonary disease. The PCD clinical phenotype overlaps with other common respiratory conditions and no single diagnostic test detects all forms of PCD. In 2018, PCD experts collaborated with the American Thoracic Society (ATS) to create a clinical diagnostic guideline for patients across North America, specifically considering the local resources and limitations for PCD diagnosis in the United States and Canada. Nasal nitric oxide (nNO) testing is recommended for first-line testing in patients ≥5 years old with a compatible clinical phenotype; however, all low nNO values require confirmation with genetic testing or ciliary electron micrograph (EM) analysis. Furthermore, these guidelines recognize that not all North American patients have access to nNO testing and isolated genetic testing is appropriate in cases with strong clinical PCD phenotypes. For unresolved diagnostic cases, referral to a PCD Foundation accredited center is recommended. The purpose of this narrative review is to provide insight on the North American PCD diagnostic process, to enhance the understanding of and adherence to current guidelines, and to promote collaboration with diagnostic pathways used outside of North America.

New multituberculate mammal from the Early Cretaceous of eastern North America

2013 ◽  
Vol 50 (3) ◽  
pp. 315-323 ◽  
Author(s):  
Richard L. Cifelli ◽  
Cynthia L. Gordon ◽  
Thomas R. Lipka
Keyword(s):  
North America ◽  
Iberian Peninsula ◽  
Early Cretaceous ◽  
North American ◽  
Lower Cretaceous ◽  
Late Jurassic ◽  
Relative Length ◽  
Central Position ◽  
Eastern North America ◽  
The North

Multituberculates, though among the most commonly encountered mammalian fossils of the Mesozoic, are poorly known from the North American Early Cretaceous, with only one taxon named to date. Herein we describe Argillomys marylandensis, gen. et sp. nov., from the Early Cretaceous of Maryland, based on an isolated M2. Argillomys represents the second mammal known from the Arundel Clay facies of the Patuxent Formation (Lower Cretaceous: Aptian). Though distinctive in its combination of characters (e.g., enamel ornamentation consisting of ribs and grooves only, cusp formula 2:4, presence of distinct cusp on anterobuccal ridge, enlargement of second cusp on buccal row, central position of ultimate cusp in lingual row, great relative length), the broader affinities of Argillomys cannot be established because of non-representation of the antemolar dentition. Based on lack of apomorphies commonly seen among Cimolodonta (e.g., three or more cusps present in buccal row, fusion of cusps in lingual row, cusps strongly pyramidal and separated by narrow grooves), we provisionally regard Argillomys as a multituberculate of “plagiaulacidan” grade. Intriguingly, it is comparable in certain respects to some unnamed Paulchoffatiidae, a family otherwise known from the Late Jurassic – Early Cretaceous of the Iberian Peninsula.

A Kinematic Reconstruction of Jurassic ocean spreading from the ophiolites of California, the western U.S. using structural geology and paleomagnetism.

2021 ◽  
Author(s):  
Cemil Arkula ◽  
Nalan Lom ◽  
John Wakabayashi ◽  
Grant Rea-Downing ◽  
Mark Dekkers ◽  
...  
Keyword(s):  
North America ◽  
Relative Position ◽  
North American ◽  
Fault System ◽  
Paleomagnetic Data ◽  
Geochemical Data ◽  
Ophiolite Belt ◽  
The North ◽  
Western Us ◽  
Jurassic Ophiolites

<p>The western edge of the North America plate contains geological records that formed during the long-lived convergence between plates of the Panthalassa Ocean and North America. The geology of different segments along western North America indicates different polarities (eastward and westward) for subducted slabs and thereby various tectonic histories and settings. The western United States (together with Mexico) plays a key role in this debate, many geologic interpretations assume continuous eastward subduction in contrast to observations within proximal geologic segments and tomographic images of the lower mantle below North America and the eastern Pacific Ocean which suggest a more complex subduction history. In this study, we aim to evaluate the plate tectonic setting in which the Jurassic ophiolites of California formed. Geochemical data from these ophiolites suggest that they formed above a nascent intra-oceanic or continental margin subduction zone. We first developed a kinematic reconstruction of the western US geology back to the Jurassic based on published structural geological data. Importantly, we update the reconstruction of the various branches of the San Andreas fault system to determine the relative position of the ophiolite fragments and adopt a previous restoration of Basin and Range extension which we expand northward towards Washington state. We then reconstruct North American margin deformation associated with Cretaceous to Paleogene shortening and strike-slip faulting. We find no clear candidates in the geological record that may have accommodated major subduction between the Jurassic ophiolite belt and the North American margin and consequently concur with the school of thought that considers that the ophiolite belt, as well as the underlying subduction-accretionary Franciscan Complex, likely formed in the North American fore-arc. We collected paleomagnetic data to reconstruct the spreading direction of the Jurassic Californian ophiolites, by providing new paleomagnetic data from sheeted dykes of the Josephine and Mt. Diablo Ophiolites. These suggest a NE-SW paleo-ridge orientation, oblique to the North American margin which may be explained by partitioning of a dextral component of subduction obliquity relative to North America. We used this spreading direction in combination with published ages of the ophiolites and our restoration of the relative position of these ophiolites prior to post-Jurassic deformation to construct a ridge-transform system at which the Jurassic ophiolites accreted. The results will be used to evaluate which parts of the subduction systems that existed in the eastern Panthalassa Ocean may reside in the western US, and which parts may be better sought in the northern Canadian Segment or/and in the southern Caribbean region.</p>

scholarly journals Contrastive Influence of ENSO and PNA on Variability and Predictability of North American Winter Precipitation

2019 ◽  
Vol 32 (19) ◽  
pp. 6271-6284 ◽  
Author(s):  
Xiaofan Li ◽  
Zeng-Zhen Hu ◽  
Ping Liang ◽  
Jieshun Zhu
Keyword(s):  
North America ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
North American ◽  
North Pacific ◽  
Winter Precipitation ◽  
Sea Surface ◽  
The North ◽  
Remote Forcing ◽  
The North Pacific

Abstract In this work, the roles of El Niño–Southern Oscillation (ENSO) in the variability and predictability of the Pacific–North American (PNA) pattern and precipitation in North America in winter are examined. It is noted that statistically about 29% of the variance of PNA is linearly linked to ENSO, while the remaining 71% of the variance of PNA might be explained by other processes, including atmospheric internal dynamics and sea surface temperature variations in the North Pacific. The ENSO impact is mainly meridional from the tropics to the mid–high latitudes, while a major fraction of the non-ENSO variability associated with PNA is confined in the zonal direction from the North Pacific to the North American continent. Such interferential connection on PNA as well as on North American climate variability may reflect a competition between local internal dynamical processes (unpredictable fraction) and remote forcing (predictable fraction). Model responses to observed sea surface temperature and model forecasts confirm that the remote forcing is mainly associated with ENSO and it is the major source of predictability of PNA and winter precipitation in North America.

scholarly journals Novel Highly Pathogenic Avian A(H5N2) and A(H5N8) Influenza Viruses of Clade 2.3.4.4 from North America Have Limited Capacity for Replication and Transmission in Mammals

mSphere ◽  
2016 ◽  
Vol 1 (2) ◽  
Author(s):  
Bryan S. Kaplan ◽  
Marion Russier ◽  
Trushar Jeevan ◽  
Bindumadhav Marathe ◽  
Elena A. Govorkova ◽  
...  
Keyword(s):  
North America ◽  
Avian Influenza ◽  
North American ◽  
Influenza Viruses ◽  
Morbidity And Mortality ◽  
Avian Influenza Viruses ◽  
Highly Pathogenic ◽  
The North ◽  
Domestic Poultry ◽  
The Impact

ABSTRACT Highly pathogenic H5 influenza viruses have been introduced into North America from Asia, causing extensive morbidity and mortality in domestic poultry. The introduced viruses have reassorted with North American avian influenza viruses, generating viral genotypes not seen on other continents. The experiments and analyses presented here were designed to assess the impact of this genetic diversification on viral phenotypes, particularly as regards mammalian hosts, by comparing the North American viruses with their Eurasian precursor viruses. Highly pathogenic influenza A(H5N8) viruses from clade 2.3.4.4 were introduced to North America by migratory birds in the fall of 2014. Reassortment of A(H5N8) viruses with avian viruses of North American lineage resulted in the generation of novel A(H5N2) viruses with novel genotypes. Through sequencing of recent avian influenza viruses, we identified PB1 and NP gene segments very similar to those in the viruses isolated from North American waterfowl prior to the introduction of A(H5N8) to North America, highlighting these bird species in the origin of reassortant A(H5N2) viruses. While they were highly virulent and transmissible in poultry, we found A(H5N2) viruses to be low pathogenic in mice and ferrets, and replication was limited in both hosts compared with those of recent highly pathogenic avian influenza (HPAI) H5N1 viruses. Molecular characterization of the hemagglutinin protein from A(H5N2) viruses showed that the receptor binding preference, cleavage, and pH of activation were highly adapted for replication in avian species and similar to those of other 2.3.4.4 viruses. In addition, North American and Eurasian clade 2.3.4.4 H5NX viruses replicated to significantly lower titers in differentiated normal human bronchial epithelial cells than did seasonal human A(H1N1) and highly pathogenic A(H5N1) viruses isolated from a human case. Thus, despite their having a high impact on poultry, our findings suggest that the recently emerging North American A(H5N2) viruses are not expected to pose a substantial threat to humans and other mammals without further reassortment and/or adaptation and that reassortment with North American viruses has not had a major impact on viral phenotype. IMPORTANCE Highly pathogenic H5 influenza viruses have been introduced into North America from Asia, causing extensive morbidity and mortality in domestic poultry. The introduced viruses have reassorted with North American avian influenza viruses, generating viral genotypes not seen on other continents. The experiments and analyses presented here were designed to assess the impact of this genetic diversification on viral phenotypes, particularly as regards mammalian hosts, by comparing the North American viruses with their Eurasian precursor viruses.

The North American Species in Group X of Ips De Geer (Coleoptera: Scolytidae)

1965 ◽  
Vol 97 (8) ◽  
pp. 803-809 ◽  
Author(s):  
G. R. Hopping
Keyword(s):  
North America ◽  
North American ◽  
North American Species ◽  
The North ◽  
Variable Species ◽  
Ips Calligraphus

AbstractIps calligraphus (Germar), I. ponderosae Swaine and I. interstitialis (Eichhoff) represent one variable species with the oldest name, Ips calligraphus (Germar) taking precedence. Ips calligraphus can always be recognized by the six spines on each side of the declivity. All other species in North America have less than six spines on each side.

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