Biodiversity among Festuca (Poaceae) in North America: diagnostic evidence from DELTA and clustering programs, and an INTKEY package for interactive, illustrated identification and information retrieval

1997 ◽  
Vol 75 (9) ◽  
pp. 1527-1555 ◽  
Author(s):  
Susan G. Aiken ◽  
Cheryl L. McJannet ◽  
Laurie L. Consaul ◽  
Michael J. Dallwitz

Biodiversity among taxa of Festuca occurring in North America has been investigated from a revised and illustrated database developed using the DELTA software package. The database includes common names; the place of valid publication of the name; the location of type specimens, when known, and whether we have examined them; synonymy; data on morphology, anatomy, and chromosome number(s); habitat and distribution information; subgeneric classification; taxonomic notes; and more than 200 images. The data are available on the Internet via the World Wide Web (WWW) at http://www.keil.ukans.edu/delta/or by anonymous file transfer protocol (ftp) from ftp.keil.ukans.edu, as natural-language descriptions and as an INTKEY interactive identification and information-retrieval package for MS-Windows. INTKEY and other DELTA programs have been used to assess biodiversity and have supported recognition of several species that have often been placed into synonymy (e.g., Festuca calligera and Festuca earlei), a status change for Festuca idahoensis subsp. roemeri comb.nov., placing Festuca brachyphylla subsp. breviculmis into synonymy with F. brachyphylla subsp. coloradensis, and suggested a taxonomy that is presented in an annotated list. Phenetic and cladistic analyses suggest that the traditional generic limits of Festuca and Lolium should be retained and four subgenera recognized within Festuca, subgg. Festuca, Leucopoa, Schedonorus, and Subulatae, with sects. Subulatae and Obtusae. Key words: DELTA, Festuca, Lolium, Poaceae, biodiversity, WWW, taxonomy.


2006 ◽  
Vol 143 (5) ◽  
pp. 621-634 ◽  
Author(s):  
SUSANNAH C. R. MAIDMENT ◽  
GUANGBIAO WEI

Seven genera of stegosaurian dinosaur have been named on the basis of material from the Upper Jurassic of China, and this represents a diversity of stegosaurs unparalleled around the world at this time. However, many of the original specimens used to diagnose and describe these species are currently unavailable, and the original descriptions and figures are often inadequate. The Chinese stegosaurs have proven ‘unstable’ in the few cladistic analyses of Stegosauria that have been carried out, causing a loss of resolution in cladograms. Supplementary data on previously described specimens are presented here along with a taxonomic revision. Only Tuojiangosaurus multispinus, Chungkingosaurus jiangbeiensis and Gigantspinosaurus sichuanensis are considered to be valid taxa, with autapomorphies pertaining to features of the ilio-sacral blocks and dermal armour in all cases. The holotype specimen of ‘Chialingosaurus kuani’ is a juvenile, bearing no diagnostic characters, and ‘Monkonosaurus lawulacus’ is based on fragmentary and undiagnostic material. ‘Changtusaurus’ and ‘Yingshanosaurus’ have never been described or figured and their whereabouts are unknown, so they are regarded as nomina nuda. This taxonomic revision significantly reduces known stegosaurian diversity worldwide, and shows that the Chinese diversity was similar to that of Europe and North America in the Upper Jurassic. Previously, it had been suggested that the diversity of Chinese stegosaurs indicated an Asian origin for the clade, a claim that cannot now be upheld.



2002 ◽  
Author(s):  
Richard S. Williams ◽  
Jane G. Ferrigno




Libri ◽  
2020 ◽  
Vol 70 (3) ◽  
pp. 227-237
Author(s):  
Mahdi Zeynali-Tazehkandi ◽  
Mohsen Nowkarizi

AbstractEvaluation of information retrieval systems is a fundamental topic in Library and Information Science. The aim of this paper is to connect the system-oriented and the user-oriented approaches to relevant philosophical schools. By reviewing the related literature, it was found that the evaluation of information retrieval systems is successful if it benefits from both system-oriented and user-oriented approaches (composite). The system-oriented approach is rooted in Parmenides’ philosophy of stability (immovable) which Plato accepts and attributes to the world of forms; the user-oriented approach is rooted in Heraclitus’ flux philosophy (motion) which Plato defers and attributes to the tangible world. Thus, using Plato’s theory is a comprehensive approach for recognizing the concept of relevance. The theoretical and philosophical foundations determine the type of research methods and techniques. Therefore, Plato’s dialectical method is an appropriate composite method for evaluating information retrieval systems.



Author(s):  
Christine E. Sheffer ◽  
Abdulmohsen Al-Zalabani ◽  
Andrée Aubrey ◽  
Rasha Bader ◽  
Claribel Beltrez ◽  
...  

Tobacco use is projected to kill 1 billion people in the 21st century. Tobacco Use Disorder (TUD) is one of the most common substance use disorders in the world. Evidence-based treatment of TUD is effective, but treatment accessibility remains very low. A dearth of specially trained clinicians is a significant barrier to treatment accessibility, even within systems of care that implement brief intervention models. The treatment of TUD is becoming more complex and tailoring treatment to address new and traditional tobacco products is needed. The Council for Tobacco Treatment Training Programs (Council) is the accrediting body for Tobacco Treatment Specialist (TTS) training programs. Between 2016 and 2019, n = 7761 trainees completed Council-accredited TTS training programs. Trainees were primarily from North America (92.6%) and the Eastern Mediterranean (6.1%) and were trained via in-person group workshops in medical and academic settings. From 2016 to 2019, the number of Council-accredited training programs increased from 14 to 22 and annual number of trainees increased by 28.5%. Trainees have diverse professional backgrounds and work in diverse settings but were primarily White (69.1%) and female (78.7%) located in North America. Nearly two-thirds intended to implement tobacco treatment services in their setting; two-thirds had been providing tobacco treatment for 1 year or less; and 20% were sent to training by their employers. These findings suggest that the training programs are contributing to the development of a new workforce of TTSs as well as the development of new programmatic tobacco treatment services in diverse settings. Developing strategies to support attendance from demographically and geographically diverse professionals might increase the proportion of trainees from marginalized groups and regions of the world with significant tobacco-related inequities.



2021 ◽  
pp. 1-4
Author(s):  
Mathieu D'Aquin ◽  
Stefan Dietze

The 29th ACM International Conference on Information and Knowledge Management (CIKM) was held online from the 19 th to the 23 rd of October 2020. CIKM is an annual computer science conference, focused on research at the intersection of information retrieval, machine learning, databases as well as semantic and knowledge-based technologies. Since it was first held in the United States in 1992, 28 conferences have been hosted in 9 countries around the world.



1945 ◽  
Vol 49 (410) ◽  
pp. 51-54
Author(s):  
A. Gouge

A Study of the air routes of the world brings out almost at once the fact that some of the most difficult route are also the most attractive. For instance, the North Atlantic route which couples North America with Europe is certainly one of the most difficult in the world, but also by the fact that it couples two of the most densely populated, as well as the most wealthy groups of people in the world, one of the most attractive.



1991 ◽  
Vol 37 (127) ◽  
pp. 388-400 ◽  
Author(s):  
Julian A. Dowdeswell ◽  
Gordon S. Hamilton ◽  
Jon Ove Hagen

AbstractMany glaciers in Svalbard and in other glacierized areas of the world are known to surge. However, the time series of observations required to assess the duration of fast motion is very restricted. Data on active-phase duration in Svalbard come from aerial photographs, satellite imagery, field surveys and airborne reconnaissance. Evidence on surge duration is available for eight Svalbard ice masses varying from 3 to 1250 km2. Worldwide, active-phase duration is recorded for less than 50 glaciers. Few observations are available on high polar ice masses. The duration of the active phase is significantly longer for Svalbard glaciers than for surge-type glaciers in other areas from which data are available. In Svalbard, the active phase may last from 3 to 10 years. By contrast, a surge duration of 1–2 years is more typical of ice masses in northwest North America, Iceland and the Pamirs. Ice velocities during the protracted active phase on Svalbard glaciers are considerably lower than those for many surge-type glaciers in these other regions. Mass is transferred down-glacier more slowly but over a considerably longer period. Svalbard surge-type glaciers do not exhibit the very abrupt termination of the active phase, over periods of a few days, observed for several Alaskan glaciers. The duration of the active phase in Svalbard is not dependent on parameters related to glacier size. The quiescent phase is also relatively long (50–500 years) for Svalbard ice masses. Detailed field monitoring of changing basal conditions through the surge cycle is required from surge-type glaciers in Svalbard in order to explain the significantly longer length of the active phase for glaciers in the archipelago, which may also typify other high polar ice masses. The finding that surge behaviour, in the form of active-phase duration, shows systematic differences between different regions and their environments has important implications for understanding the processes responsible for glacier surges.



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