Population and Conservation Genetics of Crawfish Frogs,Lithobates areolatus, at Their Northeastern Range Limit

2013 ◽  
Vol 47 (2) ◽  
pp. 361-368 ◽  
Author(s):  
Schyler O. Nunziata ◽  
Michael J. Lannoo ◽  
Joseph R. Robb ◽  
Daryl R. Karns ◽  
Stacey L. Lance ◽  
...  
2020 ◽  
Vol 86 (1) ◽  
pp. 32-37
Author(s):  
Valeria A. Brodskaya ◽  
Oksana A. Molkova ◽  
Kira B. Zhogova ◽  
Inga V. Astakhova

Powder materials are widely used in the manufacture of electrochemical elements of thermal chemical sources of current. Electrochemical behavior of the powders depends on the shape and size of their particles. The results of the study of the microstructure and particles of the powders of vanadium (III), (V) oxides and lithium aluminate obtained by transmission electron and atomic force microscopy, X-ray diffraction and gas adsorption analyses are presented. It is found that the sizes of vanadium (III) and vanadium (V) oxide particles range within 70 – 600 and 40 – 350 nm, respectively. The size of the coherent-scattering regions of the vanadium oxide particles lies in the lower range limit which can be attributed to small size of the structural elements (crystallites). An average volumetric-surface diameter calculated on the basis of the surface specific area is close to the upper range limit which can be explained by the partial agglomeration of the powder particles. Unlike the vanadium oxide particles, the range of the particle size distribution of the lithium aluminate powder is narrower — 50 – 110 nm. The values of crystallite sizes are close to the maximum of the particle size distribution. Microstructural analysis showed that the particles in the samples of vanadium oxides have a rounded (V2O3) or elongated (V2O5) shape; whereas the particles of lithium aluminate powder exhibit lamellar structure. At the same time, for different batches of the same material, the particle size distribution is similar, which indicates the reproducibility of the technologies for their manufacture. The data obtained can be used to control the constancy of the particle size distribution of powder materials.


2018 ◽  
Vol 17 (2) ◽  
pp. 314 ◽  
Author(s):  
Brian M. Shamblin ◽  
Matthew H. Godfrey ◽  
S. Michelle Pate ◽  
William P. Thompson ◽  
Hope Sutton ◽  
...  

Castanea ◽  
2020 ◽  
Vol 85 (2) ◽  
pp. 232
Author(s):  
Robert G. Laport ◽  
David Smith ◽  
Julienne Ng

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Mohammadi ◽  
K. Almasieh ◽  
D. Nayeri ◽  
F. Ataei ◽  
A. Khani ◽  
...  

AbstractIran lies at the southernmost range limit of brown bears globally. Therefore, understanding the habitat associations and patterns of population connectivity for brown bears in Iran is relevant for the species’ conservation. We applied species distribution modeling to predict habitat suitability and connectivity modeling to identify population core areas and corridors. Our results showed that forest density, topographical roughness, NDVI and human footprint were the most influential variables in predicting brown bear distribution. The most crucial core areas and corridor networks for brown bear are concentrated in the Alborz and Zagros Mountains. These two core areas were predicted to be fragmented into a total of fifteen isolated patches if dispersal of brown bear across the landscape is limited to 50,000 cost units, and aggregates into two isolated habitat patches if the species is capable of dispersing 400,000 cost units. We found low overlap between corridors, and core habitats with protected areas, suggesting that the existing protected area network may not be adequate for the conservation of brown bear in Iran. Our results suggest that effective conservation of brown bears in Iran requires protection of both core habitats and the corridors between them, especially outside Iran’s network of protected areas.


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