scholarly journals INFINITE DISK AREA CALCULATION EQUATION AND KISAA CONSTANT

2019 ◽  
Keyword(s):  
Disk Area

Disk Area Is a More Reliable Measurement Than Anteroposterior Length in the Assessment of Lumbar Disk Herniations

2020 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Anmol Gupta ◽  
Shivam Upadhyaya ◽  
Caleb M. Yeung ◽  
Peter J. Ostergaard ◽  
Harold A. Fogel ◽  
...  
Keyword(s):  
Reliable Measurement ◽  
Lumbar Disk ◽  
Lumbar Disk Herniations ◽  
Disk Area

Distribution and phenolic composition of sapwood and heartwood in Abiesgrandis and effects of the balsam woolly aphid

1977 ◽  
Vol 7 (1) ◽  
pp. 54-62 ◽  
Author(s):  
George S. Puritch
Keyword(s):  
Western Hemlock ◽  
Annual Rings ◽  
Phenolic Composition ◽  
Aphid Infestation ◽  
Woolly Aphid ◽  
Phenolic Glucoside ◽  
Significant Regression ◽  
Disk Area

The distribution of sapwood and heartwood was analyzed at three different height levels in Abiesgrandis infested and non-infested with balsam woolly aphid. In non-infested trees, there was a highly significant regression between percentage heartwood age and disk age and a less significant regression between percentage heartwood area and disk area. Aphid infestation increased both the number of annual rings of heartwood and the heartwood area. The amount of heartwood in the infested trees was highly variable and dependent upon the degree of aphid infestation. Phenolic composition of A. grandis was similar to western hemlock, with heartwood containing matairesinol, hydroxymatairesinol, conidendrin, and an unknown phenolic glucoside. Sapwood contained several leucoanthocyanidins. Aphid infestation did not alter the phenolic composition of the heartwood, but it did cause the occurrence of a new phenolic in the sapwood. The possible causes of the increased amounts of heartwood in infested trees are discussed.

scholarly journals Infective Potential of Sporangia and Zoospores of Phytophthora ramorum

Plant Disease ◽  
2009 ◽  
Vol 93 (1) ◽  
pp. 30-35 ◽  
Author(s):  
T. L. Widmer
Keyword(s):  
Leaf Area ◽  
Phytophthora Species ◽  
Phytophthora Ramorum ◽  
Inoculum Potential ◽  
Phytophthora Spp ◽  
Zoospore Formation ◽  
Inoculum Type ◽  
Infective Potential ◽  
Disk Area ◽  
Leaf Disks

Phytophthora species produce sporangia that either germinate directly or release zoospores, depending upon environmental conditions. Previous Phytophthora spp. inoculation trials have used both sporangia and zoospores as the inoculum type. However, it is unknown what impact propagule type has on disease. Rhododendron leaf disks were inoculated with P. ramorum zoospores (75, 500, or 2,400 per disk), sporangia (75 per disk), or sporangia plus trifluoperazine hydrochloride (TFP) (75 per disk), a chemical that inhibits zoospore formation. Combining results from two different isolates, the highest concentration of zoospores (2,400 per disk) induced a significantly higher percentage of necrotic leaf disk area (96.6%) than sporangia (87.6%) and 500 zoospores per disk (88.7%). The sporangia plus TFP treatment had the lowest necrosis at 47.5%. Rooted rhododendron cuttings had a higher percentage of necrotic leaves per plant when inoculated with zoospores (3,000 or 50,000 per ml) or cysts (50,000 per ml) than with sporangia (3,000 per ml) with or without TFP. The percentage of necrotic leaf area was significantly higher when cysts or zoospores were inoculated at 50,000 per ml than sporangia without TFP and zoospores at 3,000 per ml. All treatments were significantly higher in the percentage of necrotic leaf area than the leaves treated with sporangia plus TFP. This demonstrates that the full inoculum potential may not be achieved when sporangia are used as the inoculum propagule.

MAXIMUM AREA INDEPENDENT SETS IN DISK INTERSECTION GRAPHS

2010 ◽  
Vol 20 (02) ◽  
pp. 105-118 ◽  
Author(s):  
SERGEY BEREG ◽  
ADRIAN DUMITRESCU ◽  
MINGHUI JIANG
Keyword(s):  
Combinatorial Optimization ◽  
Approximation Algorithms ◽  
Independent Set ◽  
Maximum Independent Set ◽  
Constant Ratio ◽  
Maximum Weight ◽  
Intersection Graphs ◽  
Maximum Area ◽  
Geometric Setting ◽  
Disk Area

Maximum Independent Set (MIS) and its relative Maximum Weight Independent Set (MWIS) are well-known problems in combinatorial optimization; they are NP-hard even in the geometric setting of unit disk graphs. In this paper, we study the Maximum Area Independent Set (MAIS) problem, a natural restricted version of MWIS in disk intersection graphs where the weight equals the disk area. We obtain: (i) Quantitative bounds on the maximum total area of an independent set relative to the union area; (ii) Practical constant-ratio approximation algorithms for finding an independent set with a large total area relative to the union area.

scholarly journals COLONY DEVELOPMENT AND MANAGEMENT OF THE STINGLESS BEE SCAPTOTRIGONA AFF. POSTICA (APIDAE, MELIPONINI) IN DIFFERENT HIVE MODELS

Sociobiology ◽  
2016 ◽  
Vol 63 (4) ◽  
pp. 1038 ◽  
Author(s):  
Kamila Leão Leão ◽  
Ana Carolina Martins De Queiroz ◽  
Jamille Costa Veiga ◽  
Felipe Andrés León Contrera ◽  
Giorgio Cristino Venturieri
Keyword(s):  
Stingless Bee ◽  
The Other ◽  
Colony Development ◽  
Nest Architecture ◽  
Colony Management ◽  
Significant Difference ◽  
Development And Management ◽  
Disk Area

Meliponiculture, i.e. indigenous beekeeping, is an old activity in the Americas and is widely distributed throughout Brazil. However, since stingless bee keeping is still not entirely standardized, studies are necessary to achieve a better practice. For example, the types of hives used in breeding must be designed to ease the colony management and be suitable for each species, once size, behavior, and nest architecture vary among the meliponines. This study aimed to propose and test a vertical hive for breeding Scaptotrigona aff. postica and evaluated characteristics such as colony development and management, comparing it with a horizontal, traditional, hive. Ten colonies of Scaptotrigona sp. were used, five transferred to each hive type tested. During six months, monthly observations of nest components, hive occupation and hive management were made. The brood disk area, contrasting with the other parameters, were about twice larger in the vertical hive. No significant difference in hive occupation was found among the tested models. Management differences were found among the two hive models, where the vertical hive is highlighted having characteristics that eased colony inspection and division, causing minor damage to the nest structures. Thus, this vertical model hive has some advantages for keeping this Scaptotrigona species.

Paleoecology and taxonomy of Schoenaster carterensis, a new encrinasterid ophiuroid species from the Upper Mississippian (Chesterian) Slade Formation of northeastern Kentucky, USA

2020 ◽  
Vol 94 (3) ◽  
pp. 531-547
Author(s):  
Ann W. Harris ◽  
Frank R. Ettensohn ◽  
Jill E. Carnahan-Jarvis
Keyword(s):  
New Species ◽  
Individual Variation ◽  
Feeding Strategy ◽  
Growth Stages ◽  
Middle Mississippian ◽  
Definition Of ◽  
Mississippian Rocks ◽  
Fossil Genus ◽  
Disk Area ◽  
Transitional Environments

AbstractSchoenaster carterensis new species, is an asteroid-like ophiuroid (Echinodermata) from Upper Mississippian (Chesterian) shallow-water carbonates in the Ramey Creek Member of the Slade Formation in northeastern Kentucky. First described in the 1860s from Lower and Middle Mississippian rocks, Schoenaster Meek and Worthen, 1860 is not a well-known fossil genus, but the 39 specimens in this collection permitted further definition of the genus and extended its range by ca. 17 Ma into Late Mississippian (Chesterian) time. The number of specimens also permitted differentiation of growth stages based on average arm length and showed that arm length, disk perimeter, and disk area are interrelated in statistically significant ways. Although replaced by chert, the specimens are nearly intact due to rapid burial as rare constituents in habitat communities distributed among four once-contiguous habitats, including shoal, shoal margin, transitional, and basinal. Most of the ophiuroids were concentrated on firm grounds or hardgrounds in shoal and transitional environments, concentrations that probably reflect substratum stability and the ability to support the ophiuroid's generalist feeding strategy. Many fossil ophiuroid species are known from only a few specimens, severely limiting interpretations about their detailed taxonomy, individual variation, and ecology. In contrast, the greater number of specimens and extensive knowledge of geologic occurrence in this study permitted detailed interpretations regarding the taxonomic, intraspecific, and ecologic attributes of this species, which might be useful in the study of other fossil ophiuroids.UUID: http://www.zoobank.org/ffd945d8-63ac-4c38-a2d3-8647558dbbf0

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