A comparison of the soluble seed proteins of certain Acer species

1971 ◽  
Vol 49 (11) ◽  
pp. 1951-1957 ◽  
Author(s):  
Theodore T. Ziegenfus ◽  
Roy B. Clarkson

Seed proteins of seven taxa of Acer native to eastern North America were obtained by extraction in 2.5% saline buffer, pH 7.0. These were investigated using the techniques of polyacrylamide disc electrophoresis, immunoelectrophoresis, and double diffusion. Groupings indicated by our protein data were compared with groupings by other researchers based on morphological data. The members of the section Saccharina, A. saccharum subsp. saccharum, A. s. subsp. nigrum and A. s. subsp. floridanum, were found to have close protein similarity. A. negundo, thought by several workers to be the most distinct of the maples, was found to have relatively high protein similarity with the members of the section Saccharina. A. rubrum and A. spicatum were shown to have the least protein similarity to the other taxa investigated. There is low protein similarity between these two taxa, however, indicating they are divergent. The traditional placement of A. rubrum and A. saccharinum in the same section was supported by the relatively high protein similarity of these taxa. Data obtained by serological techniques and polyacrylamide disc electrophoresis were found to be complementary. However, polyacrylamide disc electrophoresis was more sensitive in detecting the protein differences among the taxa investigated.

1987 ◽  
Vol 58 (4) ◽  
pp. 119-124 ◽  
Author(s):  
Gail M. Atkinson ◽  
David M. Boore

Abstract A stochastic model of ground motion has been used as a basis for comparison of data and theoretically-predicted relations between mN (commonly denoted by mbLg) and moment magnitude for eastern North America (ENA) earthquakes. mN magnitudes are recomputed for several historical ENA earthquakes, to ensure consistency of definition and provide a meaningful data set. We show that by itself the magnitude relation cannot be used as a discriminant between two specific spectral scaling relations, one with constant stress and the other with stress increasing with seismic moment, that have been proposed for ENA earthquakes.


1986 ◽  
Vol 60 (2) ◽  
pp. 302-326 ◽  
Author(s):  
J. Bowman Bailey

Although past authors have regarded the Carydiidae as a European family, six species of Carydium are reported here from the Devonian of eastern North America. Two of these belong to a single morphocline common in the Hamilton shales; another (Carydium clarkei) is new. Due to lack of well preserved hinges most of these species were earlier placed in Nucula because serrations or striations on dental elements were mistaken for a taxodont dentition.New data require modification of carydiid phylogenies of earlier authors. 1) Two independent pre-Devonian derivations from Lyrodesma are inferred. 2) Noradonta shergoldi, a carydiid-like lyrodesmatid from the Ordovician of Australia, is recognized as an important phyletic link between the Carydiidae and the Lyrodesmatidae. 3) The previous view of three distinct lineages within Carydium is not supported. Anamorphic data suggest as few as two main lineages and show two of the hinge types to be homeomorphic grades appearing separately or within one or the other of the main lineages.Though too young to be directly involved in the early diversification of the Bivalvia, the actinodont, subheterodont, and pseudotaxodont hinge morphologies of Carydium supply models for the origin of heterodont and taxodont hinges. Anamorphic and other evidence suggests that both are iterative types, and fundamental differences between them may be few. Hence, their preeminence as diagnostic criteria among higher taxa is diminished.


1928 ◽  
Vol 60 (3) ◽  
pp. 60-73 ◽  
Author(s):  
W. S. Blatchley

My last general paper on Florida Coleoptera was prepared in the autumn of 1924, and appeared in the Canadian Entomologist for July, 1925. Since that was written my time has been largely devoted to the final preparation and publication of the “Heteroptera of Eastern North America.” During the three years which have elapsed I have spent the winters at Dunedin on the west coast of Florida, but have made three additional collecting trips, of three or four weeks each, to Royal Palm Park. One of these was in December, the other two in March and April. This park comprises an area of 4,000 acres lying in extreme southern Florida, about 40 miles northeast of Cape Sable.


2019 ◽  
Vol 6 (11) ◽  
pp. 191206 ◽  
Author(s):  
Chase Doran Brownstein

The faunal changes that occurred in the few million years before the Cretaceous–Palaeogene extinction are of much interest to vertebrate palaeontologists. Western North America preserves arguably the best fossil record from this time, whereas terrestrial vertebrate fossils from the eastern portion of the continent are usually limited to isolated, eroded postcranial remains. Examination of fragmentary specimens from the American east, which was isolated for the majority of the Cretaceous as the landmass Appalachia, is nonetheless important for better understanding dinosaur diversity at the end of the Mesozoic. Here, I report on two theropod teeth from the Mount Laurel Formation, a lower-middle Maastrichtian unit from northeastern North America. One of these preserves in detail the structure of the outer enamel and resembles the dentition of the tyrannosauroid Dryptosaurus aquilunguis among latest Cretaceous forms in being heavily mediolaterally compressed and showing many moderately developed enamel crenulations. Along with previously reported tyrannosauroid material from the Mt Laurel and overlying Cretaceous units, this fossil supports the presence of non-tyrannosaurid tyrannosauroids in the Campanian–Maastrichtian of eastern North America and provides evidence for the hypothesis that the area was still home to relictual vertebrates through the end of the Mesozoic. The other tooth is assignable to a dromaeosaurid and represents both the youngest occurrence of a non-avian maniraptoran in eastern North America and the first from the Maastrichtian reported east of the Mississippi. This tooth, which belonged to a 3–4 m dromaeosaurid based on size comparisons with the teeth of taxa for which skeletons are known, increases the diversity of the Maastrichtian dinosaur fauna of Appalachia. Along with previously reported dromaeosaurid teeth, the Mt Laurel specimen supports the presence of mid-sized to large dromaeosaurids in eastern North America throughout the Cretaceous.


1953 ◽  
Vol 44 (2) ◽  
pp. 387-393 ◽  
Author(s):  
F. J. Simmonds

Studies are reported on the extent and importance of competition amongst larval and pupal parasites of Oscinella frit.In Ontario, 30–40 per cent. of frit larvae are parasitised by Hexacola in July–August and superparasitism is thus likely. Subsequent attack by Polyscelis may occur, but probably unsuccessfully.Competition between the larval parasites and the pupal ecto-parasites Callitula and Spalangia is generally slight, because the former species is not abundant and the latter tends to select only healthy hosts.Experiments are described to test the inter-relations of the three pupal parasites by exposing puparia of Drosophila melanogaster to two species simultaneously and in sequence.When Callitula and Spalangia are allowed to oviposit simultaneously, the former is more successful when hosts are relatively few, but otherwise the two species are equally successful. When Callitula parasitises puparia recently exposed to Spalangia, equal numbers of the two parasites emerge, but in the reverse experiment Callitula is superior. Callitula is able to parasitise successfully a proportion of puparia already containing Spalangia whatever the age of the latter; mature Spalangia thus attacked are mostly killed.Similar comparisons of Callitula and Spalangia with the endoparasitic Loxotropa show that Loxotropa is inferior to both the others, but that all three show marked avoidance of multiple parasitism.In general, there is little interference between the various species in the parasite complex associated with the frit-fly.The parasite complex associated with the frit-fly appears to be one that is very well balanced, there being little interference between the various species involved. Moreover, when, for any reason, one species does not attain its accustomed degree of parasitism, this is offset by an increase in the numbers of one or more of the other species.


1967 ◽  
Vol 7 (26) ◽  
pp. 206 ◽  
Author(s):  
MC Franklin ◽  
P McInnes ◽  
PK Briggs

Merino wethers of 30 months of age were hand-fed in pens on low-(chaffed wheaten straw), medium-(84 per cent chaffed wheaten straw; 16 per cent chopped lucerne hay), and high-protein roughage (chopped wheaten hay, or 67.5 per cent chaffed wheaten straw : 32.5 per cent chopped lucerne hay) alone, or supplemented with wheat grain at daily or twice-weekly intervals. The experimental period was 26 weeks and emphasis was placed on the number of survivors, changes in body weight, and mean daily roughage intake. Data were also collected on wool production. No sheep survived on the low-protein roughage (LPR-2.7 per cent crude protein (CP) ). Seven out of 16 sheep in the medium-protein roughage group (MPR-5.2 per cent CP) survived for 26 weeks ; six of these, however, died in the following four weeks. All sheep survived on the two high-protein roughage diets (HPR(1) and HPR(2)-7.6 per cent CP). The wheat supplement increased the number of survivors in the LPR and MPR groups. There was no difference between results from the daily and twice-weekly supplemented groups. Mean daily roughage intake of the unsupplemented sheep increased at each level of protein in the roughage. Mean intake of chaffed wheat straw when fed alone was 220 g per sheep per day. The intake of the same straw when fed with chopped lucerne hay increased by 120 g per sheep per day in the group fed MPR, and by 344 g in the group fed HPR(1). The wheat supplement did not increase intake within any roughage group. Roughage intake was significantly decreased on the HPR(2) diet when a wheat supplement was given. Sheep fed HPR(2) grew more clean wool than sheep in the other unsupplemented groups. Differences between mean clean wool weights of daily and twice-weekly supplemented groups within each roughage group were not significant, but differences between the mean pooled wool weights of each supplemented roughage group were significant.


1989 ◽  
Vol 121 (1) ◽  
pp. 27-42 ◽  
Author(s):  
Yves Bousquet

AbstractThe larvae of Pterostichus (Bothriopterus) ohionis Csiki and P. (Gastrellarius) blanchardi Horn are described and compared respectively with the other known larvae of Bothriopterus Chaudoir and Gastrellarius Casey. A key to larvae of 38 species of Pterostichini occurring in eastern North America is presented.


2018 ◽  
Vol 150 (4) ◽  
pp. 495-498
Author(s):  
Donald L. J. Quicke ◽  
Paul D. N. Hebert ◽  
Buntika A. Butcher

AbstractDNA barcode analysis of specimens belonging to the genus Histeromerus Wesmael, 1838 (Hymenoptera: Braconidae) reveals the presence of two species in North America. One is identified as H. canadensis Ashmead, 1891, which is widely recorded in North America, while the other is H. mystacinus Wesmael, 1838, a species formerly known only from the western Palaearctic.


1978 ◽  
Vol 18 (94) ◽  
pp. 675 ◽  
Author(s):  
S Abu-Serewa

The performance of two groups of pullets reared on either high or low-protein diets was compared under six feeding regimes from 20 to 68 weeks of age. Pullets fed the low-protein (10 per cent) diet from 4 to 20 weeks ate about 20 per cent less food during rearing, were significantly lighter at 20 weeks and were delayed in attaining maturity compared with pullets reared on the high-protein diet. In the period from 20 to 36 weeks of age, pullets reared on the high protein diet laid at a higher rate when fed a laying diet containing 17 per cent protein than with a diet containing 15 per cent protein supplemented with methionine, or 13 per cent protein supplemented with methionine and lysine to the N.R.C. (1971) levels. In contrast, pullets reared on the low-protein diet laid fewer eggs on the 17 per cent protein diet than on the other two diets during the same period. However, no significant rearing x laying interaction was observed in average rate of lay during the whole laying year. The low-protein group laid fewer eggs from 20 to 68 weeks than the other group of birds, but the difference in production was not significant when calculated from maturity. Average rate of lay was not affected by the level of protein in the laying diet, but egg size tended to increase with increasing the level of protein. Increasing the level of protein gradually with the advance in lay had no effect on performance relative to birds fed the 15 or 17 per cent protein diet throughout lay. Restricting the feed intake during lay to 94 per cent of that consumed by full-fed controls, or restricting the time of feeding to four hours daily, reduced egg production by 7 and 6 per cent respectively, regardless of the rearing treatment. Rate of mortality throughout the experiment was not affected by any of the rearing or laying treatments. The results of this experiment indicate that the requirement during lay of pullets reared on a low-protein diet is between 51 and 53 g protein and 900 and 1000 mg of methionine per 4.1 9 MJ (1000 Kcal) ME. This protein concentration should be increased to between 58 and 60 g protein per 4.19 MJ ME if the pullets were reared on conventional diets. Restricting feeding during lay by either of the methods used in this experiment is detrimental to egg production.


1954 ◽  
Vol 11 (6) ◽  
pp. 904-932 ◽  
Author(s):  
Vadim D. Vladykov

For the present study about 300 specimens have been examined. These specimens belong to the six species of chars: C. namaycush, S. fontinalis, S. aureolus, S. oquassa, S. marstoni, and S. alpinus. Among meristic characters, the number of pyloric caeca was found to be very important. Body proportions and meristic characters, such as fin rays and vertebrae, are inadequate to properly describe a species. On the other hand, the skull bones, different teeth, and skeleton of the tail are sufficient in themselves to define a species. The pearl organs were found only in C. namaycush of both sexes. The taxonomic relation between species is as follows: C. namaycush belongs to a distinct genus; S. fontinalis represents a subgenus Baione; while the remaining chars are grouped in a subgenus Salvelinus.


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