Artificial hybridization between Ascophyllum nodosum and Fucus vesiculosus (Phaeophyceae) from Nova Scotia, Canada

1997 ◽  
Vol 75 (7) ◽  
pp. 1133-1136 ◽  
Author(s):  
Kwang Young Kim ◽  
Stephen J. O'Leary ◽  
David J. Garbary

Reciprocal crosses between male and female gametes of Ascophyllum nodosum (L.) LeJolis and Fucus vesiculosus L. were made from plants collected at Tor Bay, Nova Scotia. Crosses within each species were viable and resulted in normal zygote development. Hybrids occurred in low frequency in the cultures (ca. 1–5%) and developed either an initial rhizoid or underwent one or two internal divisions. Hybrid zygotes did not develop further. More developing embryos were observed in crosses when F. vesiculosus provided the eggs, and these zygotes developed longer rhizoids. Maximum development was to three or four cells, which occurred in ca. 10 days. By 5 weeks, all zygotes had disintegrated. Nuclear diameter was the same in both species (6 μm) although almost twice as much nuclear DNA was present in A. nodosum than in F. vesiculosus. Nuclei in hybrids were larger than in the parental species. Key words: Ascophyllum nodosum, Fucus vesiculosus, Fucales, hybridization, Phaeophyta.

1952 ◽  
Vol 30 (1) ◽  
pp. 78-97 ◽  
Author(s):  
Constance MacFarlane

The Nova Scotia Research Foundation is making an extensive survey of seaweeds of the Province that are of potential commercial importance. The area in which the survey has been completed extends from Cape Sable Island, Shelburne County to Chebogue, Yarmouth County, and includes also a small part of Digby County. The survey includes both quantitative measurements and biological studies of fucoids, Laminaria spp., and Chondrus, in all of which the region abounds. Of 325 miles of coastline surveyed for rockweed, 140 miles are harvestable, bearing approximately 200,000 tons. Results obtained at 255 stations, examined in detail, showed the average density to be 37 lb. per sq. yd. The width of the zone is from 2 to 300 yd., the average being 50 yd. Ascophyllum nodosum forms the greatest percentage of rockweed, Fucus vesiculosus ranking next. Fucus serratus is recorded for the first time in this part of the Province. Laminaria beds totalling 12,000 ac. in extent and bearing 900,000 tons were charted. Mortality among Laminaria sporophytes is high and the number in a bed varies from year to year. In 1950 7,997,739 lb. of Chondrus were harvested. Density varies from 1 to [Formula: see text] lb. per sq. ft. Chondrus beds are listed and their ecology discussed. Recolonization of denuded areas is described and succession of algal cover noted on denuded areas and on concrete blocks placed in Chondrus and Laminaria beds. The survey region is compared with regions surveyed in Scotland. A map of the survey region is included.


Author(s):  
Viruja Ummat ◽  
Marco Garcia-Vaquero ◽  
Mahesha M. Poojary ◽  
Marianne N. Lund ◽  
Colm O’Donnell ◽  
...  

AbstractSeaweeds are a valuable potential source of protein, as well as free amino acids (FAAs) with umami flavour which are in high demand by the food industry. The most commonly used flavouring agents in the food industry are chemically synthesised and therefore are subject to concerns regarding their safety and associated consumer resistance. This study focuses on the effects of extraction time (1 and 2 h) and solvents (0.1 M HCl, 1% citric acid and deionised water) on the extraction of protein and FAAs including umami FAAs from Irish brown seaweeds (Ascophyllum nodosum and Fucus vesiculosus). Extraction yields were influenced by both the extraction solvent and time, and also varied according to the seaweed used. Both seaweeds investigated were found to be good sources of protein, FAAs including umami FAAs, demonstrating potential application as flavouring agents in the food industry. Overall, the use of green solvents (deionised water and citric acid) resulted in higher recoveries of compounds compared to HCl. The results of this study will facilitate the use of more sustainable solvents in industry for the extraction of proteins and flavouring agents from seaweed.


Molecules ◽  
2021 ◽  
Vol 26 (3) ◽  
pp. 714
Author(s):  
Enver Keleszade ◽  
Michael Patterson ◽  
Steven Trangmar ◽  
Kieran J. Guinan ◽  
Adele Costabile

Metabolic syndrome (MetS) is a global public health problem affecting nearly 25.9% of the world population characterised by a cluster of disorders dominated by abdominal obesity, high blood pressure, high fasting plasma glucose, hypertriacylglycerolaemia and low HDL-cholesterol. In recent years, marine organisms, especially seaweeds, have been highlighted as potential natural sources of bioactive compounds and useful metabolites, with many biological and physiological activities to be used in functional foods or in human nutraceuticals for the management of MetS and related disorders. Of the three groups of seaweeds, brown seaweeds are known to contain more bioactive components than either red and green seaweeds. Among the different brown seaweed species, Ascophyllum nodosum and Fucus vesiculosus have the highest antioxidant values and highest total phenolic content. However, the evidence base relies mainly on cell line and small animal models, with few studies to date involving humans. This review intends to provide an overview of the potential of brown seaweed extracts Ascophyllum nodosum and Fucus vesiculosus for the management and prevention of MetS and related conditions, based on the available evidence obtained from clinical trials.


1981 ◽  
Vol 71 (5) ◽  
pp. 1649-1659
Author(s):  
Thomas M. Brocher ◽  
Brian T. Iwatake ◽  
Joseph F. Gettrust ◽  
George H. Sutton ◽  
L. Neil Frazer

abstract The pressures and particle velocities of sediment-borne signals were recorded over a 9-day period by an array of telemetered ocean-bottom seismometers positioned on the continental margin off Nova Scotia. The telemetered ocean-bottom seismometer packages, which appear to have been very well coupled to the sediments, contained three orthogonal geophones and a hydrophone. The bandwidth of all sensors was 1 to 30 Hz. Analysis of the refraction data shows that the vertical geophones have the best S/N ratio for the sediment-borne signals at all recording depths (67, 140, and 1301 m) and nearly all ranges. The S/N ratio increases with increasing sensor depth for equivalent weather conditions. Stoneley and Love waves detected on the Scotian shelf (67-m depth) are efficient modes for the propagation of noise.


Author(s):  
Liqin Wu ◽  
Cuihua Xi

Switch cost and cost site have been controversial issues in the code-switching studies. This research conducted an eye tracking experiment on eight bilingual subjects to measure their switch cost and cost site in comprehending the intra-sentential code-switching (Chinese and English) and the unilingual (pure Chinese) stimuli. The English words and their Chinese translations or equivalents were assumed as the key words in either a unilingual or an intra-sentential code-switching paragraph. These key words were located as areas of interest (AOI) with the same height and consisted of three word-frequency levels. After the experiment, the subjects were required to do a comprehension test to ensure their real understanding of the English words. Their performances in two different reading contexts were compared by adopting a paired sample t-test. Their eye movement data were validated by using 2 x 3 repeated measures ANOVA. It was revealed that: 1) the subjects’ scores in the intra-sentential code-switching contexts were higher than those in the unilingual ones, i.e. reading efficiency increased in the intra-sentential code-switching contexts; 2) word frequency had little effect on word recognition speed in the intra-sentential code-switching contexts, i.e., the least frequently used words did not necessarily take the subjects’ more time or vice versa; 3) even if a switch cost occurred(on rare occasions), it was not necessarily at the switching site, and low frequency words in alternating languages did impair performance even when the switch occurred at a sentence boundary.


2021 ◽  
Vol 4 (8) ◽  
pp. e202101102
Author(s):  
Machika Kawamura ◽  
Satoshi Funaya ◽  
Kenta Sugie ◽  
Masataka G Suzuki ◽  
Fugaku Aoki

The pericentromeric heterochromatin of one-cell embryos forms a unique, ring-like structure around the nucleolar precursor body, which is absent in somatic cells. Here, we found that the histone H3 variants H3.1 and/or H3.2 (H3.1/H3.2) were localized asymmetrically between the male and female perinucleolar regions of the one-cell embryos; moreover, asymmetrical histone localization influenced DNA replication timing. The nuclear deposition of H3.1/3.2 in one-cell embryos was low relative to other preimplantation stages because of reduced H3.1/3.2 mRNA expression and incorporation efficiency. The forced incorporation of H3.1/3.2 into the pronuclei of one-cell embryos triggered a delay in DNA replication, leading to developmental failure. Methylation of lysine residue 27 (H3K27me3) of the deposited H3.1/3.2 in the paternal perinucleolar region caused this delay in DNA replication. These results suggest that reduced H3.1/3.2 in the paternal perinucleolar region is essential for controlled DNA replication and preimplantation development. The nuclear deposition of H3.1/3.2 is presumably maintained at a low level to avoid the detrimental effect of K27me3 methylation on DNA replication in the paternal perinucleolar region.


K ta Kita ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 64-70
Author(s):  
Febe Widarma

This study identifed male and female’s cognitive learning styles and found out the differences and similarities the cognitive learning styles between male and female students in grade 10 of “X”school in Surabaya. There were twenty six students in Natural Science class (X-IPA1). The main theory for this study is from Ehrman (1996) about Cognitive Learning Styles. The method was mixed-methods. The researcher distributed questionnaires adapted from Ehrman and Leaver (2002b) ind interview to the students in order to know their cognitive learning styles. The findings showed that male students were concrete and female students were analog learners. Additionally, the finding also showed that the male and female students had five similarities and five differences. English teachers will be easier to conduct classroom activites based on the findings of male and female students’ cognitive learning styles. Key words: Cognitive learning styles, learning style, gender


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