Development to third-stage larvae occurs in the eggs of Anisakis simplex and Pseudotetranova decipiens (Nematoda, Ascaridoidea, Anisakidae)

1995 ◽  
Vol 52 (S1) ◽  
pp. 134-139 ◽  
Author(s):  
Marianne Køie ◽  
Bjørn Berland ◽  
Michäel D.B. Burt
Keyword(s):  
North Atlantic ◽  
Sea Water ◽  
Anisakis Simplex ◽  
Stage Larva ◽  
Second Stage ◽  
The Third ◽  
The North ◽  
Pseudoterranova Decipiens ◽  
Third Stage ◽  
Tail Tip

Two moults occur during larval development in the eggs of Anisakis simplex (Rudolphi, 1809) and Pseudoterranova decipiens (Krabbe, 1878) from the North Atlantic. Live larvae forced out of eggs in sea water by coverslip pressure shortly before spontaneous hatching were surrounded by the thin cuticle of the first-stage larva. Infective larvae from naturally hatched eggs are loosely ensheathed in the thick cuticle of the second-stage larva. Thus, it is the third-stage larva that emerges from the egg of both species and not the second-stage larva as previously believed. The thin, smooth, fragile cuticle of the first-stage larva remains in the egg. The striated, cocoon-like cuticle of the second-stage larva of A. simplex may increase the buoyancy of the third-stage larva. The tail tip of the cuticle of the second-stage larva of P. decipiens is sticky and adheres the sheathed third-stage larva to the substrate.

Signs of polichnous deformations in microstructures of carbonate rocks of the Katav-Yuryuzan zone of transpression (Southern Urals)

2020 ◽  
pp. 13-21
Author(s):  
A. V. Tevelev ◽  
A. A. Borisenko ◽  
M. I. Erokhina ◽  
S. S. Popov ◽  
I. A. Kosheleva ◽  
...  
Keyword(s):  
Simple Shear ◽  
Carbonate Rocks ◽  
Pure Shear ◽  
Southern Urals ◽  
Second Stage ◽  
The Third ◽  
The North ◽  
Third Stage ◽  
Three Stages ◽  
Two Stages

The Katav-Ivanovsk transpression zone experienced at least two stages of tectonic deformations, and the sequence of deformations was approximately the same throughout the entire zone — from the Bakal-Satka fault in the south to the Suleimsky fault in the north. Three stages of the formation of parageneses were identified. The parageneses of the first and the second stages were formed in a pure shear environment, and the paragenesis of the third stage — in a simple shear environment. There are stylolites (S1) parallel to bedding, and mineral veins (V1) in the paragenesis of the first stage. Paragenesis of the second stage combines stylolites (S2), mineral veins (V2) and intergranular cleavage (S2). In paragenesis of the third stage were distinguished schistosity (S3), milonites (S3), cataclasites, mica packets (SC-textures), and the rotation structures of porphyroblasts.

Euphausiids as intermediate hosts of Anisakis simplex in the St. Lawrence estuary

1998 ◽  
Vol 76 (7) ◽  
pp. 1226-1235 ◽  
Author(s):  
Réjean Hays ◽  
Lena N Measures ◽  
Jean Huot
Keyword(s):  
Anisakis Simplex ◽  
Intermediate Hosts ◽  
Lawrence Estuary ◽  
Second Stage ◽  
The Third ◽  
Third Stage ◽  
Important Intermediate ◽  
Meganyctiphanes Norvegica ◽  
Saguenay River ◽  
St Lawrence Estuary

To determine abundance of larval Anisakis simplex in euphausiids of the St. Lawrence estuary, Meganyctiphanes norvegica and Thysanoessa raschii were collected at seven sites from the mouth of the Saguenay River to Baie des Outardes. Larvae were removed from euphausiids by means of a modified Baermann apparatus filled with a pepsin-HCl digest solution. Abundances of larvae in euphausiids ranged from 0 to 58.2 × 10-5. Larvae (N = 100) were in the third stage (bearing one cuticle) or moulting from the second stage to the third stage (bearing two cuticles). Euphausiids, particularly T. raschii, which represented 98% of the total euphausiids sampled, are important intermediate hosts of A. simplex in the St. Lawrence estuary. These data indicate the importance of the St. Lawrence estuary as an enzootic zone for A. simplex and thus a valuable area to study the biology and the transmission of this parasite.

Morphometric and morphological characteristics for identifying the life stages of Xiphinema bakeri Williams, 1961 (Nematoda: Longidorinae)

1970 ◽  
Vol 48 (4) ◽  
pp. 771-773 ◽  
Author(s):  
Jack R. Sutherland ◽  
T. G. Dunn ◽  
N. Bruce F. Cousens
Keyword(s):  
Morphological Characteristics ◽  
The Body ◽  
Life Stages ◽  
Larval Stages ◽  
Second Stage ◽  
The Third ◽  
Clear Area ◽  
Third Stage ◽  
Tail Shape ◽  
Tail Tip

Several morphometric and morphological characteristics were evaluated to determine their usefulness in identifying the life stages of Xiphinema bakeri. The stages can be identified by length of the body, onchiostylet, and replacement stylet of larvae. These values increase lineally from first-stage larva to adult, and fall into five groups corresponding to the nematodes' four larval stages and adult. Each stage has a specific tail-tip shape, which gradually changes from subacute in the first and second stages to subdigitate in adults. At lower magnifications, the body length and the tail shape, used in combination, are best for identification. First-stage larvae also have the replacement stylet overlapping the stylet extension, distinguishing them from the second stage. Frequently the immature vagina of fourth-stage larvae appears as a clear area in the body; this helps to separate them from the third stage.

scholarly journals Forest recultivation of overburden dumps of the Kingisepp phosphorite field

2021 ◽  
Vol 875 (1) ◽  
pp. 012029
Author(s):  
I S Nedbaev ◽  
E Y Elsukova ◽  
E A Kushnir ◽  
E I Treschevskaya
Keyword(s):  
Community Formation ◽  
North West ◽  
Second Stage ◽  
The Third ◽  
The North ◽  
Tree Layer ◽  
Birch Trees ◽  
Third Stage ◽  
The Russian Federation ◽  
Overburden Dumps

Abstract The article is devoted to the study of the stages of forest recultivation of overburden dumps of the Kingisepp phosphorite field’s breed located in the North-West of the Russian Federation. 5 test areas with a total area of 63.7 hectares were laid to study the different stages of recultivation. In the course of the study, the author’s team identified four conditional stages of the formation of the spruce community of the forest recultivation of overburden dumps breed. The first stage, which has the conditional name ‘10 years’ is newly planted spruce trees on the recultivation territory. The second stage of the formation of the spruce community (‘20 years’) is that the European spruce passes into the stand. The third stage of community formation (‘30 years’) consists in the growth of all plantings to the level of a stand and in the creation of a birch-spruce or spruce-birch forest, since at the age of more than 30 years European spruce in recultivation by itself territories can occupy up to 50% of the stand. At the fourth stage, spruces displace birch trees from the community, remaining almost the only representative of the tree layer.

scholarly journals Palynostratigraphy of the Lower Tertiary volcanics and marine clastic sediments in the southern part of the West Greenland Basin: implications for the timing and duration of the volcanism

1992 ◽  
Vol 154 ◽  
pp. 13-31
Author(s):  
S Piasecki ◽  
L.M Larsen ◽  
A.K Pedersen ◽  
G.K Pedersen
Keyword(s):  
Volcanic Activity ◽  
Volcanic Rocks ◽  
Dinoflagellate Cysts ◽  
East Greenland ◽  
West Greenland ◽  
Second Stage ◽  
The Third ◽  
The North ◽  
Clastic Sediments ◽  
Third Stage

Volcanic rocks, forming hyaloclastites and subaqueous lava flows, were deposited intercalated with clastic sediments in a water-filled basin in West Greenland in the Early Tertiary. Three main stages of basin infilling occurred in the Disko-Nuussuaq area. The distribution of dinoflagellate cysts in the sediments shows that the basin was marine in the first stage and non-marine in the second stage of infilling. In the third stage the basin was displaced towards the south and was marginally marine. The dinoflagellate cysts form a typical mid-Paleocene assemblage which may be correlated with the calcareous nannoplankton (NP) zonation. The stratigraphically lowest investigated localities are coeval with the uppermost part of nannoplankton zone NP4, whereas the overlying localities within the marine basin (first stage) may be correlated with NP5-6. The localities from the non-marine second stage cannot be correlated with the NP zonation because they do not contain dinoflagellate cysts. Localities from the third stage are coeval with NP7-8. Younger volcanics are subaerially deposited. The total known range of the volcanics now falls within the NP3 to NP8 interval, giving a minimum duration for the main plateau-building stage of the volcanism of 4–6 million years. The subaerial basalts have previously been found to be mainly reversely magnetised, with one normally magnetised sequence which can now be stratigraphically correlated with NP4, and thereby identified as anomaly 27. The basalts in East Greenland started erupting during the NP9 zone, so that the volcanic activity in East Greenland largely succeeded that in West Greenland. In relation to the postulated mantle plume in the North Atlantic this means that the volcanic activity started in the peripheral part of the plume and only later switched to the central part.

Development of Skrjabinoclava inornatae (Nematoda: Acuarioidea) in fiddler crabs (Uca spp.) (Crustacea) and Western Willets (Catoptrophorus semipalmatus inornatus) (Aves: Scolopacidae)

1989 ◽  
Vol 67 (12) ◽  
pp. 2893-2901 ◽  
Author(s):  
P. L. Wong ◽  
R. C. Anderson ◽  
Cheryl M. Bartlett
Keyword(s):  
Stage Larva ◽  
Posterior Half ◽  
Fiddler Crabs ◽  
Male And Female ◽  
The Third ◽  
Third Stage ◽  
Recurvirostra Americana ◽  
Chlidonias Niger ◽  
Tail Tip ◽  
Precocious Development

Skrjabinoclava inornatae Wong and Anderson, 1988 from the posterior half of the oesophagus and proventriculus of Western Willets (Catoptrophorus semipalmatus inornatus (Brewster)) developed to the infective third stage in fiddler crabs (Uca spp.) collected in Louisiana, U.S.A. This is the first report of the development of an acuarioid in a decapod. The third-stage larva was characterized by a dorsally bowed caudal end and one small dorsal protuberance and two large dorsally directed spines on the tail tip. The genital primordia were precociously developed in both male and female third-stage larvae. Larvae transferred experimentally to uninfected willets were found in the mucosa of the proventriculus and underwent the first moult less than 3 days and the fourth moult 5 days postinfection. Adult worms occurred mainly in the posterior end of the oesophagus and were mature 15 days postinfection. It is suggested that the rapidity of maturation of the worms in willets may be related to the precocious development of the genital primordia in the third-stage larvae. Marbled Godwits (Limosa fedoa L.) were infected experimentally. American Avocets (Recurvirostra americana Gmelin) and Black Terns (Chlidonias niger (L.)) given larvae did not become infected.

scholarly journals The Chronology of the hillforts of Western Alania according to historical, archive and archaeological materials

2020 ◽  
Vol 164 ◽  
pp. 11015
Author(s):  
Julia Treyman
Keyword(s):  
North Caucasus ◽  
Medieval Architecture ◽  
Second Stage ◽  
The Third ◽  
The North ◽  
Historical Archive ◽  
Third Stage ◽  
Archaeological Materials ◽  
Compositional Patterns

The article is dedicated to revealing historic stages of the development of medieval architecture of Western Alania; systematization of the existing scientific materials connected with the dating of the medieval architectonic and archaeologic legacy of the region; revealing the periodization with defining corresponding cultural and ethnical peculiarities of architecture, compositional patterns and marking the influence of cultural borrowings. During the conducted research we revealed three chronological periods of the development of the architecture of the North Caucasus. At the first stage in the VI-VII c. A. D. appear the first Alan settlements along the western Caucasian part of the Great Silk Way. At the second stage in the VII- first half of the X c. fortifications are built in hillforts; also at this period was formed the three-part planning schemed which followed the principle: a citadel, a fortress, a fortified settlement. At the third stage in the X-XII c. the development of hillfort is performed under the influence of Byzantine Christian topographic traditions.

The Coherence of Mary Barton: Romance, Realism, and Utopia

2015 ◽  
Vol 5 (3) ◽  
pp. 185-200
Author(s):  
Robert Z. Birdwell
Keyword(s):  
Thomas Carlyle ◽  
The Novel ◽  
Second Stage ◽  
The Third ◽  
Third Stage ◽  
Three Stages ◽  
Mode Of Production

Critics have argued that Elizabeth Gaskell's first novel, Mary Barton (1848), is split by a conflict between the modes of realism and romance. But the conflict does not render the novel incoherent, because Gaskell surpasses both modes through a utopian narrative that breaks with the conflict of form and gives coherence to the whole novel. Gaskell not only depicts what Thomas Carlyle called the ‘Condition of England’ in her work but also develops, through three stages, the utopia that will redeem this condition. The first stage is romantic nostalgia, a backward glance at Eden from the countryside surrounding Manchester. The second stage occurs in Manchester, as Gaskell mixes romance with a realistic mode, tracing a utopian drive toward death. The third stage is the utopian break with romantic and realistic accounts of the Condition of England and with the inadequate preceding conceptions of utopia. This third stage transforms narrative modes and figures a new mode of production.

How well do voice-hearing assessment measures capture the positive experiences of individuals?

2019 ◽  
Author(s):  
Lucy Armstrong ◽  
Lorna Hogg ◽  
Pamela Charlotte Jacobsen
Keyword(s):  
Systematic Review ◽  
Lived Experience ◽  
Second Stage ◽  
The Third ◽  
Third Stage ◽  
Hearing Assessment ◽  
Positive Experiences ◽  
Assessment Measures ◽  
Stage 1 ◽  
The Voice

The first stage of this project aims to identify assessment measures which include items on voice-hearing by way of a systematic review. The second stage is the development of a brief framework of categories of positive experiences of voice hearing, using a triangulated approach, drawing on views from both professionals and people with lived experience. The third stage will involve using the framework to identify any positve aspects of voice-hearing included in the voice hearing assessments identified in stage 1.

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