Comparison of three geographical isolates of Trichinella

1977 ◽  
Vol 55 (12) ◽  
pp. 2060-2064 ◽  
Author(s):  
Michael V. K. Sukhdeo ◽  
Eugene Meerovitch
Keyword(s):  
Reproductive Isolation ◽  
Guinea Pigs ◽  
The Other ◽  
The Arctic ◽  
Infective Larvae ◽  
The North ◽  
White Rats ◽  
Cotton Rats ◽  
Alaskan Arctic ◽  
Geographical Isolates

Isolates of Trichinella from Alaska. Canada, and Kenya were compared in laboratory hosts using three criteria: infectivity, interbreeding, and morphology. It was found that the Canadian (north temperate) isolate had the highest infectivity in the four species of hosts used. The Alaskan (arctic) isolate was less infective to white rats and A/J mice than the Kenyan (tropical) isolate, but the infectivity of the arctic isolate to cotton rats and guinea pigs was similar to that of the tropical isolate. Interbreeding experiments, using single pairs of infective larvae in all isolate combinations in A/J mice, have demonstrated a complete reproductive isolation between the arctic and the other two isolates, and it partial reproductive isolation between the north temperate and tropical isolates, such that the tropical females could not be fertilized by north temperate males nor by north temperate – tropical hydrid males. North temperate adults were found to be longer than those of the other isolates, and so were the uteri of north temperate females. Since the numbers of larvae produced could be dependent on the length of the uterus, infectivity could be a function of uterus size. In fact, a direct correlation was established between the uterus lengths of the three isolates and their respective infectivities in A/J mice. It is concluded that the north temperate, tropical, and arctic isolates most probably correspond to the three species of Trichinella, T. spiralis, T. nelsoni, and T. nativa respectively (Britov.V. A. and S. N. Boev. Vest, Akad. Nauk Kaz. SSR, 28: 27–32 (1972)).

OBSERVATIONS ON EXPERIMENTAL INFECTIONS WITH ECHINOCOCCUS IN RODENTS

1961 ◽  
Vol 39 (6) ◽  
pp. 877-891 ◽  
Author(s):  
Gloria A. Webster ◽  
T. W. M. Cameron
Keyword(s):  
Echinococcus Granulosus ◽  
Echinococcus Multilocularis ◽  
Early Stage ◽  
The Other ◽  
Host Reaction ◽  
Microscopic Anatomy ◽  
Larval Parasite ◽  
Experimental Infections ◽  
White Rats ◽  
Cotton Rats

Experimental infections in rodents with Echinococcus multilocularis sibiricensis, Echinococcus granulosus canadensis, and Echinococcus granulosus (Lebanon origin) both by ingestion of onchospheres and by parenteral injection are recorded. The microscopic anatomy of the larval parasite and of the host reaction are discussed and illustrated in detail. Voles and cotton rats display little resistance to the development of the cyst of E. m. sibiricensis and ultimately destroy the host, while collared lemmings and golden hamsters overcome the cyst and destroy it. Muskrats and certain white mice are intermediate in their effects. In all cases, however, some degree of degeneration of the parasite into the alveolar form is shown. White rats, guinea pigs, and rabbits could not be infected with this parasite. E. g. canadensis was developing in the lung of one AKR strain mouse while in the chinchilla the parasite commenced to develop in the lung but was overcome at an early stage. No development took place in the other species of hosts. E. granulosus (Lebanon) appeared to be developing successfully in some cotton rats and white mice fed on onchospheres.

Atmospheric, oceanic, and sea-ice variability along Nares Strait: a numerical model study

2021 ◽  
Author(s):  
Yarisbel Garcia Quintana ◽  
Paul G. Myers ◽  
Kent Moore
Keyword(s):  
Numerical Model ◽  
Sea Ice ◽  
Arctic Ocean ◽  
North Atlantic ◽  
The Other ◽  
The Arctic ◽  
Nares Strait ◽  
The North ◽  
The Arctic Ocean ◽  
The North Atlantic

<p>Nares Strait, between Greenland and Ellesmere Island, is one of the main pathways connecting the Arctic Ocean to the North Atlantic. The multi-year sea ice that is transported through the strait plays an important role in the mass balance of Arctic sea-ice as well as influencing the climate of the North Atlantic region. This transport is modulated by the formation of ice arches that form at the southern and northern of the strait.  The arches also play an important role in the maintenance of the North Water Polynya (NOW) that forms at the southern end of the strait. The NOW is one of the largest and most productive of Arctic polynyas. Given its significance, we use an eddy-permitting regional configuration of the Nucleus for European Modelling of the Ocean (NEMO) to explore sea-ice variability along Nares Strait, from 2002 to 2019. The model is coupled with the Louvain-la-Neuve (LIM2) sea ice thermodynamic and dynamic numerical model and is forced by the Canadian Meteorological Centre’s Global Deterministic Prediction System Reforecasts.</p><p>We use the model to explore the variability in ocean and sea ice characteristics along Nares Strait. The positive and negative degree days, measures of ice decay and growth, along the strait are consistent with the warming that the region is experiencing. Sea-ice production/decay did not show any significant change other than an enhanced decay during the summers of 2017-1019. Sea-ice thickness on the other hand has decreased significantly since 2007. This decrease has been more pronounced along the northern (north of Kane Basin) portion of the strait. What is more, ocean model data indicates that since 2007 the northern Nares Strait upper 100m layer has become fresher, indicating an increase in the freshwater export out of the Arctic Ocean and through the strait. The southern portion of the strait, on the other hand, has become warmer and saltier, which would be consistent with an influx of Irminger Water as proposed by previous modelling results. These changes could impact the formation and stability of the ice arch and hence the cessation of ice transport down Nares Strait as well as contributing to changes in the characteristics of the NOW. </p>

Russian Flag at the North Pole

2018 ◽  
pp. 410-418
Author(s):  
Rosemary Rayfuse
Keyword(s):  
Continental Shelf ◽  
International Conflict ◽  
North Pole ◽  
The Other ◽  
The Arctic ◽  
Outer Continental Shelf ◽  
The North ◽  
The One ◽  
Legal Sense ◽  
Physical Manifestation

Russia’s planting of a flag on the seabed at the North Pole in 2007 set off a flurry of concern about its maritime and territorial ambitions and the potential for international conflict in the Arctic. However, the law of the sea now renders moot traditional rules of the doctrine of discovery and occupation as manifestations of sovereignty. Thus, the Russian flag at the North Pole is meaningless in the legal sense. Nevertheless, it is not irrelevant. On the one hand, it has catalyzed the development of a ‘law habit’ among the Arctic states now reflected in cooperation on scientific and technical work to support their overlapping outer continental-shelf claims to the Arctic seabed and on other Arctic Ocean matters. On the other hand, it has clearly signalled a claim to an advantageous negotiating position. The flag is thus a physical manifestation of both the power and pretence of international law.

Rights Over the Arctic

1930 ◽  
Vol 24 (4) ◽  
pp. 703-717 ◽  
Author(s):  
W. Lakhtine
Keyword(s):  
North America ◽  
Arctic Ocean ◽  
Far East ◽  
The Other ◽  
The Arctic ◽  
The North ◽  
Arctic Regions ◽  
The Far East ◽  
The Arctic Ocean ◽  
The One

The transarctic flights of 1926 and 1928 demonstrate the possibility of establishing communication by air across the Arctic regions between Europe, on the one side, and North America and the Far East on the other. Quite aside from the saving of time owing to shorter distance, the establishment of such communication presents considerably less diiSculty than air communication over the Atlantic: a conclusion derived from the transatlantic flights of the last three years. The experience of the airship Italia in May, 1928, does not at all nullify this conclusion. It serves merely to show that the organization of transarctic communication requires special prearrangements, such aa wireless stations, meteorological stations, landing-places, air-bases, the construction of which on the shores, islands, and even on the ice of the Arctic Ocean, appears to be quite feasible. The necessity for such stations has aroused in the governments of the North countries an increased interest in the Arctic regions which heretofore has been restricted to scientific circles.

scholarly journals The devil inside that won’t be caged or fixed by words: Fluidity and ethics in Ian McGuire’s The North Water

Ars Aeterna ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 1-23
Author(s):  
Petr Chalupský
Keyword(s):  
Herman Melville ◽  
Medical Doctor ◽  
Cormac Mccarthy ◽  
The Other ◽  
The Arctic ◽  
The Novel ◽  
The North ◽  
Norms And Values ◽  
Heart Of Darkness ◽  
North Water

Abstract In Ian McGuire’s novel The North Water (2016), Patrick Sumner, a young medical doctor recently dismissedfrom the British Army with his reputation and professional prospects in ruins, accepts a poorly paid position as a surgeon on a whaling ship in his attempt to flee from his past and his troubled conscience. However, contrary to his expectations, in the Arctic Circle he faces an ordeal far more demanding than anything he has hitherto endured in the form of the harpooner Henry Drax, a dangerous psychopath who is ready to abuse and murder anyone who is an obstacle to the satisfaction of his brutish physical needs. Confronted with violence and cruelty beyond understanding, within the fluid framework of the distorted ethical norms and values of the heterogeneous crew, the embittered Sumner is gradually forced to abandon his protective shell of resigned indifference and reassess the moral stances and responsibilities of a civilized person when faced with human wickedness. Though McGuire acknowledges primarily the inspiration of Herman Melville and Cormac McCarthy, this paper argues that in ethical terms the novel responds to Joseph Conrad’s Lord Jim and Heart of Darkness, pushing the protagonist’s relationship to the other to an extreme by making the other an embodiment of pure evil.

scholarly journals Connecting European snow cover variability with large scale atmospheric patterns

2010 ◽  
Vol 26 ◽  
pp. 93-97 ◽  
Author(s):  
E. Bartolini ◽  
P. Claps ◽  
P. D'Odorico
Keyword(s):  
Climate Variability ◽  
Snow Cover ◽  
Temporal Variability ◽  
Large Scale ◽  
Management Strategies ◽  
The Other ◽  
The Arctic ◽  
Spatial And Temporal Variability ◽  
East Atlantic ◽  
The North

Abstract. Winter snowfall and its temporal variability are important factors in the development of water management strategies for snow-dominated regions. For example, mountain regions of Europe rely on snow for recreation, and on snowmelt for water supply and hydropower. It is still unclear whether in these regions the snow regime is undergoing any major significant change. Moreover, snow interannual variability depends on different climatic variables, such as precipitation and temperature, and their interplay with atmospheric and pressure conditions. This paper uses the EASE Grid weekly snow cover and Ice Extent database from the National Snow and Ice Data Center to assess the possible existence of trends in snow cover across Europe. This database provides a representation of snow cover fields in Europe for the period 1972–2006 and is used here to construct snow cover indices, both in time and space. These indices allow us to investigate the historical spatial and temporal variability of European snow cover fields, and to relate them to the modes of climate variability that are known to affect the European climate. We find that both the spatial and temporal variability of snow cover are strongly related to the Arctic Oscillation during wintertime. In the other seasons, weaker correlation appears between snow cover and the other patterns of climate variability, such as the East Atlantic, the East Atlantic West Russia, the North Atlantic Oscillation, the Polar Pattern and the Scandinavian Pattern.

scholarly journals Северный идентитет как основа развития традиций в исследовании арктики 1890-1917(Northern identity in Russian and Norwegian cultures as a background for polar explorations 1890-1917)

1998 ◽  
Vol 1 ◽  
pp. 117
Author(s):  
S. A. Xorkina
Keyword(s):  
National Identity ◽  
Nation Building ◽  
Central Place ◽  
The Other ◽  
The Arctic ◽  
Research Activity ◽  
Economic Interests ◽  
The North ◽  
Geographic Factor ◽  
Northern Regions

Compared to other European nations, Norwegians and Russians had an attachment to the Arctic from early on in their history. They were the pioneers in polar seafaring, and the exploration and settlement of the northern regions. For both nations, northernness became an important part of national identity.Northern identity and attachment to the Arctic created the cultural background for both Russian and Norwegian traditions of polar ex- ploration. However, if Norwegian culture confined itself to northernness, the northern identity of the Russians was only one part of a heterogeneous national identity. During the second part of the nineteenth and the beginning of the twentieth centuries the central place of northernness in Norwegian culture and national self-consciousness made polar exploration a natural part of nation-building and promoted Norwegian involvement in the Arctic. For Russia, on the other hand, this period was marked by both decline and reanimation of northern identity. It seems to be that in case of Russia, the geographic factor of the northern identity and political and economic interests in the north were of more importance than cultural predispositions for renewed research activity in the Arctic during the period 1890-1917. At the same time, cultural attributes related to the North were an important part of the Norwegian exploring tradition.

Problems of the Norwegian Church in the Eleventh Century

1935 ◽  
Vol 4 (3) ◽  
pp. 159-172
Author(s):  
Laurence M. Larson
Keyword(s):  
West Coast ◽  
Eleventh Century ◽  
The Other ◽  
The Arctic ◽  
Continuous Series ◽  
The West ◽  
The North ◽  
Scandinavian Peninsula ◽  
Ancient Rock ◽  
Almost Continuous

In Viking times the Northmen recognized several important sea routes, one of which, “the North Way,” was of such significance that it gave its name to a kingdom. The ships that sailed this route followed the west coast of the great Scandinavian peninsula northward and northeastward for a distance of one thousand miles to the land's end in the Arctic. Out toward the sea the fairway is flanked by an almost continuous series of islands, large and small, numbering perhaps one hundred and fifty thousand. Many of these are inhabited. On the other side rises the Norwegian plateau, a massive wall of ancient rock, which in many places descends abruptly to the water's edge. The wall is not continuous, for all along the coast the sea, thrusting forth its mighty arms, has carved out a maze of deep inlets, some of which run far into the land. The longest of these, the Sogn Fjord, has a length of nearly one hundred and forty miles.

Archaeology in the Arctic, 1935-60

1961 ◽  
Vol 27 (1) ◽  
pp. 7-15 ◽  
Author(s):  
Helge Larsen
Keyword(s):  
Coastal Zone ◽  
North American ◽  
Far East ◽  
Central Area ◽  
The Other ◽  
Aleutian Islands ◽  
The Arctic ◽  
Hudson Bay ◽  
The North ◽  
North American Arctic

AbstractArchaeological activities in the North American Arctic are reviewed in terms of the sequences and cultures which have been identified in three major culture areas: the coastal zone from St. Lawrence Island to eastern Greenland, the central area around Hudson Bay with extensions to northern Greenland and Newfoundland, and southwestern Alaska including the Aleutian Islands. Three broad culture horizons are suggested for organizing the data for the first two of these areas. The earliest horizon which cannot be surely identified as either Pre-Eskimo or Proto-Eskimo is tentatively called the Denbigh Flint horizon. It is characterized by fine chipping, micro-cores, micro-blades, burins, and the absence of pottery. These traits occur in the Denbigh Flint and New Mountain complexes and in other assemblages perhaps as far east as the Sarqaq of Greenland. The second or Paleo-Eskimo horizon which also emphasized fine chipping is found in two forms, one with pottery, such as the Choris, Norton, Near Ipiutak, and related cultures in northwestern Canada, and the other without pottery represented by Ipiutak and Dorset. The latest or Neo-Eskimo horizon is the northern maritime tradition of the Okvik to Inugsuk range of cultures. Other approaches to the interpretation of northern archaeology are summarized.

Sphagnum mosses (Sphagnaceae, Bryophyta) of mires Chefandzar and Masota in North Ossetia (Caucasus)

2018 ◽  
Vol 52 (2) ◽  
pp. 455-462 ◽  
Author(s):  
G. Ya. Doroshina ◽  
I. A. Nikolajev
Keyword(s):  
Plant Communities ◽  
The Other ◽  
North Caucasus ◽  
Sphagnum Mosses ◽  
Greater Caucasus ◽  
The North ◽  
First Time ◽  
North Ossetia

Sphagnum mires on the Greater Caucasus are rare, characterized by the presence of relict plant communities of glacial age and are in a stage of degradation. The study of Sphagnum of Chefandzar and Masota mires is carried out for the first time. Seven species of Sphagnum are recorded. Their distribution and frequency within the North Caucasus are analyzed. Sphagnum contortum, S. platyphyllum, S. russowii, S. squarrosum are recorded for the first time for the study area and for the flora of North Ossetia. The other mosses found in the study area are listed.

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