scholarly journals Recent shallow marine Ostracoda of the Ikerssuak (Bredefjord) District, Southwest Greenland

1989 ◽  
Vol 8 (1) ◽  
pp. 55-75 ◽  
Author(s):  
David N. Penney
Keyword(s):  
Primary Production ◽  
Distribution Pattern ◽  
Late Summer ◽  
Similar Distribution ◽  
Western Atlantic ◽  
Shallow Marine ◽  
The Town ◽  
Similar Distribution Pattern ◽  
Ostracod Species ◽  
Southwest Greenland

Abstract. From a study of 15 grab samples collected from the littoral and sublittoral of the Ikerssuak (Bredefjord) district, SW Greenland, one myodocopid and 18 podocopid ostracod species were recovered. These constitute an indigenous fauna and the majority have been recorded from Greenland before. Leptocythere castanea and Leptocythere lacertosa are new to Greenland, and have not previously been confirmed from the western Atlantic. Copulating pairs of Hemicythere borealis were found in an intertidal embayment near the town of Narssaq. This species reproduced just before the late summer-autumn maximum of primary production in the area, and at the warmest time of the year. Semicytherura nigrescens, which has been recorded previously in SW Greenland, may have a similar distribution pattern to certain Subarctic Mollusca in western Greenland.

scholarly journals Neural Differentiation in HDAC1-Depleted Cells Is Accompanied by Coilin Downregulation and the Accumulation of Cajal Bodies in Nucleoli

2017 ◽  
Vol 2017 ◽  
pp. 1-13 ◽  
Author(s):  
Jana Krejčí ◽  
Soňa Legartová ◽  
Eva Bártová
Keyword(s):  
Distribution Pattern ◽  
Neural Differentiation ◽  
Adult Mouse ◽  
Embryonic Stem ◽  
Adult Brain ◽  
Cajal Bodies ◽  
Similar Distribution ◽  
Nuclear Events ◽  
Adult Hippocampus ◽  
Similar Distribution Pattern

Cajal bodies (CBs) are important compartments containing accumulated proteins that preferentially regulate RNA-related nuclear events, including splicing. Here, we studied the nuclear distribution pattern of CBs in neurogenesis. In adult brains, coilin was present at a high density, but CB formation was absent in the nuclei of the choroid plexus of the lateral ventricles. Cells of the adult hippocampus were characterized by a crescent-like morphology of coilin protein. We additionally observed a 70 kDa splice variant of coilin in adult mouse brains, which was different to embryonic brains and mouse pluripotent embryonic stem cells (mESCs), characterized by the 80 kDa standard variant of coilin. Here, we also showed that depletion of coilin is induced during neural differentiation and HDAC1 deficiency in mESCs caused coilin accumulation inside the fibrillarin-positive region of the nucleoli. A similar distribution pattern was observed in adult brain hippocampi, characterized by lower levels of both coilin and HDAC1. In summary, we observed that neural differentiation and HDAC1 deficiency lead to coilin depletion and coilin accumulation in body-like structures inside the nucleoli.

THE BIOLOGY OF CANADIAN WEEDS.: 81. Atriplex patula L., A. prostrata BOUCHER EX DC., AND A. rosea L.

1987 ◽  
Vol 67 (4) ◽  
pp. 1069-1082 ◽  
Author(s):  
I. J. BASSETT ◽  
D. B. MUNRO
Keyword(s):  
Late Summer ◽  
Western Canada ◽  
Similar Distribution ◽  
Weed Biology ◽  
Cape Breton Island ◽  
Cape Breton ◽  
Small Grains ◽  
Annual Weeds ◽  
Pollen Shed ◽  
Similar Distribution Pattern

Atriplex patula L., spreading atriplex, A. prostrata Boucher ex DC., halberd-leaved atriplex, and A. rosea L., red scale, are introduced annual weeds occurring in gardens, fields and orchards in various parts of Canada. Red scale is expanding its range in western Canada where plants are abundant enough in some areas to cause hay fever from large amounts of pollen shed in late summer. Spreading atriplex occurs wide-ranging across Canada, it is rare in western Canada and occurs commonly from southern Ontario to Cape Breton Island; halbred-leafed atriplex has a similar distribution pattern but it occurs commonly throughout its range. Both can be weedy in small grains and gardens.Key words: Atriplex, orache, weed biology

Role of blood pressure in mediating the influence of salt intake on renin expression in the kidney

2012 ◽  
Vol 302 (10) ◽  
pp. F1278-F1285 ◽  
Author(s):  
Katharina Machura ◽  
Björn Neubauer ◽  
Dominik Steppan ◽  
Ramona Kettl ◽  
Andreas Groβ ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Distribution Pattern ◽  
Salt Intake ◽  
Salt Content ◽  
Similar Distribution ◽  
High Salt Intake ◽  
Low Salt ◽  
Afferent Arterioles ◽  
Similar Distribution Pattern

The salt intake of an organism controls the number of renin-producing cells in the kidney by yet undefined mechanisms. This study aimed to assess a possible mediator role of preglomerular blood pressure in the control of renin expression by oral salt intake. We used wild-type (WT) mice and mice lacking angiotensin II type 1a receptors (AT1a−/−) displaying an enhanced salt sensitivity to renin expression. In WT kidneys, we found renin-expressing cells at the ends of all afferent arterioles. A low-salt diet (0.02%) led to a moderate twofold increase in renin-expressing cells along afferent arterioles. In AT1a−/− mice, lowering of salt content led to a 12-fold increase in renin expression. Here, the renin-expressing cells were distributed along the preglomerular vascular tree in a typical distal-to-proximal distribution gradient which was most prominent at high salt intake and was obliterated at low salt intake by the appearance of renin-expressing cells in proximal parts of the preglomerular vasculature. While lowering of salt intake produced only a small drop in blood pressure in WT mice, the marked reduction of systolic blood pressure in AT1a−/− mice was accompanied by the disappearance of the distribution gradient from afferent arterioles to arcuate arteries. Unilateral renal artery stenosis in AT1a−/− mice on a normal salt intake produced a similar distribution pattern of renin-expressing cells as did low salt intake. Conversely, increasing blood pressure by administration of the NOS inhibitor N-nitro-l-arginine methyl ester or of the adrenergic agonist phenylephrine in AT1a−/− mice kept on low salt intake produced a similar distribution pattern of renin-producing cells as did normal salt intake alone. These findings suggest that changes in preglomerular blood pressure may be an important mediator of the influence of salt intake on the number and distribution of renin-producing cells in the kidney.

scholarly journals Differentiated microdomains on the luminal surface of the capillary endothelium. I. Preferential distribution of anionic sites.

1981 ◽  
Vol 90 (3) ◽  
pp. 605-613 ◽  
Author(s):  
N Simionescu ◽  
M Simionescu ◽  
G E Palade
Keyword(s):  
Distribution Pattern ◽  
Capillary Endothelium ◽  
Similar Distribution ◽  
Coated Pits ◽  
Free Aldehyde ◽  
Functional Implications ◽  
Aldehyde Groups ◽  
Similar Distribution Pattern

Cationized ferritin (CF), introduced systemically in vivo or by perfusion in situ, binds preferentially to certain microdomains of the luminal plasmalemma of fenestrated capillaries (mouse pancreas and jejunum). The density and affinity of binding decrease in the following order: fenestral diaphragms greater than coated pits greater than plasmalemma proper. CF binds neither to the membrane of plasmalemmal vesicles and transendothelial channels nor to the corresponding stomatal diaphragms. The distribution pattern is the same when glutaraldehyde fixation precedes the administration of the tracer by perfusion, provided fixation is followed by quenching of residual free aldehyde groups. A much smaller cationic probe (alcian blue) perfused together with the fixative reveals a similar distribution pattern. The functional implications of the association of these microdomains with structures involved in capillary permeability are discussed.

FLUCTUATIONS IN NUMBERS OF ADULT BLACK FLIES (DIPTERA: SIMULIIDAE) IN DEEP RIVER, ONTARIO

1972 ◽  
Vol 104 (9) ◽  
pp. 1465-1470 ◽  
Author(s):  
W. F. Baldwin ◽  
H. P. Gross
Keyword(s):  
Late Summer ◽  
Weather Conditions ◽  
Control Site ◽  
Black Flies ◽  
Small Stream ◽  
Local Species ◽  
Summer Decline ◽  
The Town ◽  
Light Forest ◽  
Control Trap

AbstractAdult black flies were trapped at the townsite of Deep River from the early emergence of Prosimulium spp. (approx. 21 May) through to the late summer decline of Simulium spp. (in August). "Sticky" traps employing CO2 as an attractant were located at five sites throughout the town; in addition a trap was positioned at a "control" site outside the town limits near a heavily forested area. The overall numbers increased rapidly in early June, remaining at high levels until the first week in July, by which time over 110,000 flies had been captured. The numbers of flies recovered both within and outside the town fluctuated widely with weather conditions, seemingly influenced by precipitation. In the town, three centrally located traps captured only half as many adults as two traps near the southerly limits, where a small stream flowed through light forest. The control trap showed that black flies were at least 10 times more plentiful outside Deep River. Three insecticide applications did not have any measurable effect on fly numbers. The predominant local species is Simulium venustum Say.

A calcareous foraminiferal faunule from the upper Albian Viking Formation of the Giroux Lake and Kaybob North fields, northwestern Alberta: implications for regional biostratigraphic correlation

2000 ◽  
Vol 37 (10) ◽  
pp. 1389-1410 ◽  
Author(s):  
C R Stelck ◽  
J A MacEachern ◽  
S G Pemberton
Keyword(s):  
British Columbia ◽  
Facies Analysis ◽  
The West ◽  
General Increase ◽  
Shallow Marine ◽  
Type Section ◽  
Peace River ◽  
Biostratigraphic Correlation ◽  
Alberta Basin ◽  
The Town

Arenaceous foraminifera from the upper Albian Viking Formation and associated strata are recorded and charted from five wells in the northwestern portion of the West Alberta Basin, viz. Gulf Giroux Lake 04-11-66-21W5, Candel Arco Giroux Lake 00/10-05-65-20W5, Pan Am B-1 Giroux 02/10-05-65-20W5, Calstan B.A. Kaybob W 02-28-63-20W5, and Chevron Fox Creek 10-15-62-19W5. An anomalous calcareous foraminiferal component in three Gulf Giroux Lake samples is illustrated. Ichnological, sedimentological, and stratigraphic studies of the Viking Formation strata, based on 26 cored intervals, indicate largely transgressive, shallow-marine deposition in the area. The microfaunal and ichnological assemblages indicate a general increase in salinity toward normal marine conditions. Facies analysis demonstrates the stacking of two shoreface parasequences, truncated by wave-ravinement surfaces. The calcareous foraminifera in the Viking Formation are associated with abundant and diverse arenaceous foraminifera, with arctic affinities that we have used for determining the microfaunal zone positions. Biostratigraphic correlation has been made with a calcareous faunule in the lower part of the Hasler Formation, within the expanded Fort St. John Group, found in the southern portion of the Keg River subbasin, Hudson Hope region, northeastern British Columbia. This helps to resolve the problem of correlating the stratigraphically equivalent Paddy Member at the type section near the town of Peace River, Alberta.

scholarly journals Association Between Estuary Characteristics and Activities of the Critically Endangered Indo-Pacific Humpback Dolphin (Sousa chinensis)

2021 ◽  
Vol 8 ◽  
Author(s):  
Chi-hung Lin ◽  
Hsing-Juh Lin ◽  
Jian-Ping Suen ◽  
Lien-Siang Chou
Keyword(s):  
Primary Production ◽  
Net Primary Production ◽  
River Estuary ◽  
Late Summer ◽  
Critically Endangered ◽  
Physical Factors ◽  
Factors Affecting ◽  
Net Production ◽  
Sousa Chinensis ◽  
Autumn And Winter

The Indo-Pacific humpback dolphin (Sousa chinensis) has been reported to prefer estuary habitats. This study explored the environmental factors affecting a critically endangered population off the coast of Yunlin, Taiwan. We measured dolphin sighting rates and estuary characteristics affected by the watershed, including seven physical factors (watershed rainfall, watershed runoff, estuarine turbidity, pH, salinity, temperature, and dissolved oxygen) and two biological factors (estuarine net primary production and chlorophyll a concentration), at the Hsinhuwei River estuary in Taiwan. Dolphin activity was measured by sighting rate and behavioral indices for feeding and traveling between 2017 and 2018. We observed that when the maximum net production increased alongside rising temperatures in spring, both the dolphin sighting rate and foraging activity increased. This trend was maintained until heavy rainfall or increased river runoff occurred during late summer, which resulted in high turbidity in autumn and winter. Turbidity was significantly negatively correlated with dolphin activity (sighting rate and foraging). Furthermore, we found that dolphin traveling positively correlated with the chlorophyll a concentration and maximum net production factors, which could attract dolphins expecting more abundant prey fish in the estuary supported by the high primary production. This study provides empirical evidence on how estuary characteristics affected by the watershed can affect the sighting rate and behavioral activities of Indo-Pacific humpback dolphins.

Ostracoda in Lake Illawarra: Environmental factors, assemblages and systematics.

1987 ◽  
Vol 38 (6) ◽  
pp. 795 ◽  
Author(s):  
I Yassini ◽  
BG Jones
Keyword(s):  
Environmental Factors ◽  
Distribution Pattern ◽  
Water Depth ◽  
Intertidal Zone ◽  
New South ◽  
Marine Species ◽  
Seagrass Beds ◽  
South Wales ◽  
Lake Illawarra ◽  
Ostracod Species

Major controls of the distribution pattern and abundance of living ostracod populations in Lake Illawarra, a coastal lagoon south of Wollongong, New South Wales, are salinity and the benthic flora. The biocenotic ostracod assemblage from the intertidal zone around Windang Island is a typical, diverse, upper sublittoral, open ocean fauna. The lake entrance channel, which is a transport corridor for marine sediments into the lagoon, has a restricted ostracod biocenose (14 species) but contains an additional 72 species in the diverse thanatocenose resulting from the mixing of estuarine and marine species. Within the lagoon, the benthic flora influences the ostracod distribution pattern with the most diverse assemblage (13 species) occurring in areas covered by seagrasses. Seagrass distribution is, in turn, controlled by water depth, circulation, turbidity and substrate. Estuarine ostracods associated with the seagrass beds can tolerate florally induced fluctuations in pH from 7 to 10 and in dissolved oxygen from 1 mg l-1 to 14 mg l-1. In the deeper parts of the lagoon with a predominantly mud substrate, the ostracod assemblage is dominated by Osticythere reticulata. Most samples retrieved from the most polluted part of the lagoon contained no ostracods. A total of 90 ostracod species and subspecies belonging to 50 genera has been identified; nine species: Cytheralison cosmetics, Callistocythere janiceburrowsae, Callistocythere windangensis, Neocytherideis anneclarkeae, Actinocythereis robustus, Bradleya rectangulata, Procythereis jonesi, Hemicytherura windangensis and Cytheropteron wrighti; and one subspecies, Callistocythere dorsotuberculata paucicostata, are described as new to science.

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