An ecological approach to anatomical variation in Clathromorphum circumscriptum (Rhodophyta, Cryptonemiales)

1980 ◽  
Vol 58 (12) ◽  
pp. 1319-1326
Author(s):  
L. Gendron ◽  
A. Cardinal
Keyword(s):  
Anatomical Variation ◽  
Principal Component ◽  
Anatomical Variations ◽  
Total Sample ◽  
Plastic Response ◽  
Morphometric Characters ◽  
Lawrence Estuary ◽  
Small Cell Size ◽  
Geographic Gradient ◽  
St Lawrence Estuary

Anatomical variations in Clathromorphum circumscriptum collected at various levels and stations in the lower St. Lawrence Estuary were studied, using principal-component analysis performed on the correlation matrix of 12 morphometric characters. The first principal component, which accounted for 30.8% of total sample variance, was associated with variations following a bathymetric gradient. The continuous nature of the variations described could be attributable to a plastic response of the algae.The second principal component, which accounted for 20% of total variance, was not associated with variations following a geographic gradient as it may have been expected. However, samples from one station separated from others by having shorter cells. A causal relationship between the low spring and fall salinities recorded at this station and small cell size is suspected.With regard to the relation found between anatomical variations and the bathymetric gradient, interspecific relations within the genus Clathromorphum are examined.

Distribution des spectres de taille des particules en suspension dans le fjord du Saguenay

1979 ◽  
Vol 16 (2) ◽  
pp. 240-249 ◽  
Author(s):  
J. P. Chanut ◽  
S. A. Poulet
Keyword(s):  
Particle Size ◽  
Water Mass ◽  
Layer Structure ◽  
Principal Component ◽  
Water Masses ◽  
Size Spectra ◽  
Lawrence Estuary ◽  
Saguenay Fjord ◽  
Bottom Waters ◽  
St Lawrence Estuary

The spatial distribution of particle size spectra shows a two-layer stratification in May but reveals three-layer structure in September, both in the Saguenay fjord and in the adjacent waters of the St. Lawrence estuary, near the sill. In May, the particle size spectra in the surface layer show considerable variability whereas, in the bottom waters, they appear to be relatively homogeneous. In September, the deeper, more homogeneous water mass is less extensive. It is apparently eroded by diffusion and advection during summer months and becomes restricted to intermediate depths towards the head of the fjord. During the same period, a water mass with physical and particulate properties different from the upper layers occupies the bottom of the fjord. Principal component analysis shows that variations in particle size spectra are independent from one layer to another. Water masses with identical physical and particulate properties located in both sides of the sill illustrate the influence of the St. Lawrence estuary on the Saguenay fjord. These water masses, generally located below the sill depth, indicate the existence of powerful advective mechanisms in this region.

Utility of Meristic and Morphometric Characters for Identification of Capelin (Mallotus villosus) Stocks in Canadian Atlantic Waters

1978 ◽  
Vol 35 (1) ◽  
pp. 124-130 ◽  
Author(s):  
Joan C. Sharp ◽  
Kenneth W. Able ◽  
William C. Leggett ◽  
James E. Carscadden
Keyword(s):  
Mallotus Villosus ◽  
Meristic Characters ◽  
Body Depth ◽  
Morphometric Characters ◽  
Lawrence Estuary ◽  
Grand Banks ◽  
Capelin Mallotus Villosus ◽  
Statistical Separation ◽  
And Migration ◽  
St Lawrence Estuary

Multivariate discriminant function analyses were performed on 9 morphometric and 11 meristic characters of capelin (Mallotus villosus) samples at Île aux Coudres in the St. Lawrence estuary; Sept Îles, Natashquan, and Grande Rivière in the Gulf of St. Lawrence; Southeast Shoal on the Grand Banks; and Herring Neck, Notre Dame Bay, Newfoundland. Analyses of meristic characters provided no evidence of discrete stocks. Analyses of morphometric characters provided strong statistical separation between areas. A posteriori classification of groups yielded 93.1% correct classification for males and 73.3% for females. Only snout length, eye diameter, head length, and body depth contributed significantly to the separation obtained. These findings suggest that meristic characters offer little potential for stock identification in Canadian Atlantic waters. Morphometric characters may prove useful, but further study, corroborated with life history and migration data, is required to confirm this. Key words: capelin, Mallotus villosus, meristics, morphometrics, stock separation, Gulf of St. Lawrence, Newfoundland, Canadian Atlantic, multivariate analysis

Cardiorespiratory fitness is positively associated with both healthy and western dietary pattern in Iranian middle-aged

2020 ◽  
pp. 1-10
Author(s):  
Hossein Shahinfar ◽  
Farhang Djafari ◽  
Nadia Babaei ◽  
Samira Davarzani ◽  
Mojdeh Ebaditabar ◽  
...  
Keyword(s):  
Cardiorespiratory Fitness ◽  
Dietary Patterns ◽  
Dietary Pattern ◽  
Principal Component ◽  
Total Sample ◽  
Linear Regression Models ◽  
Middle Aged ◽  
Anthropometric Measures ◽  
Western Dietary Pattern ◽  
Healthy Dietary Pattern

Abstract. Background: The association between dietary patterns and cardiorespiratory fitness (CRF) is not well established. Objective: We sought to investigate association between a posteriori dietary pattern and CRF in middle-aged adults. Design: Adults (n = 276), aged 20–74 years, who were residents of Tehran, Iran were recruited. Diet was assessed by using a validated 168-item semi-quantitative food frequency questionnaire. Principal component analysis was used to derive dietary patterns. Socio-economic status, anthropometric measures, body composition, and blood pressure were recorded. CRF was assessed by using a graded exercise treadmill test. Analysis of variance and linear regression models were used to discern the association between dietary patterns and CRF. Results: Higher scores of the healthy dietary pattern had no association with VO2max (p = 0.13 ). After controlling for potential confounders, VO2max was positively associated across tertiles of healthy dietary patterns (p < 0.001). Higher adherence to the “mixed” dietary pattern was inversely related to VO2max (p < 0.01). After adjusting for confounders, the significant association disappeared (p = 0.14). Higher scores of the “Western” dietary pattern was not associated with VO2max (p = 0.06). However, after controlling for potential confounders, VO2max was positively associated with the “Western” dietary pattern (p = 0.01). A positive linear association between the “healthy” dietary pattern and CRF for the total sample (R2 = 0.02; p < 0.01) were presented. Conclusions: Overall, our findings suggest that higher adherence to a “healthy” and “Western” dietary pattern was positively associated with CRF. However, further studies are required to examine and clarify the causal relationship between dietary patterns and CRF.

Carotid endarterectomy in patients with foetal-type posterior circle of Willis: Is there an indication for local anaesthesia?

VASA ◽  
2011 ◽  
Vol 40 (5) ◽  
pp. 404-407
Author(s):  
Maras ◽  
Tzormpatzoglou ◽  
Papas ◽  
Papanas ◽  
Kotsikoris ◽  
...  
Keyword(s):  
Carotid Endarterectomy ◽  
Local Anaesthesia ◽  
Anatomical Variation ◽  
Anatomical Variations ◽  
Circle Of Willis ◽  
Variable Degree ◽  
Operative Complications ◽  
The Right ◽  
Ica Stenosis ◽  
Symptomatic Stenosis

Foetal-type posterior circle of Willis is a common anatomical variation with a variable degree of vessel asymmetry. In patients with this abnormality, carotid endarterectomy (CEA) may create cerebral hypo-perfusion intraoperatively, and this may be underestimated under general anaesthesia. There is currently no evidence that anatomical variations in the circle of Willis represent an independent risk factor for stroke. Moreover, there is a paucity of data on treating patients with such anatomical variations and co-existing ICA stenosis. We present a case of CEA under local anaesthesia (LA) in a 52-year-old female patient with symptomatic stenosis of the right ICA and coexistent foetal-type posterior circle of Willis. There were no post-operative complications and she was discharged free from symptoms. She was seen again 3 months later and was free from complications. This case higlights that LA should be strongly considered to enable better intra-operative neurological monitoring in the event of foetal-type posterior circle of Willis.

scholarly journals Benthic fluxes of dissolved organic nitrogen in the lower St. Lawrence estuary and implications for selective organic matter degradation

2013 ◽  
Vol 10 (11) ◽  
pp. 7609-7622 ◽  
Author(s):  
M. Alkhatib ◽  
P. A. del Giorgio ◽  
Y. Gelinas ◽  
M. F. Lehmann
Keyword(s):  
Organic Matter ◽  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Bottom Water ◽  
Estuarine Sediments ◽  
Internal Source ◽  
Lawrence Estuary ◽  
Element Partitioning ◽  
Sediment Porewaters ◽  
St Lawrence Estuary

Abstract. The distribution of dissolved organic nitrogen (DON) and carbon (DOC) in sediment porewaters was determined at nine locations along the St. Lawrence estuary and in the gulf of St. Lawrence. In a previous manuscript (Alkhatib et al., 2012a), we have shown that this study area is characterized by gradients in the sedimentary particulate organic matter (POM) reactivity, bottom water oxygen concentrations, and benthic respiration rates. Based on the porewater profiles, we estimated the benthic diffusive fluxes of DON and DOC in the same area. Our results show that DON fluxed out of the sediments at significant rates (110 to 430 μmol m−2 d−1). DON fluxes were positively correlated with sedimentary POM reactivity and varied inversely with sediment oxygen exposure time (OET), suggesting direct links between POM quality, aerobic remineralization and the release of DON to the water column. DON fluxes were on the order of 30 to 64% of the total benthic inorganic fixed N loss due to denitrification, and often exceeded the diffusive nitrate fluxes into the sediments. Hence they represented a large fraction of the total benthic N exchange, a result that is particularly important in light of the fact that DON fluxes are usually not accounted for in estuarine and coastal zone nutrient budgets. In contrast to DON, DOC fluxes out of the sediments did not show any significant spatial variation along the Laurentian Channel (LC) between the estuary and the gulf (2100 ± 100 μmol m−2 d−1). The molar C / N ratio of dissolved organic matter (DOM) in porewater and the overlying bottom water varied significantly along the transect, with lowest C / N in the lower estuary (5–6) and highest C / N (> 10) in the gulf. Large differences between the C / N ratios of porewater DOM and POM are mainly attributed to a combination of selective POM hydrolysis and elemental fractionation during subsequent DOM mineralization, but selective adsorption of DOM to mineral phases could not be excluded as a potential C / N fractionating process. The extent of this C- versus N- element partitioning seems to be linked to POM reactivity and redox conditions in the sediment porewaters. Our results thus highlight the variable effects selective organic matter (OM) preservation can have on bulk sedimentary C / N ratios, decoupling the primary source C / N signatures from those in sedimentary paleoenvironmental archives. Our study further underscores that the role of estuarine sediments as efficient sinks of bioavailable nitrogen is strongly influenced by the release of DON during early diagenetic reactions, and that DON fluxes from continental margin sediments represent an important internal source of N to the ocean.

Pre-exposure to Cu2+ and CuO NPs leads to infection of caged blue mussels, Mytilus edulis L., by pathogenic microalga: Pilot study in the Lower St. Lawrence Estuary (Québec, Canada)

2021 ◽  
Vol 166 ◽  
pp. 112180
Author(s):  
Michael Zuykov ◽  
Galina Kolyuchkina ◽  
Graeme Spiers ◽  
Michel Gosselin ◽  
Philippe Archambault ◽  
...  
Keyword(s):  
Pilot Study ◽  
Mytilus Edulis ◽  
Lawrence Estuary ◽  
Blue Mussels ◽  
Cuo Nps ◽  
St Lawrence Estuary

Movement of sturgeons ( Acipenser oxyrinchus oxyrinchus and A. fulvescens ) in the St. Lawrence Estuary: A 35‐year tagging study

2021 ◽  
Author(s):  
Yves Paradis ◽  
Marc Pépino ◽  
Simon Bernatchez ◽  
Denis Fournier ◽  
Léon L’Italien ◽  
...  
Keyword(s):  
Lawrence Estuary ◽  
St Lawrence Estuary ◽  
Acipenser Oxyrinchus

Refinement and Psychometric Properties of the Self-Efficacy for Sleep Hygiene Inventory

2020 ◽  
pp. 019394592094097
Author(s):  
Christine S. Gipson ◽  
Jenifer M. Chilton ◽  
Eric Stocks
Keyword(s):  
Young Adults ◽  
Focus Groups ◽  
Self Efficacy ◽  
Psychometric Testing ◽  
Principal Component ◽  
Sleep Hygiene ◽  
Total Sample ◽  
The Self ◽  
Reliable Measure ◽  
Electronic Survey

The purpose of this study was to determine key concepts of self-efficacy for sleep hygiene among young adults/college students and sleep experts, and to refine the Self-Efficacy for Sleep Hygiene Inventory. The Self-Efficacy for Sleep Hygiene Inventory was revised using input from young adult focus groups and experts. Information from focus groups informed instrument revision. The revised instrument was distributed using an electronic survey to young adults age 18–26 years for a total sample of 296. A principal component analysis with Varimax Orthogonal Rotation was conducted resulting in a three-factor solution. Cronbach’s alphas were: .85 for Behaviors to Adopt (nine items), .79 for Manage Mindset and Environment (eight items), .70 for Behaviors to Avoid (eight items), and .88 for the inventory (twenty-five items). Initial psychometric testing of the Self-Efficacy for Sleep Hygiene Inventory-Revised indicates that it is a reliable measure of self-efficacy for sleep hygiene in young adults age 18–26 years.

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