Intertidal zonation and seasonality of the marine hydroid Dynamena pumila (Cnidaria: Hydrozoa)

2002 ◽  
Vol 80 (9) ◽  
pp. 1526-1536
Author(s):  
Lea-Anne Henry
Keyword(s):  
Environmental Conditions ◽  
Temporal Dynamics ◽  
Wave Exposure ◽  
Tidal Range ◽  
Bay Of Fundy ◽  
Rocky Shores ◽  
Four Seasons ◽  
The Mean ◽  
Highly Correlated ◽  
Number Of Branches

The vertical zonation and temporal dynamics of the marine hydroid Dynamena pumila were assessed across a wave-exposure gradient on five rocky shores in the Bay of Fundy, Atlantic Canada. Hydroid abundance and occupancy (i.e., percentage occurrence in a quadrat) were measured in 0.25-m2 quadrats at eight vertical elevations for each site over four consecutive seasons. Hydroid abundance and occupancy were highly correlated (R2 = 0.877). Estimates of hydroid fertility (percentage of sexually reproductive colonies) and size (stem height and number of branches) were obtained in five quadrats at every elevation over the four seasons. Abundance peaked at about 37.5–62.5% of the mean tidal range, with maximum abundance at the site with moderate wave exposure. Abundance peaked during the summer and dropped dramatically over the winter, particularly at the more wave-exposed sites. Winter ice scour and unfavourable environmental conditions reduced hydroid abundance, fertility, and size during the winter. This study demonstrates dramatic shifts in the distribution, fertility, and size of a marine hydroid. The importance of wave action, ice scour, and seasonal changes in environmental conditions is highlighted to emphasize their roles in regulating intertidal hydroid communities on boreal rocky shores.

Energy Considerations in the Bay of Fundy System

1958 ◽  
Vol 15 (2) ◽  
pp. 115-134 ◽  
Author(s):  
H. J. McLellan
Keyword(s):  
Mixed State ◽  
Roughness Length ◽  
Tidal Range ◽  
Bay Of Fundy ◽  
The Moon ◽  
Tidal Friction ◽  
Roughness Elements ◽  
Passamaquoddy Bay ◽  
The Mean ◽  
Average Size

Following developments of Taylor, Allard and Redfield, the rates at which energy is dissipated in the Bay of Fundy in various ways are calculated. A total of 30.9 × 106 kw. is transmitted into the bay of which 1.26 × 106 kw. is transmitted into Passamaquoddy Bay. Work is done on the moon at the rate of 2.48 × 106 kw. and 0.03 × 106 kw. is used to maintain the mixed state in the waters of the Bay of Fundy. The remaining 27.1 × 106 kw. must be dissipated by tidal friction. This value is compatible with the usual concepts of turbulent flow over a rough surface if the "roughness length" (Z0) is equal to 0.4 cm. or the average size of the roughness elements (E) is about 11 cm.The effect which the extraction of additional power from the system would have on tidal ranges is evaluated. The range at the head of the Bay of Fundy would decrease at the rate of 0.84 foot (26 cm.) for each million kilowatts. The proposed Passamaquoddy Project would probably increase the mean tidal range at Hopewell Cape by 0.6 foot (18 cm.)

scholarly journals Desenvolvimento de um microerosómetro do tipo TMEM para aplicação em plataformas rochosas litorais

Finisterra ◽  
2012 ◽  
Vol 36 (71) ◽  
Author(s):  
Mário Neves ◽  
Ana Ramos Pereira ◽  
Manuela Laranjeira ◽  
Jorge Trindade
Keyword(s):  
Environmental Conditions ◽  
Tidal Range ◽  
Rock Surface ◽  
Western Coast ◽  
Data Set ◽  
Shore Platform ◽  
Erosion Rates ◽  
The Mean ◽  
Shore Platforms ◽  
Experimental Survey

DEVELOPMENT AND APPLICATION OF A TRAVERSING MICRO-EROSION METER FOR SHORE PLATFORMS – The study of the shore platforms specific environmental conditions requires accurate equipment to measure erosion rates. In this paper, the construction details of a Traversing Micro-Erosion Meter (TMEM) is described. This TMEM adds some improvements to previous devices that aim to increase the data set collected, both in quality and in quantity. The installation and measurement procedures are described, as well as the advantages and limitations of this equipment. An experimental survey was carried out within the tidal range of the limestone shore platform of Tombadoiros, in a sector of the Portuguese western coast. For a 96 days period in the autumn/winter of 2000/2001, the mean rate of erosion at the site was 0,153mm/year. However, this result includes disturbances associated with the settlement of the black lichen Verrucaria maura in 58 % of the measuring points. It was found that the mean rate of erosion in the clean rock surface was 2,5 higher when compared to the area colonized by the lichen.

Detection of Circulating Tissue Factor and Factor VII in a Normal Population

1996 ◽  
Vol 75 (05) ◽  
pp. 772-777 ◽  
Author(s):  
Sybille Albrecht ◽  
Matthias Kotzsch ◽  
Gabriele Siegert ◽  
Thomas Luther ◽  
Heinz Großmann ◽  
...  
Keyword(s):  
Tissue Factor ◽  
Normal Population ◽  
Mean Value ◽  
Factor Vii ◽  
Significant Difference ◽  
Age Dependent ◽  
The Mean ◽  
Highly Correlated ◽  
And Gender

SummaryThe plasma tissue factor (TF) concentration was correlated to factor VII concentration (FVIIag) and factor VII activity (FVIIc) in 498 healthy volunteers ranging in age from 17 to 64 years. Immunoassays using monoclonal antibodies (mAbs) were developed for the determination of TF and FVIIag in plasma. The mAbs and the test systems were characterized. The mean value of the TF concentration was 172 ± 135 pg/ml. TF showed no age- and gender-related differences. For the total population, FVIIc, determined by a clotting test, was 110 ± 15% and the factor VIlag was 0.77 ± 0.19 μg/ml. FVII activity was significantly increased with age, whereas the concentration demonstrated no correlation to age in this population. FVII concentration is highly correlated with the activity as measured by clotting assay using rabbit thromboplastin. The ratio between FVIIc and FVIIag was not age-dependent, but demonstrated a significant difference between men and women. Between TF and FVII we could not detect a correlation.

Examining the Temporal Dynamics of Anxiety and Depressive Symptoms During a Therapist-Supported, Smartphone-Based Intervention for Major Depression (Preprint)

2020 ◽  
Author(s):  
Santiago Allende ◽  
Valerie Forman-Hoffman ◽  
Philippe Goldin
Keyword(s):  
Depressive Symptoms ◽  
Temporal Relationship ◽  
Temporal Dynamics ◽  
Digital Health ◽  
Quadratic Function ◽  
Depression Symptoms ◽  
Symptoms Of Depression ◽  
Effect Model ◽  
End Of Treatment ◽  
Highly Correlated

UNSTRUCTURED Background: Anxiety and depression symptoms are highly correlated in adults with depression; however, little is known about their interaction and temporal dynamics of change during treatment. Thus, the primary aim of this study was to examine the temporal dynamics of anxiety and depressive symptoms during a 12-week therapist-supported, smartphone-delivered digital health intervention for symptoms of depression and anxiety, the Meru Health Program (MHP). Method: A total of 290 participants from the MHP were included in the present analyses (age Mean = 39.64, SD = 10.25 years; 79% female; 54% self-reported psychotropic medication use). A variance components model was used to examine whether (1) reporting greater anxiety during the current week relative to anxiety reported in other weeks would be associated with greater reporting of depressive symptoms during the current week, while a time-varying effect model was used to examine whether, (2) consistent with findings reported by Wright et al. (2014), the temporal relationship between anxiety and depressive symptoms during the intervention would be expressed as a quadratic function marked by a weak association at baseline, followed by an increase to a peak before demonstrating a negligible decrease until the end of treatment. Results: In support of hypothesis 1, we found that reporting greater anxiety symptoms during the current week relative to other weeks was associated with greater depressive symptoms during the current week. Contrary to hypothesis 2, the temporal relationship between anxiety and depressive symptoms evidenced a recurring pattern, with the association increasing during the initial weeks, decreasing during mid-treatment and sharply increasing toward the end of treatment. Conclusions: The present findings demonstrate that anxiety and depressive symptoms overlap and fluctuate in concert during a smartphone-based intervention for anxiety and depressive symptoms. The present findings may warrant more refined intervention strategies specifically tailored to co-occurring patterns of change in symptoms.

COLONY OF THE FUNGUS Aspergillus oryzae AND SELF-AFFINE FRACTAL GEOMETRY OF GROWTH FRONTS

Fractals ◽  
1993 ◽  
Vol 01 (01) ◽  
pp. 11-19 ◽  
Author(s):  
SHU MATSUURA ◽  
SASUKE MIYAZIMA
Keyword(s):  
Aspergillus Oryzae ◽  
Environmental Conditions ◽  
Fractal Geometry ◽  
Nutrient Concentration ◽  
Incubation Temperature ◽  
Characteristic Exponent ◽  
Growth Front ◽  
Favorable Condition ◽  
The Self ◽  
The Mean

A variety of colony shapes of the fungus Aspergillus oryzae under varying environmental conditions such as the nutrient concentration, medium stiffness and incubation temperature are obtained, ranging from a homogeneous Eden-like to a ramified DLA-like pattern. The roughness σ(l, h) of the growth front of the band-shaped colony, where h is the mean front height within l of the horizontal range, satisfies the self-affine fractal relation under favorable environmental conditions. In the most favorable condition of our experiments, its characteristic exponent is found to be a little larger than that of the 2-dimensional Eden model.

scholarly journals Scotopic thresholds on dark-adapted chromatic perimetry in healthy aging and age-related macular degeneration

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manjot Kaur Grewal ◽  
Shruti Chandra ◽  
Alan Bird ◽  
Glen Jeffery ◽  
Sobha Sivaprasad
Keyword(s):  
Macular Degeneration ◽  
Healthy Aging ◽  
Intraclass Correlation ◽  
Age Related Macular Degeneration ◽  
Healthy Individuals ◽  
Age Related ◽  
Rod Function ◽  
The Mean ◽  
Highly Correlated ◽  
Effect Of Age

AbstractTo evaluate the effect of aging, intra- and intersession repeatability and regional scotopic sensitivities in healthy and age-related macular degeneration (AMD) eyes. Intra- and intersession agreement and effect of age was measured in healthy individuals. The mean sensitivity (MS) and pointwise retinal sensitivities (PWS) within the central 24° with 505 nm (cyan) and 625 nm (red) stimuli were evaluated in 50 individuals (11 healthy and 39 AMD eyes). The overall intra- and intersession had excellent reliability (intraclass correlation coefficient, ICC > 0.90) and tests were highly correlated (Spearman rs = 0.75–0.86). Eyes with subretinal drusenoid deposit (SDD) had reduced PWS centrally, particularly at inferior and nasal retinal locations compared with controls and intermediate AMD (iAMD) without SDD. There was no difference in MS or PWS at any retinal location between iAMD without SDD and healthy individuals nor between iAMD with SDD and non-foveal atrophic AMD groups. Eyes with SDD have reduced rod function compared to iAMD without SDD and healthy eyes, but similar to eyes with non-foveal atrophy. Our results highlight rod dysfunction is not directly correlated with drusen load and SDD location.

Étude du développement hétéroblastique chez quelques espèces du genre Medicago

1983 ◽  
Vol 61 (8) ◽  
pp. 2212-2223 ◽  
Author(s):  
Catherine Damerval
Keyword(s):  
Environmental Conditions ◽  
Mean Value ◽  
Annual Species ◽  
The Mean ◽  
Shape Changes

Seven foliar types were defined for the first leaf in the heteroblastic development of seven annual species of Medicago L. Among the species, M. aculeata and M. murex have a typical foliar form. There is no relation between the first leaf and the succeeding trifoliolate one. The shape changes of the middle foliole of the trifoliolate leaves during the development allowed to establish a foliar sequence whose mean length was used to suggest an evolutive hierarchy among the taxa. Five quantitative variables were analysed on the first and on the sixth leaf for stability according to environmental conditions; the two stable variables (L/l and L/Pl) have a best discriminant value for the first leaf than for the sixth one. However, intraspecific heterogeneity is high in both cases. A relation between the flowering precocity and the mean value of one of the sixth leaf's variables (that is, the ratio of the length to the width of the foliole limb) was demonstrated in four species only. The heteroblastic development not only allows to establish a relation between foliar stage and physiologic age, but it itself constitutes a very good taxonomic and systematic criterium; it allowed to identify the seven species studied.

Elemental content of mast cell granules measured by X-ray microanalysis of rat thymic tissue sections

1986 ◽  
Vol 83 (1) ◽  
pp. 77-87 ◽  
Author(s):  
M.D. Kendall ◽  
A. Warley
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Elemental Content ◽  
Thymic Tissue ◽  
X Ray ◽  
Tissue Sections ◽  
Freeze Dried ◽  
The Mean ◽  
Highly Correlated ◽  
The Individual

Mast cell granules were examined by fully quantitative X-ray microanalysis of 20 cells in freeze-dried cryosections. The mast cells were situated mainly in the connective tissue of the thymic capsule of five adult male Carworth Sprague Europe rats. In addition 30 red blood cells were analysed from the same sections. Nineteen of the mast cells had granules rich in S and K. One cell had smaller granules, and in this cell the granules contained high [Ca] and [P] instead of high [S] and [K]. In the majority of cells (13) the S:K ratio was highly correlated and less than 2.2, whereas in the remaining six cells the individual granule ratios were very variable in any one cell and much higher. The mean granule [K] (994 +/− 57 mmol kg-1 dry wt) was about four times the mean cytoplasmic level of 227 +/− 81 mmol kg-1 dry wt. The existence of this difference in concentration between the granules and the cytoplasm suggests that the K in the granules must be bound. The relationship between the [K] and [S] is discussed with regard to the possible binding of heparin and amines in the granules.

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