Results 281 to 290 of about 7,003,083 (346)

Reproductive Effort and Reproductive Values in Periodic Environments

The American Naturalist, 2000
Life-history theory concerns the optimal spread of reproduction over an organism's life span. In variable environments, there may be extrinsic differences between breeding periods within an organism's life, affecting both offspring and parent and giving rise to intergenerational trade-offs.
Jon, Brommer, Hanna, Kokko, Hannu, Pietiäinen   +2 more
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Periodicity in Chthamalus fissus reproduction does not guarantee periodicity in settlement

Marine Ecology Progress Series, 2023
The timing of life history events can have profound implications for populations and communities, especially those events that influence species dispersal and recruitment. In benthic invertebrates, the majority of dispersal occurs during the larval phase of life.
JB Weinstock, N Reyns, M Swiderski, D Flerchinger, J Pineda   +4 more
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Modulated Reproductive Periodicity in Chelonia

Ecology, 1970
After 15 yr tagging at the nesting ground of Chelonia mydas at Tortuguero, Costa Rica, 447 remigration returns have been recorded. These confirm previous indications that some Tortuguero females return to nest every 2 yr and some every 3 yr, with the latter being the more frequent cycle.
Archie Carr, Marjorie H. Carr
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Reproductive Function and Contraception in the Postpartum Period

Obstetrical & Gynecological Survey, 1994
The postpartum period is a time of major cellular and hormonal change enabling the return of pelvic organs and the hypothalamic-pituitary-ovarian axis to the nonpregnant state. Breast-feeding modifies this change and maintains the endocrine profile and uterine endometrium in a "static" state.
I Y, Wang, I S, Fraser
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Basic Reproduction Ratios for Time-Periodic Homogeneous Evolution Systems

SIAM Journal on Applied Mathematics, 2023
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Feng-Bin Wang, Lei Zhang, Xiao-Qiang Zhao   +2 more
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Lunar Periodicity in Reproduction

Nature, 1933
IN view of the recent correspondence in NATURE1 bearing on the question of reproductive periodicity in organisms, I should like to direct attention to some observations made by Miss S. M. Marshall and myself in Australia in 1928–29, which appear to indicate a type of such periodicity not previously recorded. In shallow pools on the Low Isles coral reef,
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Diurnal periodicity in Daphnia reproduction

Hydrobiologia, 1992
The diurnal periodicity of reproduction in a reservoir population of Daphnia galeata Sars was tested by two methods (egg age distribution analyses and direct observation of hatching). No significant diurnal synchronization of reproduction in the natural cladoceran population was found.
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Vaginal oestrus during the reproductive and non-reproductive period in European ground squirrels

Animal Reproduction Science, 2009
Most hibernating animals are thought to be monoestrous because reproductive activity is subject to strong time constraints. In previous studies, female European ground squirrels (Spermophilus citellus) turned out to have elevated oestradiol levels during late lactation and after weaning, indicating ovarian activity during summer.
Anna, Strauss, Ilse E, Hoffmann, Manfred, Walzl, Eva, Millesi   +3 more
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Accelerated reproduction of 2-D periodic waves

Ocean Dynamics, 2021
The paper describes the attempt to develop the accelerated method of simulation of 2-D surface waves with a use of 2-D model derived by simplifications of 3-D equations for potential periodic deep-water waves. The derivation is based on separation of velocity potential in surface-fitted coordinates into linear and non-linear components and analysis of ...
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DIAGNOSTIC IRRADIATION OF WOMEN DURING THE REPRODUCTIVE PERIOD

Obstetrical & Gynecological Survey, 1978
The date of onset of the last menstrual period should be given on radiographic requisitions for all women of reproductive age. Every effort should be made to avoid unnecessary irradiation of any woman who might be pregnant. Radiation damage in the first 2 weeks of pregnancy, however, should be "all or none", resulting in either a miscarriage or a ...
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