Some Factors Influencing Observed Sex Ratios in a Population of Evening Grosbeaks

Bird-Banding ◽  
1976 ◽  
Vol 47 (4) ◽  
pp. 340 ◽  
Author(s):  
Martha Hatch Balph ◽  
David F. Balph
Keyword(s):  
Sex Ratios ◽  
Factors Influencing

Factors Influencing Realized Sex Ratios in Fig Wasps: Double Oviposition and Larval Mortalities

2011 ◽  
Vol 25 (3) ◽  
pp. 254-263 ◽  
Author(s):  
Salah Ghana ◽  
Nazia Suleman ◽  
Stephen G. Compton
Keyword(s):  
Sex Ratios ◽  
Fig Wasps ◽  
Factors Influencing

scholarly journals Understanding factors influencing adverse sex ratios at birth in Bangladesh

2015 ◽  
Author(s):  
Md. Talukder ◽  
Ubaidur Rob ◽  
Md. Hossain ◽  
Forhana Noor
Keyword(s):  
Sex Ratios ◽  
Factors Influencing

Biased sex ratio and niche restriction in Baruscapillaria obsignata (Madsen 1945) (Nematoda, Capillariidae) from Columba livia (Aves, Columbidae)

2011 ◽  
Vol 86 (4) ◽  
pp. 401-405 ◽  
Author(s):  
S. D'Ávila ◽  
E.C.A. Bessa ◽  
S. Souza-Lima ◽  
M.L.A. Rodrigues
Keyword(s):  
Sex Ratio ◽  
Negative Binomial ◽  
Sex Ratios ◽  
Columba Livia ◽  
Nematode Species ◽  
Intensity Of Infection ◽  
Factors Influencing ◽  
Biased Sex Ratio ◽  
The Mean ◽  
Male Sex

AbstractIn the present study populations of the avian nematode species Baruscapillaria obsignata are described from Columba livia. Male and female individuals were obtained from 27 birds, fixed in alcohol/formalin/acetic acid (AFA) and preserved in 70% ethanol. Nematodes were identified and then counted under a stereoscopic microscope. Baruscapillaria obsignata were much more frequent in the anterior third of the small intestine, and females were more abundant than males in all infra populations. The prevalence was 55.6%, mean intensity was 11.8 (median 11.0; range 1–31) and abundance 6.56. In the present study, we observed an aggregated distribution of parasite infrapopulations, as demonstrated by the value of the exponent of the negative binomial distribution, K = 0.2773; by the discrepancy index, D = 0.656 and by the variance/mean ratio, 12.44. The female/male sex ratios found in all infrapopulations were always greater than 1, showing a bias in favour of female abundance. This tendency was especially marked in infrapopulations containing fewer individuals. The sizes of infrapopulations ranged from 5 to 31 individuals. The mean sex ratio observed was 2.69 ± 3.28 (median 1.83; range 0–11). In infrapopulations with 5–15 individuals, the sex ratios observed varied from 2.6 to 11, while in those with 17–31 individuals, the sex ratios were lower, ranging from 1.7 to 2.4. There was a negative correlation between the intensity of infection and the sex ratio of infrapopulations. Results are discussed in terms of possible factors influencing the processes that lead to niche restriction and biased sex ratios in parasite infrapopulations.

Factors influencing brood sex ratios in polyembryonic Hymenoptera

Oecologia ◽  
1993 ◽  
Vol 93 (3) ◽  
pp. 343-348 ◽  
Author(s):  
Ian C. W. Hardy ◽  
Paul J. Ode ◽  
Michael R. Strand
Keyword(s):  
Sex Ratios ◽  
Factors Influencing

Factors Influencing Sex Ratios

1970 ◽  
Vol 8 (5P1) ◽  
pp. 643-647 ◽  
Author(s):  
Landrum B. Shettles
Keyword(s):  
Sex Ratios ◽  
Factors Influencing

Factors influencing adhesive bonding at the bone/implant interface

1992 ◽  
Vol 50 (2) ◽  
pp. 1114-1115
Author(s):  
Julie A. Martini ◽  
Robert H. Doremus
Keyword(s):  
Electron Microscopy ◽  
Adhesive Bonding ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Bone Implant ◽  
Factors Influencing ◽  
Lr White ◽  
Transmission Electron ◽  
New Zealand White Rabbits ◽  
Scanning Electron

Tracy and Doremus have demonstrated chemical bonding between bone and hydroxylapatite with transmission electron microscopy. Now researchers ponder how to improve upon this bond in turn improving the life expectancy and biocompatibility of implantable orthopedic devices.This report focuses on a study of the- chemical influences on the interfacial integrity and strength. Pure hydroxylapatite (HAP), magnesium doped HAP, strontium doped HAP, bioglass and medical grade titanium cylinders were implanted into the tibial cortices of New Zealand white rabbits. After 12 weeks, the implants were retrieved for a scanning electron microscopy study coupled with energy dispersive spectroscopy.Following sacrifice and careful retrieval, the samples were dehydrated through a graduated series starting with 50% ethanol and continuing through 60, 70, 80, 90, 95, and 100% ethanol over a period of two days. The samples were embedded in LR White. Again a graduated series was used with solutions of 50, 75 and 100% LR White diluted in ethanol.

Factors Influencing Electrophysiologic Responsivity in Normal Adults

1965 ◽  
Vol 8 (4) ◽  
pp. 323-347
Author(s):  
Robert Goldstein ◽  
Benjamin RosenblÜt
Keyword(s):  
Conditioned Stimulus ◽  
White Light ◽  
Pure Tone ◽  
Alpha Rhythm ◽  
White Women ◽  
White Men ◽  
Inverse Relation ◽  
Factors Influencing ◽  
Electrodermal Responses ◽  
Normal Adults

Electrodermal and electroencephalic responsivity to sound and to light was studied in 96 normal-hearing adults in three separate sessions. The subjects were subdivided into equal groups of white men, white women, colored men, and colored women. A 1 000 cps pure tone was the conditioned stimulus in two sessions and white light was used in a third session. Heat was the unconditioned stimulus in all sessions. Previously, an inverse relation had been found in white men between the prominence of alpha rhythm in the EEG and the ease with which electrodermal responses could be elicited. This relation did not hold true for white women. The main purpose of the present study was to answer the following questions: (1) are the previous findings on white subjects applicable to colored subjects? (2) are subjects who are most (or least) responsive electrophysiologically on one day equally responsive (or unresponsive) on another day? and (3) are subjects who are most (or least) responsive to sound equally responsive (or unresponsive) to light? In general, each question was answered affirmatively. Other factors influencing responsivity were also studied.

Factors Influencing Pressure in the Portal Vein as Studied in the Intact Animal

1950 ◽  
Vol 16 (1) ◽  
pp. 194-210 ◽  
Author(s):  
Frederick W. Hoffbauer ◽  
Jesse L. Bollman ◽  
John L. Grindlay
Keyword(s):  
Portal Vein ◽  
Intact Animal ◽  
Factors Influencing
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