VARIATION IN ANAL FIN RAY COUNT OF THE REDSIDE SHINER RICHARDSONIUS BALTEATUS (RICHARDSON)

1953 ◽  
Vol 31 (3) ◽  
pp. 211-225 ◽  
Author(s):  
C. C. Lindsey

Anal fin rays were counted on 4766 specimens of Richardsonius balteatus from 61 localities in British Columbia. Individual counts varied from 10 to 21, and mean counts of different populations varied from 12.06 to 17.51. Significant differences in counts occurred between different bodies of water, between recently introduced populations and their parent stock, between different parts of the same lake, and between different year classes. Ray counts tended to be higher amongst females in populations with high over-all means, and higher amongst males in populations with low over-all means. A positive correlation was demonstrated between water temperatures recorded in the vicinity of developing fry and the mean numbers of anal rays produced. Within each latitudinal zone a similar correlation occurred between mean ray count and average air temperature during the spawning season, but data on 109 means of populations in U.S.A. and Canada indicated a tendency, probably genetic, towards production, at equivalent temperature, of higher ray count towards the northern end of the range. Loose correlations between anal ray count and certain other morphological characteristics suggest that these may be dependent on more or less common environmental factors but are not linked by direct causality.

2019 ◽  
Vol 5 (1) ◽  
pp. 113-121 ◽  
Author(s):  
S.M. Talebi ◽  
P. Yadegari ◽  
S. Behzadpour ◽  
A. V. Matsyura

Salvia limbata is an aromatic herb of Lamiaceae, which distributed in different parts of Iran. Studies have revealed that this species has several benefit compounds for human health. In this study, we investigated infra‒specific morphological difference in this species. In total, 21 inflorescence morphological features were evaluated in eight populations; ten individuals were evaluated per each population. Data were analysed using SPSS and MVSP softwares. Morphological traits highly differed among the studied populations and ANOVA test revealed significant differences among most of them. According to UPGMA tree, PCA and PCO plots of morphological characteristics, we reported four distinct phenotypes among the studied populations. CA. Joined plot revealed each of these group were characterized by special traits, which were useful in identification of them. Two phenotypes were monotypic, while the rest were composed of two to four populations. This species has a relative large geographical distribution, the distribution of its populations in diverse area will prevent the focus of natural selection in a given direct. Therefore different phenotypes were found in its different populations.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yevhen Maltsev ◽  
Svetlana Maltseva ◽  
John Patrick Kociolek ◽  
Regine Jahn ◽  
Maxim Kulikovskiy

AbstractUntil now, the reported diversity of representatives from the genus Hantzschia inhabiting soils from different parts of Eurasia was limited to the few species H. amphioxys, H. elongata and H. vivax and some of their infraspecific taxa. We have studied the morphology, ultrastructure and phylogeny of 25 soil diatom strains, which according to published description would be assigned to “H. amphioxys sensu lato” using 18S rDNA, 28S rDNA and rbcL. We show that strains are made up of seven different species of Hantzschia, including five new for science. Five strains were identified as H. abundans. This species has a slight curvature of the raphe near its external proximal ends. Four of the examined strains were represented by different populations of H. amphioxys and their morphological characteristics fully correspond with its isolectotype and epitype. The main specific features of this species include 21–25 striae in 10 μm, 6–11 fibulae in 10 μm, 40–50 areolae in 10 μm and internal proximal raphe endings bent in opposite directions. H. attractiva sp. nov., H. belgica sp. nov., H. parva sp. nov., H. pseudomongolica sp. nov. and H. stepposa sp. nov. were described based on differences in the shape of the valves, significant differences in dimensions, a lower number of striae and areolae in 10 μm and the degree and direction of deflection of the internal central raphe endings. Based on the study of the morphological variability and phylogeny of soil Hantzschia-species from different geographical locations we conclude that while some species such as H. amphioxys are truly cosmopolitan in their distributions, some sympatric populations of pseudocryptic taxa exist in the Holarctic.


2014 ◽  
Vol 66 (1) ◽  
pp. 227-232 ◽  
Author(s):  
J. Jovanovic ◽  
D. Jeremic ◽  
B. Jovanovic ◽  
Maja Vulovic ◽  
P. Sazdanovic ◽  
...  

The aim of this study was to determine the nasal parameters in the population of central Serbia and to compare them with those determined in earlier studies in different populations. The research was conducted on 496 randomly selected persons (262 males and 234 females), aged 18-65 years. The measured parameters were nasal height and nasal breadth and the standard spreading caliper with scale was used for measurements. There were significant differences in the nasal parameters between male and female subjects. The nasal breadth was 34.72 mm in females, and in the male population it was 36.7 mm. The mean values of nasal height were 52.6 mm and 54.32 mm in females and males, respectively. The nasal index in females and males was 66.01 and 67.56, respectively, and the mean value of the nasal index of all respondents was 66.78. After conducting the research it was concluded that the dominant nasal type in the population of the central part of Serbia is leptorrhine. The present study showed the existence of sexual dimorphism in nasal morphology. The data obtained in our study may be useful in anthropological and forensic research, as well as in cosmetic planning and reconstructive surgery.


2004 ◽  
Vol 36 (6) ◽  
pp. 735-740 ◽  
Author(s):  
HELLE PULLMANN ◽  
JÜRI ALLIK ◽  
RICHARD LYNN

The Standard Progressive Matrices test was standardized in Estonia on a representative sample of 4874 schoolchildren aged from 7 to 19 years. When the IQ of Estonian children was expressed in relation to British and Icelandic norms, both demonstrated a similar sigmoid relationship. The youngest Estonian group scored higher than the British and Icelandic norms: after first grade, the score fell below 100 and remained lower until age 12, and after that age it increased above the mean level of these two comparison countries. The difference between the junior school children and the secondary school children may be due to schooling, sampling error or different trajectories of intellectual maturation in different populations. Systematic differences in the growth pattern suggest that the development of intellectual capacities proceeds at different rates and the maturation process can take longer in some populations than in others.


1963 ◽  
Vol 4 (2) ◽  
pp. 193-220 ◽  
Author(s):  
R. J. Berry

It has been suggested (Berry & Searle, 1963) that the discontinuous (‘quasi-continuous’) variants studied by Grüneberg et al. in the skeleton of rodents can be regarded as constituting epigenetic polymorphism in different populations. Comparisons have been made between the incidences of skeletal variants in house mouse populations collected from: corn ricks on a single farm in Hampshire; eleven separated localities in different parts of the British Isles; and nine other places throughout the world. These showed that the method could profitably be used for genetically characterizing and hence comparing populations. There was evidence suggestive of genetical drift between local populations and stabilizing selection over a larger area.


1847 ◽  
Vol 137 ◽  
pp. 217-229 ◽  

In the Fourteenth Volume of the Transactions of the Royal Astronomical Society will be found a full account of the Cavendish apparatus, and of the mode of experimenting followed by Mr. Baily. It will therefore not be necessary for me, in this place, to enter into any detail as to the different parts of the instrument, and the various precautions adopted in order to avoid that singular source of error 'currents of air in the torsion box arising from unequal temperature,’ which had been discovered by Cavendish. It will be sufficient for me to state that all the arrangements are of a highly satisfactory kind, and that I am of opinion that no aerial currents could have existed in the torsion box. The deduction of the mean density of the earth from the observed vibrations of the balls influenced by the torsion force and the attraction of the masses, is founded on a mathematical theory of the motion of the balls given by the Astronomer Royal, Mr. Airy ; and as this theory is certainly insufficient to account for the discrepancies, it will here be necessary to give a brief sketch of it.


2020 ◽  
Vol 8 (4) ◽  
pp. 1845-1848
Author(s):  
HP Sankhyan ◽  
Sanjeev Thakur ◽  
Sunil Kumar ◽  
Karishma . ◽  
Prachi . ◽  
...  

2019 ◽  
Vol 16 (32) ◽  
pp. 263-278
Author(s):  
Vanessa Machado Babinski RAMOS ◽  
Maurício Gammertt RÖHNELT ◽  
Rodrigo BRAMBILLA

This paper reports the main results concerning the synthesis and characterization of methylsilane and octylsilane-modified silicas. The modification of the silicas with these groups aims to make the silica surface hydrophobic and thus compatible with high-density polyethylene (HDPE) in HDPE/silica composites. In the present work, two types of silica were organofunctionalized: a pyrogenic silica and a silica gel. The silicas were characterized by a series of complementary techniques with the objective of investigating the nature of the surface species and their textural and morphological characteristics. The SEM images showed that the modification of the silicas with organosilanes has been not resulted in changes on the morphology and on the size of silica particles. In relation to the texture properties, determined by N2 adsorption-desorption porosimetry, the silica modification resulted in a decrease of the specific area (SBET) and the mean pore volume, a behavior attributed to the partial coverage of the adsorption sites by the organosilane molecules. The TGA analysis showed that both the methylsilane groups and the octylsilane groups on the surface of silica and silica gel are thermally stable up to 200 ° C, which enables the organofunctionalized silicas in terms of thermal stability, for the process of preparing the composites by extrusion. The results of applying these organofunctionalized silicas in the development of HDPE/silica composites will be presented in a subsequent article, part II of this research.


2013 ◽  
Vol 13 (4) ◽  
pp. 356-362 ◽  
Author(s):  
Francisco Elias Ribeiro ◽  
Luc Baudouin ◽  
Patricia Lebrun ◽  
Lázaro José Chaves ◽  
Claudio Brondani ◽  
...  

The tall coconut palm was introduced in Brazil in 1553, originating from the island of Cape Verde. The aim of the present study was to evaluate the genetic diversity of ten populations of Brazilian tall coconut by 13 microsatellite markers. Samples were collected from 195 individuals of 10 different populations. A total of 68 alleles were detected, with an average of 5.23 alleles per locus. The mean expected and observed heterozygosity value was 0.459 and 0.443, respectively. The number of alleles per population ranged from 36 to 48, with a mean of 40.9 alleles. We observed the formation of two groups, the first formed by the populations of Baía Formosa, Georgino Avelino and São José do Mipibu, and the second by the populations of Japoatã, Pacatuba and Praia do Forte. These results reveal a high level of genetic diversity in the Brazilian populations.


2021 ◽  
Author(s):  
Qina He ◽  
Guidong Yao ◽  
Jiahuan He ◽  
Guang Yang ◽  
Ziwen Xu ◽  
...  

Abstract At present, embryo morphology assessment based on the observation of the embryonic morphological characteristics at several specific time points has been mainly used for selecting the high-quality embryo. However, we all know that embryo development is a dynamic process. Many research results on the correlation between the embryo morphokinetic parameters and embryo quality and development potential were inconsistent. With the help of time-lapse imaging, the development processes and outcomes of a total of 365 embryos were cultured and analyzed in this study. The results showed that the mean tPNf and t2 of the high-quality embryo were significantly shorter than the low-quality embryo; the mean t2PBe and tPNa of the high-quality embryo from the implantation group were significantly shorter than those from the non-implantation group. In addition, based on the quartile grouping of each morphokinetic parameter, the embryos that had 21.15≤tPNf≤25.30 value were significantly higher in embryo quality when compared with the embryos that had the tPNf values outside the range on Days 3. Similarly, the embryos that had values of t2≤25.60 were significantly higher in embryo quality than those with outside the range values on Days 3. Thus, we demonstrated that the morphokinetic parameter evaluated using a time-lapse embryo monitoring system can predict the embryo quality, and be benefit for the selection of the high-quality embryos and improvement for the implantation success of the patient in assisted reproductive technologies.


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