The Population Biology of Gehyra (Gekkonidae, Reptilia) .2. Individual-Movements and Colonization by Gehyra-Variegata and Gehyra-Nana

1987 ◽  
Vol 35 (6) ◽  
pp. 587 ◽  
Author(s):  
C Moritz
Keyword(s):  
Gene Flow ◽  
Population Biology ◽  
The Other ◽  
Site Attachment ◽  
Chromosomal Speciation ◽  
Low Levels ◽  
Habitat Generalist ◽  
Removal Studies ◽  
Gehyra Variegata ◽  
Local Dispersal

Dispersal and colonisation were studied in two species of Gehyra to determine whether they are likely to have the low levels of gene flow that are necessary for some modes of chromosomal speciation. One of the species examined, G. nana, lives only on rocks, whereas the other, G, variegata, is a habitat generalist. A study of marked individuals of both species confirmed an earlier report of strong site attachment by individuals of Gehyra, although some longer distance movements were detected. By contrast, removal studies showed that individuals of both species are capable of rapidly recolonising vacant habitat. Many of the colonisers had moved distances over two to three times those detected for the marked animals. The results suggest that dispersal within populations of Gehyra may not be as restricted as previously thought. Microgeographic recolonisation and local dispersal could cause moderate to high levels of gene flow. If moderate gene flow is a common feature of populations of Gehyra, then speciation via single, severely underdominant chromosome changes is unlikely.

Microsatellites mapping for non-model species with chromosomal rearrangement: a case study in the frog Quasipaa boulengeri (Anura: Dicroglossidae)

Genome ◽  
2017 ◽  
Vol 60 (8) ◽  
pp. 707-711 ◽  
Author(s):  
Xiuyun Yuan ◽  
Siqi Yuan ◽  
Ya Liu ◽  
Yun Xia ◽  
Xiaomao Zeng
Keyword(s):  
Gene Flow ◽  
Chromosomal Rearrangement ◽  
The Other ◽  
Model Species ◽  
Chromosomal Speciation ◽  
Frog Species ◽  
Suppressed Recombination ◽  
Selection Of ◽  
Chromosome Level

Gene mapping is an important resource for understanding the evolution of genes and cytogenetics. Model species with a known genetic map or genome sequence allow for the selection of genetic markers on a desired chromosome, while it is hard to locate these markers on chromosomes of non-model species without such references. A frog species, Quasipaa boulengeri, shows chromosomal rearrangement polymorphisms, making itself a fascinating model for chromosomal speciation mediated by suppressed recombination. However, no markers have been located on its rearranged chromosomes. We present a complete protocol to map microsatellites based on mechanical microdissection and chromosome amplification techniques. Following this protocol, we mapped 71 microsatellites of Q. boulengeri at the chromosome level. In total, eight loci were assigned to rearranged chromosomes, and the other 63 loci might attach to other chromosomes. These microsatellites could be used to compare the gene flow and verify the chromosomal suppressed recombination hypothesis in Q. boulengeri. This integrated protocol could be effectively used to map genes to chromosomes for non-model species.

NEUROTIC SYMPTOMATICS RELATED TO PERSONAL CHARACTERISTICS IN YOUTH

2019 ◽  
pp. 2014-2019
Author(s):  
Milen Dimov
Keyword(s):  
Personal Characteristics ◽  
The Self ◽  
The Other ◽  
Social Responsiveness ◽  
Training Process ◽  
Self Assessment ◽  
School Year ◽  
Real Behavior ◽  
Low Levels ◽  
The Ideal

The present study traces the dynamics of personal characteristics in youth and the manifested neurotic symptoms in the training process. These facts are the reason for the low levels of school results in the context of the existing theoretical statements of the problem and the empirical research conducted among the trained teenagers. We suggest that the indicators of neurotic symptomatology in youth – aggression, anxiety, and neuroticism, are the most demonstrated, compared to the other studied indicators of neurotic symptomatology. Studies have proved that there is a difference in the act of neurotic symptoms when tested in different situations, both in terms of expression and content. At the beginning of the school year, neurotic symptoms, more demonstrated in some aspects of aggressiveness, while at the end of school year, psychotism is more demonstrated. The presented summarized results indicate that at the beginning of the school year, neurotic symptoms are strongly associated with aggression. There is a tendency towards a lower level of social responsiveness, both in the self-assessment of real behavior and in the ideal “I”-image of students in the last year of their studies. The neurotic symptomatology, more demonstrated due to specific conditions in the life of young people and in relation to the characteristics of age.

Sexual Aggressivity and Androgens

1987 ◽  
Vol 151 (3) ◽  
pp. 398-400 ◽  
Author(s):  
J. Raboch ◽  
H. Černá ◽  
P. Zemek
Keyword(s):  
Sexual Activity ◽  
Sex Hormones ◽  
Aggressive Behaviour ◽  
Point Of View ◽  
The Other ◽  
Klinefelter’S Syndrome ◽  
Klinefelter's Syndrome ◽  
Sexually Aggressive ◽  
Male Sex ◽  
Low Levels

Male sex hormones are ascribed a great importance in the literature from the point of view of sexual activity and aggressive behaviour. Two cases of sexually motivated murder are described, committed by delinquents with low levels of testosterone in plasma: one a patient with Klinefelter's syndrome; the other a man after castration. Even a decreased level of androgens, either primary or secondary, is not an absolute prevention of sexually aggressive behaviour.

scholarly journals Hydrometeor and latent heat profiles of tropical cyclones Conson, Ivan and Catarina using PR/TRMM data

2010 ◽  
Vol 25 (2) ◽  
pp. 156-174 ◽  
Author(s):  
Marcelo Barbio Rosa ◽  
Augusto Pereira Filho ◽  
Prakki Satyamurty
Keyword(s):  
Water Content ◽  
Latent Heat ◽  
High Water ◽  
Mean Value ◽  
The Other ◽  
High Water Content ◽  
Hurricane Ivan ◽  
Two Systems ◽  
Low Levels ◽  
Ice Content

ABSTRACT Microphysical and thermodynamical features of two tropical systems, namely Hurricane Ivan and Typhoon Conson, and one sub-tropical, Catarina, have been analyzed based on space-born radar PR measurements available on the TRMM satellite. The procedure to classify the reflectivity profiles followed the Heymsfield et al (2000) and Steiner et al (1995) methodologies. The water and ice content have been calculated using a relationship obtained with data of the surface SPOL radar and PR in Rondonia State in Brazil. The diabatic heating rate due to latent heat release has been estimated using the methodology developed by Tao et al (1990). A more detailed analysis has been performed for Hurricane Catarina, the first of its kind in South Atlantic. High water content mean value has been found in Conson and Ivan at low levels and close to their centers. Results indicate that hurricane Catarina was shallower than the other two systems, with less water and the water was concentrated closer to its center. The mean ice content in Catarina was about 0.05 g kg-1 while in Conson it was 0.06 g kg-1 and in Ivan 0.08 g kg-1. Conson and Ivan had water content up to 0.3 g kg-1 above the 0ºC layer, while Catarina had less than 0.15 g kg-1. The latent heat released by Catarina showed to be very similar to the other two systems, except in the regions closer to the center.

scholarly journals Six new cases confirm the clinical molecular profile of complete combined 17α-hydroxylase/ 17,20-lyase deficiency in Brazil

2010 ◽  
Vol 54 (8) ◽  
pp. 711-716 ◽  
Author(s):  
Daiane Rodrigues Barbosa Belgini ◽  
Maricilda Palandi de Mello ◽  
Maria Tereza Matias Baptista ◽  
Daniel Minutti de Oliveira ◽  
Fernanda Canova Denardi ◽  
...  
Keyword(s):  
Present Report ◽  
Molecular Data ◽  
The Other ◽  
Renin Activity ◽  
Inguinal Region ◽  
Molecular Profile ◽  
Hydroxylase Deficiency ◽  
Lyase Deficiency ◽  
Frequent Mutations ◽  
Low Levels

In 2004, Costa-Santos and cols. reported 24 patients from 19 Brazilian families with 17α-hydroxylase deficiency and showed that p.W406R and p.R362C corresponded to 50% and 32% of CYP17A1 mutant alleles, respectively. The present report describes clinical and molecular data of six patients from three inbred Brazilian families with 17α-hydroxlyse deficiency. All patients had hypogonadism, amenorrhea and hypertension at diagnosis. Two sisters were found to be 46,XY with both gonads palpable in the inguinal region. All patients presented hypergonadotrophic hypogonadism, with high levels of ACTH (> 104 ng/mL), suppressed plasmatic renin activity, low levels of potassium (< 2.8 mEq/L) and elevated progesterone levels (> 4.4 ng/mL). Three of them, including two sisters, were homozygous for p.W406R mutation and the other three (two sisters and one cousin) were homozygous for p.R362C. The finding of p.W406R and p.R362C in the CYP17A1 gene here reported in additional families, confirms them as the most frequent mutations causing complete combined 17α-hydroxylase/17,20-lyase deficiency in Brazilian patients.

Comparison of the productivity of Texel and Rouge de l’Ouest ewes and their crosses

2002 ◽  
Vol 75 (3) ◽  
pp. 459-468 ◽  
Author(s):  
L. E. R. Dawson ◽  
A. F. Carson ◽  
L. O. W. McClinton
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Live Weight ◽  
The Other ◽  
Superior Performance ◽  
Live Weight Gain ◽  
Low Levels ◽  
Lamb Growth ◽  
Average Figure

AbstractAn experiment was undertaken to compare the productivity of crossbred ewes, produced by crossing Texel sires with Rouge de l’Ouest (Rouge) dams and Rouge sires with Texel dams, relative to purebred Texel and Rouge ewes. The purebred and crossbred ewes were crossed with Rouge and Texel sires. The proportion of productive ewes was similar in the purebred and crossbred ewes with an average figure of 0·92. Irrespective of crossing sire, Rouge ewes produced 0·48 more lambs per ewe lambed than Texel ewes (P < 0·001). The two crossbred ewe types (Texel ✕ Rouge and Rouge ✕ Texel) each produced similar numbers of lambs (on average 1·92 lambs per ewe lambed). Individual heterosis values for ewe fertility and prolificacy were small and not significant (–1·67 for the proportion of productive ewes and –3·14 for the number of lambs born per ewe lambed). Maternal heterosis values were also not significant but were of larger magnitude (6·26 for ewe fertility and 3·12 for prolificacy). Lamb mortality (number of lambs born dead per ewe lambed) at birth was similar for purebred Rouge (0·44) and Texel (0·30) ewes and was significantly reduced by crossbred matings and mating the crossbred ewes (individual heterosis –30·68, P < 0·10; maternal heterosis –80·23, P < 0·001). Individual and maternal heterosis values for lamb growth rate from birth to six weeks were 8 (P < 0·05) and 4 (P > 0·05) respectively. Lamb growth rate from birth to weaning was significantly lower in lambs from Texel ewes compared with those from the other genotypes (P < 0·05). Individual and maternal heterosis values for live-weight gain from birth to weaning were 5 (P < 0·10) and 5 (P < 0·01). The results of the current study demonstrate the superior performance of purebred Rouge ewes compared with purebred Texel ewes in terms of prolificacy and lamb growth rate from birth to weaning. However, both breeds had high lamb mortality at birth. Crossbreeding led to the production of hybrid ewes which had relatively high prolificacy with low levels of dystocia and lamb mortality.

scholarly journals RADseq data reveal a lack of admixture in a mouse lemur contact zone contrary to previous microsatellite results

2021 ◽  
Author(s):  
Jelmer Wijtze Poelstra ◽  
B. Karina Montero ◽  
Jan Lüdemann ◽  
Ziheng Yang ◽  
S. Jacques Rakotondranary ◽  
...  
Keyword(s):  
Gene Flow ◽  
Contact Zone ◽  
Mouse Lemur ◽  
Biological Processes ◽  
Microsatellite Data ◽  
Ancestral Gene ◽  
Mouse Lemurs ◽  
Low Levels ◽  
Future Work ◽  
Lemur Species

Despite being one of the most fundamental biological processes, the process of speciation remains poorly understood in many groups of organisms. Mouse lemurs are a species-rich genus of small primates endemic to Madagascar, whose diversity has only recently been uncovered using genetic data and is primarily found among morphologically cryptic, allopatric populations. To assess to what extent described species represent reproductively isolated entities, studies are needed in areas where mouse lemur taxa come into contact. Hybridization has previously been reported in a contact zone between two closely related mouse lemur species (Microcebus murinus and M. griseorufus) based on microsatellite data. Here, we revisit this system using RADseq data for populations in, near, and far from the contact zone, including many of the individuals that had previously been identified as hybrids. Surprisingly, we find no evidence for admixed nuclear ancestry in any of the individuals. Re-analyses of microsatellite data and simulations suggest that previously inferred hybrids were false positives and that the program NewHybrids can be particularly sensitive to erroneously inferring hybrid ancestry. Using coalescent-bases analyses, we also show an overall lack of recent gene flow between the two species, and low levels of ancestral gene flow. Combined with evidence for local syntopic occurrence, these data indicate that M. murinus and M. griseorufus are reproductively isolated. Finally, we estimate that they diverged less than a million years ago, suggesting that completion of speciation is relatively rapid in mouse lemurs. Future work should focus on the underpinnings of reproductive isolation in this cryptic primate radiation, which are mostly unknown. Our study also provides a cautionary tale for the inference of hybridization with microsatellite data.

Population genetic structure in duckweed (Lemna minor, Lemnaceae)

1996 ◽  
Vol 74 (2) ◽  
pp. 222-230 ◽  
Author(s):  
Christopher T. Cole ◽  
Martin I. Voskuil
Keyword(s):  
Gene Flow ◽  
Genetic Structure ◽  
Population Genetic ◽  
Lemna Minor ◽  
Vegetative Reproduction ◽  
Low Frequency ◽  
Morphological Differentiation ◽  
Genotypic Diversity ◽  
Allozyme Variation ◽  
Low Levels

Allozyme variation in 11 Minnesota populations of Lemna minor L. was studied, using 11 enzyme systems, resolving 16 putative loci from 285 plants. Significant deviations from Hardy–Weinberg frequencies occurred in several populations that had excesses of heterozygotes at several loci. While genotypic diversity and evenness measures are similar to other vegetatively reproducing plants (D = 0.541, E = 0.607), very few multilocus genotypes per population were found (mean = 4.0). Substantial population structure was evident (FST = 0.407), apparently reflecting low levels of gene flow (Nm = 0.30) despite the capacity of this species for dispersal of plantlets. This low level of gene flow and apparent low frequency of sexual reproduction has produced substantial levels of genetic divergence among populations, despite an absence of morphological differentiation. Keywords: allozymes, genetic structure, hydrophily, Lemna, vegetative dispersal, vegetative reproduction.

EML Thoron Gas Measurements

1994 ◽  
Vol 56 (1-4) ◽  
pp. 263-266 ◽  
Author(s):  
E.O. Knutson ◽  
A.C. George ◽  
P. Shebell ◽  
C.V. Gogolak
Keyword(s):  
Indoor Air ◽  
Air Flow ◽  
The Other ◽  
Coincidence Method ◽  
Flow Paths ◽  
Filter Tube ◽  
Current Measuring ◽  
Low Levels ◽  
Gas Measurements ◽  
Indoor Air Flow

Abstract The Environmental Measurements Laboratory's experience with two methods of measuring thoron gas, and its findings on the feasibility of using these measurements to diagnose indoor air flow paths, are presented. One method is an updated version of the two-filter tube, and the other is a modified Falk-More-Nyblom delayed coincidence method. Measurements made with these instruments in six houses indicated that thoron concentrations are very low (median about 11 Bq.m-3); this is consistent with values previously reported for US housing. Both methods had difficulty measuring these low levels, particularly in houses with high radon gas levels. At one house, thoron levels measured outdoors over bare earth were higher than indoor levels. At the low levels encountered and with the current measuring technology, it seems unlikely that thoron gas measurements can be used to trace indoor air motion.

FACTOR V LEVELS IN THE NEONATAL PERIOD

PEDIATRICS ◽  
1955 ◽  
Vol 15 (2) ◽  
pp. 180-184
Author(s):  
Lyonel G. Israels ◽  
Alvin Zipursky ◽  
Colin Sinclair
Keyword(s):  
Neonatal Period ◽  
The Other ◽  
Factor V ◽  
Clotting Factors ◽  
Low Levels ◽  
Plasma Activity

Utilizing a modification of the 1-stage method of Wolff, the plasma activity of Factor V was estimated in 53 normal newborns during the first week of life. By this method many newborns were found to have low levels of Factor V during the first 2 days of life which rose towards normal by the sixth day. These findings are discussed with reference to previous findings and to the variations in the other clotting factors during the neonatal period.

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