Mother-daughter correlations

Fig. 4.7 Heritability of host selection behavior in bark beetles a) Mother-daughter correlations of gallery construction in endemic D. rufipennis. Closed circles indicate multiple data points (with permission from the EcoL Soc. America) b) Selection for degree of aversion to alpha-pinene in 1. pini (with permission from the EntomoL Soc. America).

First studies of the aqueous phase chemistry of element 105 were conducted by Gregorich et al. (1988). Like Nb and Ta, Db was adsorbed on glass surfaces upon fuming with nitric acid. In 801 manually performed experiments, 24 a events due to the decay of 34 s Db or its 3.9 s Lr daughter including five aoc mother-daughter correlations were observed. In an attempt to study the extraction of the dubnium fluoride complex from 3.8 M HNO3/I.I M HF into methyl isobutyl ketone (MIBK), no decays attributable to Db could be observed. 

Sg decays were identified by observing correlations of mother-daughter decay events (a or s.f.). 

There might also be systematic errors like, for example, erroneous assignment of mother-daughter decay correlations or random coincidences. Such problems are... 

Three correlated aa-mother-daughter decays were observed that were assigned to the decay of and No as the decay products of Sg. The three correlated events have to be compared with an expectation value of 0.27 for random correlations. This gives a probability of 0.24% that the three events are random correlations. As the mother decays were not observed, it is important to note that and can only be observed if Sg... 

Six a singles in the Ta fraction and 12 in the Nb/Pa fraction were registered with life times compatible with the 34-s Db. In addition, three pairs of correlated mother-daughter decays were registered, one in the Ta fraction and two in the Nb/Pa fraction. From this distribution, the value of 438+jgg for element 105 in 6 M HCl was deduced [79], see Fig. 25. This value is much larger than that of Ta (22), smaller or equal to that of Nb (680), and smaller than that of Pa (1440). 

The genetic correlations of the radionuclides within the families are often characterized by the terms mother and daughter . Thus, is the mother nuclide of all members of the uranium family, Ra is the mother nuclide of Rn, and so forth. 

Self-conscious anxiety, associated with the developmental changes just described, can be exacerbated by parental over-concern, particularly by mothers. Such over-concern occurs more frequently in mothers who themselves have, or have had, an eating disorder or who have been obese. As most family studies have been correlational, it is difficult to know whether family dysfunction contributes to the eating disorder, whether the distortions of eating behaviour in the affected daughter causes the family dysfunction, or whether some common other factor contributes to both (Polivy and Herman 2002). 

Positive coefficients of correlation between the life spans of sister cells have been observed in the bacteria by Koch and Schaechter (K3) and by Kubitschek (K5). A negative coefficient of correlation between the life spans of mother and daughter cells is reported by Koch and Schaechter (K3). They also find that in the organisms they studied, cells divided into nearly equal parts on fission. Hence, the experimental observations indicate that the first extreme mentioned above is more nearly correct. It is important to note that the theory predicts the correlations described without having to postulate any genetic inhomogeneity of the population i.e., all cells may be of the same genotype. 

As observed earlier, in a bacterial population the life spans of the mother and daughter cells are negatively correlated, while those of sister cells are positively correlated. We show next that the negative correlation between mother and daughter is easily accounted for with the usual framework of population balance. The positive correlation between siblings, however, requires the framework just described in Section 7.5.1. We consider first the formulation to account for the negative correlation between mother and daughter. 

Since it is of interest to account for the mother s life span in assessing the division rate, we define a division rate conditional on the life span of the mother cell from which the cell in question has descended. Thus, we let be the division rate of a cell of age t given that its mother s life span is T. In order to account for the negative correlation between the life spans of mother and daughter, must be chosen to fit the experimentally... 

The correlation between life spans of this generation of daughters and those of the mothers from the previous generation then clearly depends on the distribution of the life span We do not wish to pursue this characterization of correlation between mother and daughter any further. 

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