The mental-health consequences of childlessness have been well documented and the perception is that women are more likely than men to experience lower mental well-being, including emotional distress, as a result of childlessness; despite the fact that very few studies have focused on the implications for men. Thus, employing OLS multiple regression we seek to examine: (1) the association between childlessness and emotional distress and whether the risk was greater among men or women. (2) Whether there is significant variation in emotional distress among childless individuals after controlling for socio-demographic factors. The data was derived from the Estonian Health Interview Survey, collected in 2006 and 2007. The survey was a multi-stage random sample of the Estonian Population aged 15-85. Under study was men and women aged 40 and above (N=4294).The outcome variable- emotional distress is based on the emotional state questionnaire (EST-Q), a self-rated health measure. The simple regression and multivariate OLS regressions indicated higher predicted levels of emotional distress symptoms for childless men when compared to childless women. In comparison, the interactions revealed more distress among childless women. Overall, the results garnered indicate that educational attainment and personal income ameliorates the negative mental health consequences of childlessness. However, the degree and manner in which childlessness matter differ by gender, ethnicity and relationship status, but was inconclusive for age. An unexpected finding from the interaction models was the high level of distress among women that were parents. In general, the outcomes point to other reasons for the higher levels of distress among women. The mental-health consequences of childlessness have been well documented and the perception is that women are more likely than men to experience lower mental well-being, including emotional distress, as a result of childlessness; despite the fact that very few studies have focused on the implications for men. Thus, employing OLS multiple regression we seek to examine: (1) the association between childlessness and emotional distress and whether the risk was greater among men or women. (2) Whether there is significant variation in emotional distress among childless individuals after controlling for socio-demographic factors. The data was derived from the Estonian Health Interview Survey, collected in 2006 and 2007. The survey was a multi-stage random sample of the Estonian Population aged 15-85. Under study was men and women aged 40 and above (N=4294).The outcome variable- emotional distress is based on the emotional state questionnaire (EST-Q), a self-rated health measure. The simple regression and multivariate OLS regressions indicated higher predicted levels of emotional distress symptoms for childless men when compared to childless women. In comparison, the interactions revealed more distress among childless women. Overall, the results garnered indicate that educational attainment and personal income ameliorates the negative mental health consequences of childlessness. However, the degree and manner in which childlessness matter differ by gender, ethnicity and relationship status, but was inconclusive for age. An unexpected finding from the interaction models was the high level of distress among women that were parents. In general, the outcomes point to other reasons for the higher levels of distress among women.

From the sexual preselection point of view, understanding sex determination/differentiation mechanisms in the bird is critical in both evolutionary and industrial applications. The chicken embryo provides an unique vertebrate model in the field of development biology. Morphological sex development in the chick gonad starts at 6.5 embryonic day (E6.5), however, genetic sex determination and development should occur earlier. In order to comprehend genes and their underlying mechanisms being involved in sex-determination/development during early embryogenesis, we not only made a male-subtract-female and a female-subtract-male cDNA library as early as embryonic day 3 (E3; Hamburger and Hamilton Stage 20), but also examined early transcripts related to male development in chicken embryo and their expression profiles in this study. A total of 89 and 127 candidates of male-development transcripts represented respectively for 83 known and 119 unknown non-redundant sequences, which were characterized in an E3 male- subtract-female complementary DNA library. In this study, thirty-five selected transcripts being validated by quantitative reverse transcription-polymerase chain reaction that the expression levels of 25 transcripts were higher in male E3 whole embryos than in females (P < 0.05). Notably, twelve of these transcripts mapped to the Z chromosome. At 72 weeks of age, twenty transcripts were expressed at higher levels in testes than in ovaries. Meanwhile, four transcripts were expressed at higher levels in brains of male than in brains of female chickens (P < 0.05). By using of methods of whole mount and frozen cross-section in situ hybridization, the expressions of riboflavin kinase (RFK), WD repeat domain 36 (WDR36) and EY505808 transcripts on E7 chicken male gonads were corroborated to be better than female gonads. This result was confirmed by using of western blotting analysis which also showed the expressions were specifically on gonads than other tissues. Treatment with an aromatase inhibitor formestane at E4 depicted the effect of the expression levels at E7 of the coatomer protein complex (subunit beta 1), solute carrier family 35 member F1, LOC427316 and EY505812 transcripts across both sexes (P < 0.05), which was similar to the observed gene expressions for both doublesex and mab-3 related transcription factor 1 gene. Additionally, the interaction effects of sex with formestane treatment were observed in 15 candidate male development transcripts (P < 0.05). This study demonstrated a panel of potentially candidate male development transcripts being identified during early chicken embryogenesis; some might be regulated by sex hormones.

17q23 amplicon is one of the many chromosomal regions that undergo amplification in breast tumors. Such amplicons harbor proto-oncogenes that may be overexpressed due to gene amplifications. Copy number analysis in breast cancer cell lines and breast tumors identified several independently amplified regions within the 17q23 amplicon, suggesting that a number of genes are selected for amplification as they may independently contribute to tumor formation and progression. To characterize distinct amplicons on 17q23 and localize putative oncogenes, various studies are done on this region. In order to better understand the role of 17q23 amplification in breast cancer, characterizing unidentified genes or ESTs (Expressed Sequence Tags) on the 17q23 amplicon is crucial. In this study, in silico analysis of human (H.sapiens), chimpanzee (P.troglodytes), and mouse (M.musculus) genomes were performed to examine sequence homology between these 3 species for the purpose of identifying novel genes. The objective of this study was to analyze a 50 kb region between TBX2 and TBX4 genes and characterize the EST T02811 located on that region. Analysis and comparisons of these three genomes were established based on genomic sequences and availability of ESTs with gene prediction programs (BLAST, Pipmaker, Vista, GENSCAN etc.). Based on our results, we prepared a homology map between these 3 species, including positions of ESTs that may indicate novel genes. In this 50 kb region, we found in silico and experimantal evidence for the presence of an unidentified gene. We managed to extend the 313 bp EST T02811 size to 1423 bp which we think is as of yet incomplete. Further studies are needed to characterize this novel gene as a potential oncogene candidate. Characterizing the roles of such candidate oncogenes in amplicons will provide a better understanding of genomic amplicon regions and their roles in tumorigenesis.

Diss.--Philosophische Fakultät--Bonn--Rheinische Friedrich-Wilhelms-Universität, 2000. / Bibliogr. p. 529-570. Index.

Dissertation--Paris--Sorbonne, 2003. / Bibliogr. p. 272-280.

Diss.--Frankfurt am Main--Johann Wolfgang Goethe-Universität, 2000. / Bibliogr. p. 219-237. Index.

Texte fortement remanié de: Magisterarbeit--Fakultät für Kulturwissenschaften--Universität Tübingen, 1991. / Bibliogr. p. 69-84.

Texte remanié de: Thèse de doctorat--Histoire--Paris--EHESS, 2001. / Glossaire. IFAS = Institut français d'Afrique du Sud.

D'après la thèse de doctorat--Université de Bâle. / Bibliogr. p. 603-629. Index.

L'abondance du bouleau jaune (Betula alleghaniensis) tend à diminuer dans plusieurs forêts décidues aménagées de l'est de l'Amérique du Nord. Le manque de lits de germination adéquats, notamment une faible exposition du sol minéral, expliquerait en partie cette tendance. Bien que le bois mort soit également reconnu comme étant un lit de germination pour l'espèce, son importance pour le maintien des processus de régénération demeure peu documentée. Par exemple, l'impact du l'identité spécifique du bois mort pour l'établissement et la survie du bouleau jaune n'a que rarement été considéré. De plus, la présence occasionnelle d'une régénération préétablie de bouleau jaune sur bois mort et en sous-couvert amène à penser que ces individus auraient une meilleure capacité de tolérance à l'ombre. Cela dit, les traits morphologiques et l'allocation de la biomasse d'individus juvéniles de bouleau jaune occupant des lits de germination contrastés n'ont jamais été comparés. Le premier objectif de cette étude était de caractériser et comparer les patrons d'établissement du bouleau jaune, en lien avec les lits de germination connus comme étant importants pour cette espèce (bois mort avec ou sans mousse, sol minéral). Un échantillonnage aléatoire a ainsi été réalisé à l'intérieur de 4 érablières à bouleau jaune du sud-ouest du Québec, aménagées par coupes de jardinage (6 et 15 ans). Le lit de germination, le microsite, l'espèce de bois mort et la hauteur de chaque individu répertorié ont été identifiés. En second lieu, un échantillonnage destructif d'individus établis sur bois mort (avec ou sans mousse) et sur sol minéral a été réalisé. Un large gradient de taille (15 à 330 cm) et de lumière (3,5 et 50 % de lumière incidente) a été couvert. Les patrons de croissance, la répartition de biomasse dans les différents compartiments de l'arbre et divers traits morphologiques foliaires et racinaires ont ainsi été comparés en fonction du lit de germination. Nos résultats ont montré que le bois mort soutient une plus grande proportion des individus répertoriés comparativement au sol minéral. Le bois mort provenant des conifères et du bouleau jaune lui-même soutenait une plus grande proportion de ces individus. Les individus établis sur le sol minéral étaient majoritairement localisés sur les sentiers de débardage rendant cette cohorte d'individus sujette à être négativement affectée par la réutilisation de ces sentiers lors de coupes subséquentes. Lié à notre second objectif, il ressort que la taille des individus influence fortement la majorité des paramètres estimés alors que le lit de germination n'avait que relativement peu d'effet direct. Par contre, les individus sur bois mort, en produisant significativement plus de racines fines par unité de biomasse et en conservant une taille plus petite sur une plus longue période de temps, sont plus aptes à survivre en sous couvert forestier. Ces variations intraspécifiques permettent d'amoindrir les effets ontogéniques associés avec une augmentation de taille pour certains paramètres importants (LAR, FRMR). Les semis de bouleau jaune sur bois mort peuvent ainsi conserver une plus grande efficience dans la capture des ressources ce qui affecte positivement leur capacité de tolérance à l'ombre. En somme, nos résultats démontrent que le bois mort du bouleau jaune et d'espèces conifériennes permet de maintenir une abondante régénération naturelle de bouleau jaune bien distribuée au sein des sites. De plus, la présence d'une banque de candidats préétablis et prêts à réagir à une ouverture de couvert forestier y est favorisée. Cet élément structural, important pour les processus de régénération du bouleau jaune, devrait être davantage pris en compte dans une perspective d'aménagement écosystémique des forêts feuillues du Québec. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Betula alleghaniensis, Lit de germination, Identité spécifique du bois mort, Répartition de la biomasse, Effet ontogénique, Coupe de jardinage.