141 research outputs found
Attachment security and maternal behaviors as predictors of children's psychosocial adjustment at school entry
Objective. This paper aimed to examine the contributions of a second assessment time point of attachment security, along with assessments of maternal behavior (sensitivity and autonomy support), to the prediction of childrenâs behavior problems. Design. Maternal behavior and motherâchild attachment were assessed in 73 motherâchild dyads when children were between 15 months and 26 months old. Childrenâs internalizing and externalizing problems were reported by their teachers in kindergarten and first grade. Results. Each assessment time point of attachment security, as well as maternal behavior, explained comparable portions of the variance in childrenâs anxious/depressed behavior, jointly predicting more than three times the variance explained by either measure of attachment alone. Conclusion. Researchers should consider a multidimensional approach to the assessment of the quality of motherâchild relationships, at least when attempting to explain the development of child internalizing problems
Maternal mind-mindedness and childrenâs school readiness: A longitudinal study of developmental processes
This study aimed to test a five-wave sequential mediation model linking maternal mind-mindedness during infancy to childrenâs school readiness in kindergarten through a serial mediation involving child language and effortful control in toddlerhood and the preschool years. Among a sample of 204 mother-child dyads, we assessed maternal mind-mindedness when children were aged 1 year, child expressive vocabulary at age 2, effortful control at ages 3 and 4, and finally cognitive school readiness in kindergarten. The results corroborated the model, suggesting that the prospective association between early mind-mindedness and later cognitive school readiness was entirely mediated by the proposed sequence of mediators, all of which were necessary to account for this longitudinal association. These findings suggest that the potential of parental mind-mindedness to support childrenâs cognitive development may have been under-estimated, and that its putative positive influence may take the form of a developmental cascade unfolding during the preschool years and entailing the acquisition of basic skills that serve as building blocks for further learning and development
Attachment working models as unconscious structures: An experimental test
Internal working models of attachment (IWMs) are presumed to be largely unconscious representations of childhood attachment experiences. Several instruments have been developed to assess IWMs; some of them are based on self-report and others on narrative interview techniques. This study investigated the capacity of a self-report measure, the Inventory of Parent and Peer Attachment (IPPA; Armsden & Greenberg, 1987), and of a narrative interview method, the Adult Attachment Interview (AAI; George, Kaplan, & Main, 1985), to measure unconscious attachment models. We compared scores on the two attachment instruments to response latencies in an attachment priming task. It was shown that attachment organisation assessed by the AAI correlates with priming effects, whereas the IPPA scales were inversely or not related to priming. The results are interpreted as support for the assumption that the AAI assesses, to a certain degree, unconscious working models of attachment
Mécanismes moléculaires de la réplication préférentielle du VIH-1 dans les cellules à polarisation Th1Th17 versus Th1 : rÎle de PPARG dans la régulation négative de la réplication virale
Les cellules T CD4+ humaines sont hĂ©tĂ©rogĂšnes du point de vue de la permissivitĂ© Ă lâinfection par le virus de lâimmunodĂ©ficience humaine de type 1 (VIH-1). Notre laboratoire a prĂ©alablement dĂ©montrĂ© que les cellules Th1 Ă phĂ©notype CXCR3+CCR6- sont relativement rĂ©sistantes Ă lâinfection par le VIH-1 alors que les cellules Th1Th17 Ă phĂ©notype CXCR3+CCR6+ y sont hautement permissives. La rĂ©plication du VIH dĂ©pend de plusieurs facteurs cellulaires de restriction ou de permissivitĂ© agissant Ă diffĂ©rentes Ă©tapes du cycle viral. Toutefois, malgrĂ© plusieurs avancĂ©es, la comprĂ©hension des voies de signalisation cellulaire impliquĂ©es dans la rĂ©gulation de la rĂ©plication du VIH est encore limitĂ©e. Lâobjectif majeur de ce projet de maĂźtrise est de caractĂ©riser les mĂ©canismes molĂ©culaires de la permissivitĂ© et de la rĂ©sistance au VIH respectivement dans les cellules Th1Th17 et Th1. Ce mĂ©moire est divisĂ© en quatre parties qui visent: (i) lâidentification des voies canoniques et des fonctions biologiques diffĂ©remment rĂ©gulĂ©es dans les cellules Th1Th17 versus Th1 par lâanalyse de leur transcriptome au niveau du gĂ©nome entier; (ii) la validation de lâexpression diffĂ©rentielle des gĂšnes dâintĂ©rĂȘt identifiĂ©s par biopuces au niveau des transcrits et des protĂ©ines; (iii) la caractĂ©risation du rĂŽle fonctionnel de certains de ces facteurs (i.e., PPARG, AhR) sur la rĂ©plication du VIH dans les cellules Th1Th17 versus Th1; et (iv) lâidentification du niveau auquel ces facteurs interfĂšrent avec le cycle de rĂ©plication du VIH. Nos rĂ©sultats dâanalyse du transcriptome du gĂ©nome entier par Gene Set Enrichment Analysis et Ingenuity Pathway Analysis indiquent que les cellules Ă profil Th1Th17 sont plus susceptibles Ă lâactivation cellulaire et Ă lâapoptose, favorisent plus lâinflammation et expriment moins fortement les gĂšnes liĂ©s Ă la dĂ©gradation protĂ©osomale comparĂ© aux cellules Ă profil Th1. Ces diffĂ©rences dans la rĂ©gulation de diverses voies et fonctions biologiques permettent en partie dâexpliquer la susceptibilitĂ© Ă lâinfection par le VIH dans ces cellules. Nous avons ensuite confirmĂ© lâexpression diffĂ©rentielle de certains gĂšnes dâintĂ©rĂȘt dans les cellules Th1Th17 (CXCR6, PPARG, ARNTL, CTSH, PTPN13, MAP3K4) versus Th1 (SERPINB6, PTK2) au niveau de lâARNm et des protĂ©ines. Finalement, nous avons dĂ©montrĂ© le rĂŽle des facteurs de transcription PPARG et AhR dans la rĂ©gulation de la rĂ©plication du VIH. Lâactivation de la voie PPARG par la rosiglitazone induit la diminution importante de la rĂ©plication du VIH dans les cellules T CD4+, alors que lâactivation de la voie AhR par les ligands exogĂšnes TCDD et FICZ augmente de façon significative la rĂ©plication virale. Nous proposons que la voie PPARG agit comme un rĂ©gulateur nĂ©gatif de la rĂ©plication du VIH dans ces cellules, en interfĂ©rant avec la polarisation Th17 et probablement en inhibant lâactivitĂ© transcriptionnelle du facteur NF-kB. Les rĂŽles des formes nuclĂ©aires versus cytoplasmiques du rĂ©cepteur Ahr semblent ĂȘtre diamĂ©tralement opposĂ©s, dans la mesure oĂč lâinterfĂ©rence ARN contre AhR sâassocie Ă©galement Ă lâaugmentation de la rĂ©plication virale. Il est ainsi possible que la forme cytoplasmique dâAhR, connue par son activitĂ© E3 ligase, participe Ă la dĂ©gradation protĂ©osomale des particules virales. Le mĂ©canisme par lequel le AhR nuclĂ©aire versus cytoplasmique interfĂšre avec la rĂ©plication virale est en cours dâĂ©tude au laboratoire. Cette Ă©tude reprĂ©sente la premiĂšre caractĂ©risation de lâexpression diffĂ©rentielle de gĂšnes au niveau du gĂ©nome entier de sous-populations T CD4+ permissives versus rĂ©sistantes Ă lâinfection par le VIH. Nos rĂ©sultats identifient de nouvelles cibles molĂ©culaires pour de nouvelles stratĂ©gies thĂ©rapeutiques visant Ă limiter la rĂ©plication du VIH dans les lymphocytes T CD4+ primaires.Human CD4+ T cells are heterogeneous in terms of permissiveness to infection by the human immunodeficiency virus type 1 (HIV-1). Our laboratory previously demonstrated that Th1 cells (CXCR3+CCR6- phenotype) are relatively resistant to infection, whereas Th1Th17 cells (CXCR3+CCR6+ phenotype) are highly permissive to HIV-1. HIV replication depends on several cellular restriction or permissiveness factors acting at different stages of the viral life cycle. However, despite several advances, our knowledge on signaling pathways involved in HIV replication is still limited. The main objective of this MSc degree project is to characterize the molecular mechanisms of permissiveness and resistance to HIV in Th1Th17 and Th1 cells respectively. This thesis is divided into four parts, aiming at : (i) the identification of canonical pathways and biological functions differentially regulated in Th1Th17 vs Th1 cells through the analysis of their whole genome transcriptome; (ii) the validation of differential expression of relevant genes identified by microarrays at mRNA and protein levels; (iii) the characterization of the functional role of some of these factors (i.e. PPARG, AhR) on HIV replication in Th1Th17 versus Th1 cells; and (iv) the identification of the level at which these factors interfere with the HIV replication cycle. Our analysis of the large sets of microarray data by Gene Set Enrichment Analysis and Ingenuity Pathway Analysis indicate that Th1Th17 compared to Th1 cells are more susceptible to cell activation and apoptosis, promote superior inflammation and express at low levels genes related to the proteosomal degradation. These differences in the regulation of various biological functions and pathways can partly explain the susceptibility to HIV infection in these cells. We then confirmed the differential expression of some genes of interest in Th1Th17 (CXCR6, PPARG, ARNTL, CTSH, PTPN13, MAP3K4) versus Th1 (SERPINB6, PTK2) cells at mRNA and protein levels. Finally, we demonstrated the role of the transcription factors PPARG and AhR in the regulation of HIV replication. The activation of PPARG by rosiglitazone induces an important decrease in HIV replication in CD4+ T cells, while AhR activation by its exogenous ligands TCDD and FICZ promotes viral replication. We propose that the PPARG pathway acts as a negative regulator of HIV replication in these cells by interfering with Th17 polarization and probably by inhibiting the transcriptional activity of NF-kB. The role of nuclear versus cytoplasmic AhR appears diametrically opposed, since RNA interference against AhR is also associated with a significant increase in HIV replication. It is thus possible that the cytoplasmic form of AhR, known for its E3 ubiquitine ligase activity, is involved in proteasomal degradation of the viral particles. The mechanism by which the nuclear versus cytoplasmic form of AhR interferes with viral replication is being studied in the laboratory. This study represents the first characterization of the differential expression of genes in the entire genome of CD4+ T subpopulations permissive (Th1Th17) versus resistant (Th1) to infection by HIV. Ours results identify new molecular targets for therapeutic strategies to limit HIV replication in primary CD4+ T lymphocytes
L'organisation cognitive du systÚme d'attachement en tant que prédicteur des perceptions de soutien social et des comportements de recherche d'aide à l'adolescence
L'objectif gĂ©nĂ©ral de ce mĂ©moire est d'Ă©tudier la relation prĂ©dictive entre l'organisation cognitive du systĂšme d'attachement Ă l'adolescence et les perceptions et comportements de soutien social. Le premier article fait le point sur l'Ă©tat actuel de la recherche concernant le Adult Attachement Interview (AAI), c'est-Ă -dire ses fondements thĂ©oriques, ses qualitĂ©s mĂ©trologiques et ses champs d'application. Le deuxiĂšme article est de nature empirique et Ă©tudie la capacitĂ© de l'organisation cognitive du systĂšme d'attachement de prĂ©dire les perceptions de soutien social(PSS) et les comportements de recherche d'aide. Trente-six collĂ©giens sont rencontrĂ©s en entrevue(AAI), dont 28 complĂštent des questionnaires de PSS. Les 36 sujets rĂ©fĂšrent Ă©galement un pair qui complĂšte des questionnaires de recherche d'aide. l'organisation cognitive du systĂšme d'attachement prĂ©dit le dĂ©sir d'ĂȘtre aidĂ©, la satisfaction et l'importance accordĂ©e au soutien, la confiance envers l'aidant, et le recours Ă l'aide des professeurs
L'utilisation des TIC à des fins de harcÚlement criminel en situation de violence conjugale: la théorie des opportunités et des activités routiniÚres de Cohen et Felson (1978) remaniée
Travail-dirigĂ© prĂ©sentĂ© Ă la FacultĂ© des Ă©tudes supĂ©rieures et postdoctorales en vue de lâobtention du grade de MaĂźtre Ăšs sciences (M.Sc.) en criminologie, option criminalistique et informationIntroduite en 1978, la thĂ©orie des opportunitĂ©s et des activitĂ©s routiniĂšres de Cohen et Felson demeure encore aujourdâhui une des plus citĂ©es pour expliquer la commission dâactes criminels qui, pour leur part, ne cessent dâĂ©voluer au fil du temps. Lâintroduction des technologies de lâinformation et des communications, les TIC, a ainsi contribuĂ© Ă grandement changer le portrait de diverses formes de criminalitĂ© traditionnelle, notamment celui du harcĂšlement criminel. Les TIC sont, entre autres, de plus en plus utilisĂ©es dans le cas de violences conjugales pour commettre du harcĂšlement auprĂšs des victimes, et ce, mĂȘme lorsque celles-ci vont chercher refuge en maison dâhĂ©bergement. Cette nouvelle rĂ©alitĂ© est dĂ©noncĂ©e par les intervenantes et les directrices de maisons dâhĂ©bergement qui y voient une vĂ©ritable menace non seulement pour les femmes, mais aussi pour la maison dâhĂ©bergement et pour leurs interventions.
Avec la collaboration de policiers, dâun professeur de lâĂcole des sciences criminelles de Lausanne et dâintervenantes en maison dâhĂ©bergement pour femmes victimes de violence conjugale, une collecte des donnĂ©es a Ă©tĂ© menĂ©e afin de prĂ©ciser comment la thĂ©orie des opportunitĂ©s et des activitĂ©s routiniĂšres de Cohen et Felson peut ĂȘtre adaptĂ©e dans les cas de harcĂšlement criminel par le biais des TIC, en situation de violence conjugale post- sĂ©paration, lorsque les femmes sont accueillies en maisons dâhĂ©bergement. Le crime ciblĂ© par cette Ă©tude, le harcĂšlement criminel, est dâabord explicitĂ© Ă partir du point de vue lĂ©gal, puis Ă partir de la comprĂ©hension quâen ont les policiers et les intervenantes en maison dâhĂ©bergement, afin dâen connaitre les particularitĂ©s.
Dans le cadre de cette Ă©tude, le dĂ©linquant motivĂ© sâavĂšre ĂȘtre le conjoint cherchant Ă contrĂŽler sa victime en utilisant diverses technologies pour lâĂ©pier et la harceler mĂȘme si elle a quittĂ© le domicile familial et la situation de violence conjugale, pour se rĂ©fugier en maison dâhĂ©bergement. La cible attrayante se trouve alors ĂȘtre la conjointe rendue vulnĂ©rable par lâĂ©tat Ă©motionnel dans lequel elle est plongĂ©e par les agissements du conjoint. Les maisons dâhĂ©bergement pour femmes victimes de violence conjugale ainsi que lâenquĂȘte policiĂšre sont vues comme pouvant jouer un rĂŽle de gardien efficace dans une telle situation. En effet, les femmes en maison dâhĂ©bergement se voient offrir la possibilitĂ© de se couper de toutes formes de technologies leur appartenant susceptibles de les mettre en danger. Ă lâinverse, bien utilisĂ©es, les TIC peuvent sâavĂ©rer une source de donnĂ©es riches en informations permettant de « mettre en boĂźte » lâagresseur, en utilisant les traces numĂ©riques que laisse lâutilisation des TIC pour constituer la preuve du dĂ©lit.
Ainsi se trouve revisitĂ©e la thĂ©orie de Cohen et Felson Ă lâĂšre des TIC et se cĂ©lĂšbre la rencontre entre criminologie et criminalistique.Introduced in 1978, the lifestyle and routine activities theory of Cohen and Felson remains one of the most cited theory to explain criminal activities. The use of information and communication technologies (ICT) has transformed traditional forms of crime, such as criminal stalking and harassment. The ICT are often used in domestic violence cases to harass and stalk the victim, even when she is seeking security in shelters. This problematic was brought to our attention by shelter workers, who consider those technologies an actual threat for women and their children, but also for the shelter and the interventions.
With the collaboration of police investigators, a professor from the Ăcole des sciences criminelles de Lausanne and shelter workers, data were collected through interviews then analyzed, in order to adapt the Cohen and Felsonâs lifestyle and routine activities theory in cases of ICT use for stalking, in intimate partner violence relationships. The crime targeted by this study, criminal stalking and harassment committed through ICT, is developed according to the Criminal Code but also according to the police officer and the shelter workers, to understand its particularities.
In this study, the motivated offender is the partner controlling his wife using various devices to track and harass her, even when she quit the violent situation to seek security in a shelter. In this case, her unstable emotional state and the fact that her partner knows her well make the present or former wife vulnerable and, therefore, a suitable target. Also, the emotional context surrounding the domestic violence situation can destabilize her when she receives text messages or e-mails from her partner, trying to convince her to come back. Finally, shelters and the police investigation are there seen as a capable guardian. In fact, women in shelters have the possibility to turn off their technology in a secure environment where they can get the support they need. Even if the ICT can, in one hand, impede the intervention, it can also be a rich source of information, on the other hand. Indeed, when a police investigation takes place, this digital information can be used as evidence in criminal court to prove the stalking.
Thereby, Cohen and Felsonâs theory of opportunities and routine activity is revisited in the ICT era and put forward the meeting of criminological and forensic science
Disentangling the direction of associations between sleep and temperament in toddlers
Objectives/Background: Although much research has investigated the associations between
childrenâs sleep and their temperament, the direction of these associations remains unclear,
largely due to a lack of longitudinal studies with repeated assessments of both sleep and
temperament. Aiming to clarify the temporal precedence of these two constructs, the current
study investigated reciprocal associations between toddlersâ sleep and temperament with a
longitudinal design. Participants: The sample consisted of 82 toddlers (39 girls) assessed twice.
Methods: At both 2 (M = 25.23 months; SD = 1.11) and 3 years of age (M = 36.81 months; SD =
0.91), toddlers' sleep duration and quality were assessed using actigraphy and their temperament
was reported by their mothers with the Toddler Behavior Assessment Questionnaire. Results:
Shorter nighttime sleep duration (Ă = -.28, p = .03) and lower sleep efficiency (Ă = -.33, p = .01)
at 2 years predicted more temperamental proneness to anger at 3 years, while greater
temperamental social fear at 2 years was predictive of shorter 24-hour (Ă = -.44, p = .02) and
nighttime (Ă = -.36, p = .04) sleep duration at 3 years. Associations between temperamental
activity level and sleep variables were non-significant. Conclusion: The direction of the
associations between toddlersâ sleep and their temperament may vary according to which
dimension of temperament is considered. These findings should encourage practitioners to
identify the beginning of the causal chain leading to sleep or temperamental difficulties so as to
develop well-tailored intervention plans
From early relationships to preacademic knowledge : a socio-cognitive developmental cascade to school readiness
This study aimed to test a four-wave sequential mediation model linking motherâchild
attachment to childrenâs school readiness through child executive functioning (EF) and
prosociality in toddlerhood and the preschool years. Motherâchild attachment security was
assessed when children (N = 255) were aged 15 months and 2 years, child EF at age 2, prosocial
behavior at age 4, and finally cognitive school readiness in kindergarten (age 6). The results
revealed three indirect pathways linking attachment to school readiness: one through EF only,
one through prosocial behavior only, and a last pathway involving both EF and prosocial
behavior serially. These findings suggest that secure attachment may equip children with both
cognitive and social skills that are instrumental to their preparedness for school
The role of paternal mindâmindedness in preschoolers' selfâregulated conduct
This study examined the prospective links between paternal mindâmindedness (MM) and 2 indices of preschoolers' selfâregulated con-duct, namely, inhibitory control and ruleâcompatible conduct.Ninetyâtwo families (47 boys) participated in 2 assessments. PaternalMM was assessed with a 10âmin fatherâchild freeâplay session whenchildren were aged 18 months. Children's ruleâcompatible conductwas reported by mothers when children reached 3 years of age,and inhibitory control was measured with a Snack Delay task, alsoadministered at 3 years. The results suggested that after accountingfor the contribution of child temperament (social fearfulness),paternal MM was positively related to children's inhibitory control.In contrast, the relation between paternal MM and motherâreportedruleâcompatible conduct was not significant. The results areinterpreted in light of the mechanisms that may account for the linksbetween paternal MM and preschoolers' emerging capacity tovoluntarily control their behaviour
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