Origin of uranium isotope variations in early solar nebula condensates

High-temperature condensates found in meteorites display uranium isotopic variations (^(235)U/^(238)U), which complicate dating the solar system’s formation and whose origin remains mysterious. It is possible that these variations are due to the decay of the short-lived radionuclide ^(247)Cm (t_(1/2) = 15.6 My) into ^(235)U, but they could also be due to uranium kinetic isotopic fractionation during condensation. We report uranium isotope measurements of meteoritic refractory inclusions that reveal excesses of ^(235)U reaching ~+6% relative to average solar system composition, which can only be due to the decay of ^(247)Cm. This allows us to constrain the ^(247)Cm/^(235)U ratio at solar system formation to (7.0 ± 1.6) × 10^(−5). This value provides new clues on the universality of the nucleosynthetic r-process of rapid neutron capture

The Diaper Change Play: Validation of a New Observational Assessment Tool for Early Triadic Family Interactions in the First Month Postpartum

The quality of family relations, observed during mother-father-infant triadic interactions, has been shown to be an important contributor to child social and affective development, beyond the quality of dyadic mother-child, father-child, and marital relationships. Triadic interactions have been well described in families with 3 month olds and older children using the Lausanne Trilogue Play (LTP). Little is known about the development of mother-father-baby interactions in the very 1st weeks postpartum, mostly because no specific observational setting or particular instrument had been designed to cover this age yet. To fill this gap, we adapted the LTP to create a new observational setting, namely the Diaper Change Play (DCP). Interactions are assessed using the Family Alliance Assessment Scales for DCP (FAAS-DCP). We present the validation of the DCP and its coding system, the FAAS-DCP. The three validation studies presented here (44 mother-father-child-triads) involve a sample of parents with 3-week-old infants recruited in two maternity wards (n = 32 and n = 12) in Switzerland. Infants from both sites were all healthy according to their APGAR scores, weight at birth, and scores on the NICU Network Neurobehavioral Scale (NNNS), which was additionally conducted on the twelve infants recruited in one of the maternity ward. Results showed that the "FAAS -DCP" coding system has good psychometric properties, with a good internal consistency and a satisfying reliability among the three independent raters. Finally, the "FAAS-DCP" scores on the interactive dimensions are comparable to the similar dimensions in the FAAS-LTP. The results showed that there is no statistically significant difference on scores between the "FAAS-DCP" and the "FAAS," which is consistent with previous studies underlying stability in triadic interaction patterns from pregnancy to 18 months. These first results indicated that the DCP is a promising observational setting, able to assess the development of the early family triadic functioning. The DCP and the FAAS-DCP offer to both clinicians and researchers a way to improve the understanding of the establishment of early family functioning as well as to study the young infant's triangular capacity. Perspectives for future research will be discussed

Distinct ^(238)U/^(235)U ratios and REE patterns in plutonic and volcanic angrites: Geochronologic implications and evidence for U isotope fractionation during magmatic processes

Angrites are differentiated meteorites that formed between 4 and 11 Myr after Solar Systemformation, when several short-lived nuclides (e.g., ^(26)Al-^(26)Mg, ^(53)Mn-^(53)Cr, ^(182)Hf-^(182)W) were still alive. As such, angrites are prime anchors to tie the relative chronology inferred from these short-lived radionuclides to the absolute Pb-Pb clock. The discovery of variable U isotopic composition (at the sub-permil level) calls for a revision of Pb-Pb ages calculated using an “assumed” constant ^(238)U/^(235)U ratio (i.e., Pb-Pb ages published before 2009–2010). In this paper, we report high-precision U isotope measurement for six angrite samples (NWA 4590, NWA 4801, NWA 6291, Angra dos Reis, D’Orbigny, and Sahara 99555) using multi-collector inductively coupled plasma mass-spectrometry and the IRMM-3636 U double-spike. The age corrections range from −0.17 to −1.20 Myr depending on the samples. After correction, concordance between the revised Pb-Pb and Hf-W and Mn-Cr ages of plutonic and quenched angrites is good, and the initial (^(53)Mn/^(55)Mn)_0 ratio in the Early Solar System (ESS) is recalculated as being (7 ± 1) × 10^(−6) at the formation of the Solar System (the error bar incorporates uncertainty in the absolute age of Calcium, Aluminum-rich inclusions – CAIs). An uncertainty remains as to whether the Al-Mg and Pb-Pb systems agree in large part due to uncertainties in the Pb-Pb age of CAIs. A systematic difference is found in the U isotopic compositions of quenched and plutonic angrites of +0.17‰. A difference is also found between the rare earth element (REE) patterns of these two angrite subgroups. The δ^(238)U values are consistent with fractionationduring magmatic evolution of the angrite parent melt. Stable U isotope fractionation due to a change in the coordination environment of U during incorporation into pyroxene could be responsible for such a fractionation. In this context, Pb-Pb ages derived from pyroxenes fraction should be corrected using the U isotope composition measured in the same pyroxene fraction

The Family Alliance Assessment Scales: Steps Toward Validity and Reliability of an Observational Assessment Tool for Early Family Interactions

We present the first steps in the validation of an observational tool for father-mother-infant interactions: the FAAS (Family Alliance Assessment Scales). Family-level variables are acknowledged as unique contributors to the understanding of the socio-affective development of the child, yet producing reliable assessments of family-level interactions poses a methodological challenge. There is, therefore, a clear need for a validated and clinically relevant tool. This validation study has been carried out on three samples: one non-referred sample, of families taking part in a study on the transition to parenthood (normative sample; n=30), one referred for medically assisted procreation (infertility sample; n=30) and one referred for a psychiatric condition in one parent (clinical sample; n=15). Results show that the FAAS scales have (1) good inter-rater reliability and (2) good validity, as assessed through known-group validity by comparing the three samples and through concurrent validity by checking family interactions against parents' self-reported marital satisfactio

Validation of the French Version of the Experiences in Close Relationships– Revised (ECR-R) Adult Romantic Attachment Questionnaire

This study aimed to validate the French version of the Experiences in Close Relationships-Revised (ECR-R) adult attachment questionnaire by investigating its internal structure and construct validity. The sample (N = 600) consisted of an equal number of male and female participants aged 25-45 years. Variables linked to adult romantic attachment (marital satisfaction, sexual satisfaction and fears associated with sexual activities, and self-esteem) were assessed using a set of questionnaires. The reliability of the two attachment dimensions (viz., avoidance and anxiety) was satisfactory. Confirmatory factor analyses revealed that the original two-factor model explained the data collected with the French ECR-R most satisfactorily. The assessment of measurement invariance showed that the structure is the same across the original U. S. sample and our sample, across men and women, and across single individuals and those in a couple relationship. Our evaluation of construct validity showed that the higher avoidance and anxiety, the lower self-esteem and sexual satisfaction and the higher the fears associated with sexuality. These results are theoretically coherent and consistent with those of previous studies of the English version of the scale. We conclude that the French version is valid

The Family Alliance Model: A Way to Study and Characterize Early Family Interactions

The aim of this paper is to present the family alliance (FA) model, which is designed to conceptualize the relational dynamics in the early family. FA is defined as the coordination a family can reach when fulfilling a task, such as playing a game or having a meal. According to the model, being coordinated as a family depends on four interactive functions: participation (all members are included), organization (members assume differentiated roles), focalization (family shares a common theme of activity), affect sharing (there is empathy between members). The functions are operationalized through the spatiotemporal characteristics of non-verbal interactions: for example, distance between the partners, orientation of their bodies, congruence within body segments, signals of readiness to interact, joint attention, facial expressions. Several standardized observational situations have been designed to assess FA: The Lausanne Trilogue Play (with its different versions), in which mother, father, and baby interact in all possible configurations of a triad, and the PicNic Game for families with several children. Studies in samples of non-referred and referred families (for infant or parental psychopathology) have highlighted different types of FA: disorganized, conflicted, and cooperative. The type of FA in a given family is stable through the first years and is predictive of developmental outcomes in children, such as psychofunctional symptoms, understanding of complex emotions, and Theory of Mind development

Parental sensitivity, family alliance and infants' vagal tone: Influences of early family interactions on physiological emotion regulation

In this study, we investigated the influence of parental sensitivity and family alliance on infants’ vagal tone, considered as a physiological indicator of emotion regulation. Studies on mother–infant interactions have shown that vagal tone can be influenced by the quality of the interaction, such as interacting with a sensitive mother. To date, no study has investigated the influence of paternal sensitivity or family alliance on infants’ vagal tone. We hypothesized that maternal sensitivity, paternal sensitivity, and family alliance would be associated with infants’ vagal tone during dyadic and triadic interactions. We also explored if family alliance would act as a moderator on the association between parental sensitivity and vagal tone and if the sensitivity of both parents would act as a moderator on the association between family alliance and vagal tone. This study took place in Switzerland and included 82 families with their 3–4-month-old infants. Results showed that maternal sensitivity and family alliance were associated with infants’ vagal tone, but paternal sensitivity was not. We found no significant moderation effect. However, result tendencies suggested that the contribution of paternal sensitivity to infants’ emotion regulation could be influenced by family alliance, whereas maternal sensitivity and family alliance have a unique contribution

Distribution Coefficients of the REEs, Sr, Y, Ba, Th, and U between α-HIBA and AG50W-X8 Resin

Rare-earth elements (REEs) are known for their similar behaviors, which make their purification through chromatographic techniques particularly challenging. The use of α-hydroxyisobutyric acid (α-HIBA) in combination with a cation-exchange resin is perhaps the most widely used chromatographic technique to separate individual REEs from each other. However, only limited REE partition data between α-HIBA and cation resins exist, which makes it challenging to develop and optimize purification techniques using this platform. Here, we report distribution coefficients (K_d) of REEs, as well as Sr, Y, Ba, Th, and U, between α-HIBA at pH = 4.50 and AG50W-X8 cation-exchange resin, obtained by batch equilibration experiments. For all 19 elements, the distribution coefficients decrease with increasing acid concentration. For the REEs, a linear relationship is observed in log–log space between K_d values and α-HIBA molarity. While the K_d values have been calibrated at pH = 4.50, formulas are provided allowing recasting of the K_d values at any pH. To test the accuracy of the data, we compare elution curves simulated using the newly determined distribution coefficients to actual elution curves. The close agreement between simulated and experimental elution curves demonstrates that the distribution coefficients obtained in this study are effective to devise multielement extraction and purification scheme for high-precision elemental and isotopic analyses of REEs for various applications