Deformation, acoustic emission and ultrasound velocity during fatigue tests on paper

We study the evolution of mechanical properties of paper samples during cyclic experiments. The issue is to look at the sample-to-sample variation, and we try to predict the number of loading cycles to failure. We used two concurrent methods to obtain the deformation: the strain was calculated from vertical displacement measured by laser interferometer sensor, as well as, computed by digital image correlation technique from pictures taken each 2s by a camera. Acoustic emission of fracture was also recorded, and an active ultrasonic wave method using piezoelectric transducers is used to follow the viscoelastic behaviour of each sample. We found that a sharp final increase of different variables like deformation, strain rate and fluctuations, are signs of an imminent rupture of the paper. Moreover looking at the evolution of these quantities during the first cycle only is already an indicator about the lifetime of the sample.Peer reviewe

Night Awakening in Infancy : Developmental Stability and Longitudinal Associations With Psychomotor Development

Fragmented sleep is common in infancy. Although night awakening is known to decrease with age, in some infants night awakening is more persistent and continues into older ages. However, the influence of fragmented sleep on development is poorly known. In the present study, the longitudinal relationship between fragmented sleep and psychomotor development (Bayley Scales of Infant and Toddler Development [Bayley-III]; Bayley, 2009) was investigated in infants with (>= 3 night awakenings, n = 81) and without fragmented sleep (Peer reviewe

Signaled night awakening and its association with social information processing and socio-emotional development across the first two years

Study objectives: Night awakening is common in infancy, and some infants continue to have signaled night awakenings throughout early childhood. However, the influence of signaled night awakening on children's social development is less explored. In the present study, longitudinal associations between signaled night awakening, social information processing, and socio-emotional development were measured within the CHILD-SLEEP birth cohort in two groups formed based on parent-reported night awakenings. Methods: At 8 months, there were 77 infants in the waking group (≥3 awakenings) and 69 infants in the nonwaking group (≤1 awakening). At 8 and 24 months, social information processing was measured as children's attention to neutral and emotional faces, and at 24 months, parent-reported socio-emotional behavior was measured with the Brief Infant Toddler Social Emotional Assessment (BITSEA) questionnaire. Results: The two groups showed different patterns of attention to emotional faces. The waking group had a more pronounced attentional bias to fearful vs. happy faces, whereas in the nonwaking group, attention to fearful and happy faces did not differ. In addition, at 24 months, the waking group had more dysregulation problems and lower social competence than the nonwaking group, but no clear differences in internalizing or externalizing problems were found. Conclusions: Our results contribute to the literature by showing that during the first two years of life, signaled night awakening is associated with social information processing and socio-emotional behavior.Study objectives: Night awakening is common in infancy, and some infants continue to have signaled night awakenings throughout early childhood. However, the influence of signaled night awakening on children's social development is less explored. In the present study, longitudinal associations between signaled night awakening, social information processing, and socio-emotional development were measured within the CHILD-SLEEP birth cohort in two groups formed based on parent-reported night awakenings. Methods: At 8 months, there were 77 infants in the waking group (≥3 awakenings) and 69 infants in the nonwaking group (≤1 awakening). At 8 and 24 months, social information processing was measured as children's attention to neutral and emotional faces, and at 24 months, parent-reported socio-emotional behavior was measured with the Brief Infant Toddler Social Emotional Assessment (BITSEA) questionnaire. Results: The two groups showed different patterns of attention to emotional faces. The waking group had a more pronounced attentional bias to fearful vs. happy faces, whereas in the nonwaking group, attention to fearful and happy faces did not differ. In addition, at 24 months, the waking group had more dysregulation problems and lower social competence than the nonwaking group, but no clear differences in internalizing or externalizing problems were found. Conclusions: Our results contribute to the literature by showing that during the first two years of life, signaled night awakening is associated with social information processing and socio-emotional behavior.Peer reviewe

Prevalence and evolution of snoring and the associated factors in two-year-old children

Objectives: To evaluate the prevalence and persistence of snoring during the first two years of life in two Finnish birth cohorts and to assess the associated factors. Study design: The study population comprised 947 children from the CHILD-SLEEP (CS) and 1393 children from the FinnBrain (FB) birth cohorts. Questionnaires were provided to both parents when the child was 24 months of age. The questionnaire consisted of parts concerning the child's sleep and environmental factors. Results: The combined prevalence of habitual snoring in the two birth cohorts at the age of 24 months was 2.3% (95% CI 1.5-3.1), which is markedly lower than reported previously. Children suffering from recurrent infections (CS odds ratio (OR) 3.9, 95% CI 1.2-12.5) or asthma (FB OR 4.3, 1.4-13.5) snored habitually more often. Both the mother's (CS OR 3.2, 1.2-9.0) and father's (CS OR 3.4, 1.4-8.0) snoring every night added to the risk of the child snoring. In the multivariate models, parental snoring (CS adjusted odds ratio (ORa) 2.8, 1.1-6.8), the mother's lower level of education (CS ORa 2.9, 1.2-7.5, FB ORa 2.1, 1.0-4.5), and the mother's lower monthly income (FB ORa 2.9, 1.3-6.3) associated with the child's habitual snoring. Conclusions: The prevalence of habitual snoring in two Finnish birth cohorts is lower than reported previously. The independent risk factors for habitual snoring at the age of two years were the parents' snoring and the mother's low income and low education.Objectives: To evaluate the prevalence and persistence of snoring during the first two years of life in two Finnish birth cohorts and to assess the associated factors. Study design: The study population comprised 947 children from the CHILD-SLEEP (CS) and 1393 children from the FinnBrain (FB) birth cohorts. Questionnaires were provided to both parents when the child was 24 months of age. The questionnaire consisted of parts concerning the child's sleep and environmental factors. Results: The combined prevalence of habitual snoring in the two birth cohorts at the age of 24 months was 2.3% (95% CI 1.5-3.1), which is markedly lower than reported previously. Children suffering from recurrent infections (CS odds ratio (OR) 3.9, 95% CI 1.2-12.5) or asthma (FB OR 4.3, 1.4-13.5) snored habitually more often. Both the mother's (CS OR 3.2, 1.2-9.0) and father's (CS OR 3.4, 1.4-8.0) snoring every night added to the risk of the child snoring. In the multivariate models, parental snoring (CS adjusted odds ratio (ORa) 2.8, 1.1-6.8), the mother's lower level of education (CS ORa 2.9, 1.2-7.5, FB ORa 2.1, 1.0-4.5), and the mother's lower monthly income (FB ORa 2.9, 1.3-6.3) associated with the child's habitual snoring. Conclusions: The prevalence of habitual snoring in two Finnish birth cohorts is lower than reported previously. The independent risk factors for habitual snoring at the age of two years were the parents' snoring and the mother's low income and low education. (C) 2021 The Authors. Published by Elsevier B.V.Peer reviewe

Variation near MTNR1A associates with early development and interacts with seasons

Melatonin is a circadian regulatory hormone with neuroprotective properties. We have previously demonstrated the association of the genetic variant rs12506228 near the melatonin receptor 1A gene (MTNR1A) with intolerance to shift‐work. Furthermore, this variant has been connected to Alzheimer's disease. Because of the previously suggested role of melatonin signalling in foetal neurocognitive and sleep development, we studied here the association of rs12506228 with early development. The study sample comprised 8‐month‐old infants from the Finnish CHILD‐SLEEP birth cohort (n = 1,301). Parental questionnaires assessed socioemotional, communication and motor development, as well as sleep length and night awakenings. The A allele of rs12506228 showed an association with slower socioemotional (p = .025) and communication (p = .0098) development, but no direct association with sleep. However, the association of the Finnish seasons with infant sleep length interacted with rs12506228. Taken together, rs12506228 near MTNR1A, which has been previously linked to adult and elderly traits, is shown here to associate with slower early cognitive development. In addition, these results suggest that the darker seasons associate with longer infant sleep time, but only in the absence of the rs12506228 AA genotype. Because the risk allele has been connected to fewer brain MT1 melatonin receptors, these associations may reflect the influence of decreased melatonin signalling in early development.Peer reviewe

Prevalence and evolution of snoring and the associated factors in two-year-old children

AbstractObjectivesTo evaluate the prevalence and persistence of snoring during the first two years of life in two Finnish birth cohorts and to assess the associated factors.Study designThe study population comprised 947 children from the CHILD-SLEEP (CS) and 1393 children from the FinnBrain (FB) birth cohorts. Questionnaires were provided to both parents when the child was 24 months of age. The questionnaire consisted of parts concerning the child's sleep and environmental factors.ResultsThe combined prevalence of habitual snoring in the two birth cohorts at the age of 24 months was 2.3% (95% CI 1.5–3.1), which is markedly lower than reported previously.Children suffering from recurrent infections (CS odds ratio (OR) 3.9, 95% CI 1.2–12.5) or asthma (FB OR 4.3, 1.4–13.5) snored habitually more often. Both the mother's (CS OR 3.2, 1.2–9.0) and father's (CS OR 3.4, 1.4–8.0) snoring every night added to the risk of the child snoring. In the multivariate models, parental snoring (CS adjusted odds ratio (ORa) 2.8, 1.1–6.8), the mother's lower level of education (CS ORa 2.9, 1.2–7.5, FB ORa 2.1, 1.0–4.5), and the mother's lower monthly income (FB ORa 2.9, 1.3–6.3) associated with the child's habitual snoring.ConclusionsThe prevalence of habitual snoring in two Finnish birth cohorts is lower than reported previously. The independent risk factors for habitual snoring at the age of two years were the parents' snoring and the mother's low income and low education.</p

Visualization of toxin gene expression patterns in ribbon worm tissue sections by spatial transcriptomics

Ribbon worms (Nemertea) are active predators that use a proboscis to inject toxins into prey and defend themselves with toxic epidermal mucus. Nemerteans do not have distinct multi-cellular venom glands, instead toxins are secreted by cells lining the body wall and proboscis epithelia. The lack of a distinct gland has prevented the use of traditional venomics approaches to investigate their venom. Spatial Transcriptomics (ST) is a novel technology that allows to visualize and quantify transcriptomes within histological sections at 100 μm resolution. It facilitates the identification of toxins and their distribution within the tissue, revealing venom composition and producing tissue simultaneously. We adapted the method to analyze cryosections of 3 biological replicates from the species Cerebratulus marginatus, obtaining 3.5 million UMIs per replicate. After dimensionality reduction and clustering of RNA expression data, we identified 9 clusters linked to specific histological features. Proboscis and epidermis were the most distinct clusters, suggesting their profiles might be driven by toxin genes not expressed elsewhere. We mapped the expression data of mucus toxins such as nemertide alpha-1 and cytotoxin A-III on the tissue, revealing their distribution is not restricted to the epidermis. We also identified genes differentially expressed in the glandular epithelium of the proboscis, which may represent novel predatory toxins. Our findings suggest there is a hidden diversity of nemertean toxins and illustrate the capability of ST to investigate challenging venomous organisms, such as those without distinct venom glands or where venom cannot be milked.Peer reviewe