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Selection medium is important in sperm isolation for assisted reproductive technologies. Contrary to the naturally occurring human cervical mucus which has a high viscosity, most current practices for motility based sperm selection use a low viscosity medium. In this study, we used a microfluidic device to assess the effects of high viscosity media made with hyaluronic acid (HA) and methyl cellulose (MC) on bovine and human sperm motility and viability (sperm transferred directly from cryoprotectant). The microfluidic penetration test, viability, and motility were compared for sperm swimming in both HA and MC media with about 20cp viscosity (measured at 20 °C). Our resulted indicate that MC medium resulted in a significantly higher number of viable bovine sperm penetrating the medium as compared to HA. Furthermore, MC resulted in the selection of a sperm subpopulation with a 274% increase in sperm viability in comparison to the raw semen, while HA increased viability by only 133%. In addition to viability, bovine sperm motility parameters were significantly higher in the MC medium as compared with HA. Experiments with human sperm swimming in MC indicate that sperm swim slower and straighter at higher viscosities. In conclusion, the results indicate that in a micro-confined environment representative of the in vivo environment, MC is a preferred high viscosity medium to ensure the highest concentration of motile and viable sperm. 相似文献
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Infant Attachment Security and Early Childhood Behavioral Inhibition Interact to Predict Adolescent Social Anxiety Symptoms
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Erin Lewis‐Morrarty Kathryn A. Degnan Andrea Chronis‐Tuscano Daniel S. Pine Heather A. Henderson Nathan A. Fox 《Child development》2015,86(2):598-613
Insecure attachment and behavioral inhibition (BI) increase risk for internalizing problems, but few longitudinal studies have examined their interaction in predicting adolescent anxiety. This study included 165 adolescents (ages 14–17 years) selected based on their reactivity to novelty at 4 months. Infant attachment was assessed with the Strange Situation. Multimethod BI assessments were conducted across childhood. Adolescents and their parents independently reported on anxiety. The interaction of attachment and BI significantly predicted adolescent anxiety symptoms, such that BI and anxiety were only associated among adolescents with histories of insecure attachment. Exploratory analyses revealed that this effect was driven by insecure‐resistant attachment and that the association between BI and social anxiety was significant only for insecure males. Clinical implications are discussed. 相似文献
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Öberg Gunilla Campbell Alice Fox Joanne Graves Marcia Ivanochko Tara Matsuchi Linda Mouat Isobel Welsh Ashley 《Science & Education》2022,31(3):787-817
Science & Education - The widespread misperception of science as a deliverer of irrefutable facts, rather than a deliberative process, is undermining public trust in science. Science education... 相似文献
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Kyle S. Wiley Molly M. Fox Theresa E. Gildner Zaneta M. Thayer 《Child development》2023,94(5):1356-1367
Infant social–emotional development may be impacted by the COVID-19 pandemic. This study investigated associations between maternal pre- and postnatal pandemic-related concerns and social–emotional developmental risk. Data, collected in 2020–2021, came from 220 mothers (87% white, 6% Hispanic, 1% Black, 3% Asian, 1% American Indian, Mage = 32.46 years), and infants (53.18% male, Mage = 12.98 months) in the United States. Maternal postnatal pandemic-related concerns were associated with total risk scores (B = 6.09, p-value <.001) and offspring risk of scoring positive for problems related to inflexibility (B = 4.07, p-value = .006). The total score association was moderated by self-reported social support. Infants may be detrimentally impacted by the pandemic via maternal pandemic-related concerns. Maternal social support may buffer infants. 相似文献
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The authors explored the relationship between counseling trainees' emotional intelligence (EI), empathy, stress, distress, and demographics. Results indicated that higher levels of EI were associated with lower stress and distress, higher affective and cognitive empathy, and age. These findings suggest curricular integration of EI and potential utility of EI measures to evaluate students' progress throughout the program. 相似文献
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Windsor J Benigno JP Wing CA Carroll PJ Koga SF Nelson CA Fox NA Zeanah CH 《Child development》2011,82(4):1040-1046
This report examines 174 young children's language outcomes in the Bucharest Early Intervention Project, the first randomized trial of foster placement after institutional care. Age of foster placement was highly correlated with language outcomes. Placement by 15 months led to similar expressive and receptive language test scores as typical age peers at 30 and 42 months. Placement from 15 to 24 months also led to dramatic language improvement. In contrast, children placed after 24 months had the same severe language delays as children in institutional care. Language samples at 42 months confirmed that placement after 24 months led to lower expressive skill. 相似文献
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Charles H. Zeanah Megan R. Gunnar Robert B. McCall Jana M. Kreppner Nathan A. Fox 《Monographs of the Society for Research in Child Development》2011,76(4):147-162
This chapter reviews sensitive periods in human brain development based on the literature on children raised in institutions. Sensitive experiences occur when experiences are uniquely influential for the development of neural circuitry. Because in humans, we make inferences about sensitive periods from evaluations of complex behaviors, we underestimate the occurrence of sensitive periods at the level of neural circuitry. Although we are most interested in complex behaviors, such as IQ or attachment or externalizing problems, many different sensitive periods at the level of circuits probably underlie these complex behaviors. Results from a number of studies suggest that across most, but not all, domains of development, institutional rearing limited to the first 4–6 months of life is associated with no significant increase risk for long‐term adverse effects relative to noninstitutionalized children. Beyond that, evidence for sensitive periods is less compelling, meaning that “the earlier the better” rule for enhanced caregiving is a reasonable conclusion at the current state of the science. 相似文献