5,137 research outputs found
Maternal Pre-Pregnancy BMI, Gestational Weight Gain, And Infant Birth Weight: A Within-Family Analysis In The United States
In the United States, the high prevalence of unhealthy preconception body weight and inappropriate gestational weight gain among pregnant women is an important public health concern. However, the relationship among pre-pregnancy BMI, gestational weight gain, and newborn birth weight has not been well established. This study uses a very large dataset of sibling births and a within-family design to thoroughly address this issue. The baseline analysis controlling for mother fixed effects indicates maternal preconception overweight, preconception obesity, and excessive gestational weight gain significantly increase the risk of having a high birth weight baby, respectively, by 1.3, 3 and 3.9 percentage points, while underweight before pregnancy and inadequate gestational weight gain increase the low birth weight incidence by 1.4 and 2 percentage points. The benchmark results are robust in a variety of sensitivity checks. Since poor birth outcomes especially high birth weight and low birth weight have lasting adverse impacts on one’s health, education, and socio-economic outcomes later in life, the findings of this research suggest promoting healthy weight among women before pregnancy and preventing inappropriate weight gain during pregnancy can generate significant intergenerational benefits
Prenatal Smoking Cessation and Infant Health: Evidence from Sibling Births
This article uses a large data set of sibling births to examine when mothers must quit smoking in pregnancy to deliver healthy babies. It applies sibling fixed effects models to provide robust evidence that smoking cessation in the first trimester has a negligible effect on infant health, but cessation as late as second trimester or smoking throughout pregnancy is associated with substantially lower birth weights and higher risks of delivering low birth weight babies. In particular, about two thirds of the total detrimental smoking impact on birth outcomes occurs in the second trimester. Therefore, reallocating resources on prenatal smoking cessation towards the first trimester can lead to a significant efficiency gain. This study also shows when the timing information of prenatal smoking cessation is improperly used, it will introduce a new nontrivial downward bias in estimating the causality between the conventionally used group measure "prenatal smoker" and infant health
The Effects Of Prenatal Care Utilization On Maternal Health And Health Behaviors
While many economic studies have explored the role of prenatal care in infant health production, the literature is sporadic on the effects of prenatal care on the mother. This research contributes to this understudied but important area using a unique large dataset of sibling newborns delivered by 0.17 million mothers. We apply within-mother estimators to find robust evidence that poor prenatal care utilization due to late onset of care, low frequency of care visits, or combinations of the two significantly increases the risks of maternal insufficient gestational weight gain, prenatal smoking, premature rupture of membranes, precipitous labor, no breastfeeding, postnatal underweight, and postpartum smoking. The magnitude of the estimates relative to the respective sample means of the outcome variables ranges from 3% to 33%. The results highlight the importance of receiving timely and sufficient prenatal care in improving maternal health and health behaviors during pregnancy as well as after childbirth
Timing Of Prenatal Smoking Cessation Or Reduction And Infant Birth Weight: Evidence From The United Kingdom Millennium Cohort Study
Smoking during pregnancy is a key contributor to poor infant health. Our study presents a dynamic relationship between the timing of prenatal smoking cessation or reduction and infant birth weight. Using a large representative dataset of a birth cohort in the United Kingdom, we apply regression analysis to examine the influences of cessation in smoking or reduction in smoking intensity at different months or trimesters on infant birth weight. For robustness checks, we use a rich set of additional covariates, a series of variable selection procedures, alternative birth outcome measures, and stratified samples. We find robust evidence that mothers who quit smoking by the third month of pregnancy or the end of the first trimester have infants of the same weight as those infants of nonsmokers. However, we find smoking cessation in the fourth month or any time beyond is associated with substantially lower infant birth weights. Two-thirds of the total adverse smoking impact on infant birth weight occurs in the second trimester. Our study also shows mothers who smoke throughout pregnancy but cut smoking intensity by the third month in pregnancy deliver infants of the same weight as those infants born to persistent light smokers. Our research suggests the efficacy of prenatal smoking cessation services can be significantly improved, if health professionals can encourage more pregnant women to quit smoking or reduce smoking intensity timely by the end of the first trimester
Carbon nanodots (CNDs): tuning structures and functions in oxidative radical interactions
Carbon nanodots (CNDs), reported as polyatomic carbon domains surrounded by amorphous carbon frames, have drawn extensive attention due to their easy-to-synthesis, outstanding optoelectronic properties, and superior biocompatibility. Moreover, CNDs have shown good antioxidant capabilities by scavenging free radicals such as diphenyl-1-picrylhydrazyl radical (DPPH•) and reactive oxygen species (ROS). While some studies suggest that the antioxidation activities associate to the proton donor role of surface-active groups like carboxyl groups (-COOH), it is unclear how the functional groups or composites on CNDs’ surfaces affect the antioxidation of CNDs. Meanwhile, limited assessments on the biological effects of CNDs, particularly the effect on oxidative stress in living cells, have restricted their further development. To address this issue, we propose to tune CNDs’ structures and examine the interactions between the oxidative radicals and the CNDs. In this work, we have 1) modified the surface functional groups of CNDs, specifically the -COOH and -NH2 groups, to investigate the interactions with DPPH• in chemistry, and 2) doped additional elements (e.g. nitrogen and/or sulfur) to change the composites/structures of CNDs and study their interactions with oxidative radicals in vitro. The results demonstrate that both the carboxyl and the amino groups contribute to the antioxidation activity of CNDs through either a direct or indirect hydrogen atom transfer reaction with DPPH•. In addition, the nitrogen doped CNDs (N-CNDs) exhibited excellent biocompatibility and antioxidation capability in two cell lines, EA.hy926 (normal cells) and A549 (lung cancer cells). Whereas, relatively high doses treatment of the nitrogen sulfur doped CNDs (N,S-CNDs) cause in vitro cytotoxicity by stimulating more generation of intracellular ROS in the two cell lines. Further intracellular studies indicate that both the N-CNDs and N,S-CNDs mostly are localized at the mitochondria of the cells. These results suggest that the CNDs may regulate the electron transport chain in mitochondria for ROS generation, and the sulfur element and associated functional groups in the CNDs play a key role for the ROS generation. In summary, the findings in this dissertation work presents some advances in knowledge of structure-functions of CNDs for radical scavenging, intracellular process and oxidative stress effect in living cells, which may accelerate the practical development in the field of biomedicine. [This abstract has been edited to remove characters that will not display in this system. Please see the PDF for the full abstract.]]]>
2020
Nanostructured materials
Biocompatibility
Antioxidants
English
http://libres.uncg.edu/ir/uncg/f/Ji_uncg_0154D_12974.pdf
oai:libres.uncg.edu/32999
2020-08-14T10:20:41Z
UNCG
Developmental patterns of respiratory sinus arrhythmia from toddlerhood to adolescence
Calkins, Susan D.
Dollar, Jessica
Keane, Susan P.
NC DOCKS at The University of North Carolina at Greensboro
Wideman, Laurie
<![CDATA[Parasympathetic nervous system functioning as indexed by respiratory sinus arrhythmia (RSA) is widely used as a measure of physiological regulation. We examined developmental patterns of children’s resting RSA and RSA reactivity from 2 to 15 years of age, a period of time that is marked by considerable advances in children’s regulatory abilities. Physiological data were collected from a community sample of 270 children (116 males) during a resting period and during a frustration laboratory task when the children were 2, 4, 5, 7, 10, and 15 years old. We examined both stability and continuity in resting RSA and RSA reactivity across time. We found stability in resting RSA but not RSA reactivity from toddlerhood to adolescence. Separate multilevel models were used to examine changes in resting RSA and RSA reactivity from Age 2 to Age 15. The rate of change in resting RSA slowed from Age 2 to Age 15 with a plateau around Age 10. A splined growth model indicated that the rate of RSA reactivity increased from Age 2 to Age 7 and a modest slowing and leveling off from Age 7 to Age 15. Understanding the developmental characteristics of RSA across childhood and adolescence is important to understanding the larger constructs of self- and emotion regulation
Personality styles in patients with fibromyalgia, major depression and healthy controls
BACKGROUND: The fibromyalgia syndrome (FMS) is suggested to be a manifestation of depression or affective spectrum disorder. We measured the cognitive style of patients with FMS to assess personality styles in 44 patients with fibromyalgia syndrome (FMS) by comparing them with 43 patients with major depressive disorder (MDD) and 41 healthy controls (HC). METHODS: Personality styles were measured by the Sociotropy and Autonomy Scale (SAS) and the Dysfunctional Attitude Scale (DAS). The Structured Clinical interview for DSM Axis I was applied to Axis I disorders, while the Beck Depression Inventory was used to measure depression severity. RESULTS: Patients with FMS in general have a sociotropic personality style similar to patients with MDD, and different from HC, but FMS patients without a lifetime history of MDD had a cognitive personality style different from patients with MDD and similar to HC. CONCLUSION: These findings suggest that a depressotypic personality style is related to depressive disorder, but not to FMS
Phylogeny of Basal Iguanodonts (Dinosauria: Ornithischia): An Update
The precise phylogenetic relationships of many non-hadrosaurid members of Iguanodontia, i.e., basal iguanodonts, have been unclear. Therefore, to investigate the global phylogeny of basal iguanodonts a comprehensive data matrix was assembled, including nearly every valid taxon of basal iguanodont. The matrix was analyzed in the program TNT, and the maximum agreement subtree of the resulting most parsimonious trees was then calculated in PAUP. Ordering certain multistate characters and omitting taxa through safe taxonomic reduction did not markedly improve resolution. The results provide some new information on the phylogeny of basal iguanodonts, pertaining especially to obscure or recently described taxa, and support some recent taxonomic revisions, such as the splitting of traditional “Camptosaurus” and “Iguanodon”. The maximum agreement subtree also shows a close relationship between the Asian Probactrosaurus gobiensis and the North American Eolambia, supporting the previous hypothesis of faunal interchange between Asia and North America in the early Late Cretaceous. Nevertheless, the phylogenetic relationships of many basal iguanodonts remain ambiguous due to the high number of taxa removed from the maximum agreement subtree and poor resolution of consensus trees
Optical Trapping of an Ion
For several decades, ions have been trapped by radio frequency (RF) and
neutral particles by optical fields. We implement the experimental
proof-of-principle for trapping an ion in an optical dipole trap. While
loading, initialization and final detection are performed in a RF trap, in
between, this RF trap is completely disabled and substituted by the optical
trap. The measured lifetime of milliseconds allows for hundreds of oscillations
within the optical potential. It is mainly limited by heating due to photon
scattering. In future experiments the lifetime may be increased by further
detuning the laser and cooling the ion. We demonstrate the prerequisite to
merge both trapping techniques in hybrid setups to the point of trapping ions
and atoms in the same optical potential.Comment: 5 pages, 3 figure
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