Social Determinants of Health and Adverse Outcomes in Adolescent Pregnancies.

The association between adolescent childbearing and adverse maternal and birth outcomes has been well documented. Adverse adolescent pregnancy outcomes are associated with substantial risk of long-term morbidities for the young mother and their newborns. Multiple levels of social disadvantage have been related to adverse pregnancy outcomes among adolescent mothers. Patterns of cumulative social adversity define the most marginalized group of adolescents at the highest risk of experiencing adverse maternal and birth outcomes. Using a social determinants of health (SDOH) framework, we present an overview of the current scientific evidence on the influence of these conditions on adolescent pregnancy outcomes. Multiple SDOH such as residence in remote areas, low educational attainment, low socioeconomic status, and lack of family and community support have been linked with increased risk of adverse pregnancy outcomes among adolescents. Based on the PROGRESS-Plus equity framework, this review highlights some SDOH aspects that perinatal health researchers, clinicians, and policy makers should consider in the context of adolescent pregnancies. There is a need to acknowledge the intersectional nature of multiple SDOH when formulating clinical and societal interventions to address the needs of the most marginalized adolescent in this critical period of life.

Heterogeneous mass distribution of the rubble-pile asteroid (101955) Bennu.

The gravity field of a small body provides insight into its internal mass distribution. We used two approaches to measure the gravity field of the rubble-pile asteroid (101955) Bennu: (i) tracking and modeling the spacecraft in orbit about the asteroid and (ii) tracking and modeling pebble-sized particles naturally ejected from Bennu's surface into sustained orbits. These approaches yield statistically consistent results up to degree and order 3, with the particle-based field being statistically significant up to degree and order 9. Comparisons with a constant-density shape model show that Bennu has a heterogeneous mass distribution. These deviations can be modeled with lower densities at Bennu's equatorial bulge and center. The lower-density equator is consistent with recent migration and redistribution of material. The lower-density center is consistent with a past period of rapid rotation, either from a previous Yarkovsky-O'Keefe-Radzievskii-Paddack cycle or arising during Bennu's accretion following the disruption of its parent body.

Hemispherical differences in the shape and topography of asteroid (101955) Bennu.

We investigate the shape of near-Earth asteroid (101955) Bennu by constructing a high-resolution (20 cm) global digital terrain model from laser altimeter data. By modeling the northern and southern hemispheres separately, we find that longitudinal ridges previously identified in the north extend into the south but are obscured there by surface material. In the south, more numerous large boulders effectively retain surface materials and imply a higher average strength at depth to support them. The north has fewer large boulders and more evidence of boulder dynamics (toppling and downslope movement) and surface flow. These factors result in Bennu's southern hemisphere being rounder and smoother, whereas its northern hemisphere has higher slopes and a less regular shape. We infer an originally asymmetric distribution of large boulders followed by a partial disruption, leading to wedge formation in Bennu's history.

Bright carbonate veins on asteroid (101955) Bennu: Implications for aqueous alteration history.

The composition of asteroids and their connection to meteorites provide insight into geologic processes that occurred in the early Solar System. We present spectra of the Nightingale crater region on near-Earth asteroid Bennu with a distinct infrared absorption around 3.4 micrometers. Corresponding images of boulders show centimeters-thick, roughly meter-long bright veins. We interpret the veins as being composed of carbonates, similar to those found in aqueously altered carbonaceous chondrite meteorites. If the veins on Bennu are carbonates, fluid flow and hydrothermal deposition on Bennu's parent body would have occurred on kilometer scales for thousands to millions of years. This suggests large-scale, open-system hydrothermal alteration of carbonaceous asteroids in the early Solar System.

Shape of (101955) Bennu indicative of a rubble pile with internal stiffness.

The shapes of asteroids reflect interplay between their interior properties and the processes responsible for their formation and evolution as they journey through the Solar System. Prior to the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) mission, Earth-based radar imaging gave an overview of (101955) Bennu's shape. Here, we construct a high-resolution shape model from OSIRIS-REx images. We find that Bennu's top-like shape, considerable macroporosity, and prominent surface boulders suggest that it is a rubble pile. High-standing, north-south ridges that extend from pole to pole, many long grooves, and surface mass wasting indicate some low levels of internal friction and/or cohesion. Our shape model indicates that, similar to other top-shaped asteroids, Bennu formed by reaccumulation and underwent past periods of fast spin leading to its current shape. Today, Bennu might follow a different evolutionary pathway, with interior stiffness permitting surface cracking and mass wasting.

The dynamic geophysical environment of (101955) Bennu based on OSIRIS-REx measurements.

The top-shape morphology of asteroid (101955) Bennu is commonly found among fast-spinning asteroids and binary asteroid primaries, and might have contributed significantly to binary asteroid formation. Yet a detailed geophysical analysis of this morphology for a fast-spinning asteroid has not been possible prior to the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission. Combining the measured Bennu mass and shape obtained during the Preliminary Survey phase of OSIRIS-REx, we find a significant transition in Bennu's surface slopes within its rotational Roche lobe, defined as the region where material is energetically trapped to the surface. As the intersection of the rotational Roche lobe with Bennu's surface has been most recently migrating towards its equator (given Bennu's increasing spin rate), we infer that Bennu's surface slopes have been changing across its surface within the last million years. We also find evidence for substantial density heterogeneity within this body, suggesting that its interior has a distribution of voids and boulders. The presence of such heterogeneity and Bennu's top-shape is consistent with spin-induced failure at some point in its past, although the manner of its failure cannot be determined yet. Future measurements by the OSIRIS-REx spacecraft will give additional insights and may resolve questions regarding the formation and evolution of Bennu's top-shape morphology and its link to the formation of binary asteroids.

Predictors of drug use during pregnancy: The relative effects of socioeconomic, demographic, and mental health risk factors.

BACKGROUND: With limited Canadian research on predictors of drug use during pregnancy, the primary objective was to assess the relative effects of socioeconomic, demographic, and mental health risk factors associated with drug use during pregnancy. Predictors of an Apgar score < 7 and fetal macrosomia were examined as secondary outcomes. METHODS: This retrospective cohort study consisted of 25,734 pregnant women from Southwestern Ontario. Data were prospectively obtained from perinatal and neonatal databases at a tertiary hospital in London, Ontario. Using a Geographic Information System, neighborhood-level socioeconomic variables were obtained by mapping maternal postal codes. Separate logistic regressions were computed for all outcome variables. RESULTS: The rates of alcohol, tobacco, and cannabis use during pregnancy were 1.9%, 16.2%, and 2.3%, respectively. The mean maternal age was 29.4±5.4 years. Maternal age was inversely associated with alcohol, tobacco and cannabis use, whereas lone-parent household, depression, and anxiety increased the odds of substance use. Depression was the top risk factor of all three substances. Compared to women who were not depressed during pregnancy, women who were depressed were 2.15 times more likely to use alcohol (95% CI: 1.60, 2.90), 1.70 times more likely to smoke tobacco (95% CI: 1.48, 1.95), and 2.56 times more likely to use cannabis (95% CI: 1.95, 3.35). Adverse birth outcomes were also associated with overweight and obesity, gestational diabetes and insulin-dependent diabetes. CONCLUSIONS: Maternal depression is the primary risk factor of drug use during pregnancy. Policy interventions that target at-risk women are important considerations to improve maternal mental health.

Is Breast Best? Examining the effects of alcohol and cannabis use during lactation.

Maternal drug use during lactation may have adverse effects on the health of their children. Two common drugs used during this period are alcohol and cannabis. A literature search was conducted using PubMed, CINAHL, Nursing and Allied Health, and Google Scholar with the following search terms: marijuana, cannabis, THC, alcohol, ethanol, breastfeeding, lactation, and breastmilk. The search strategy was restricted to papers since the year 2000, and limited to English language journals. Reference lists were also used to capture any articles that were missed from the database searches. In total, 19 articles were found related to alcohol and breastfeeding (n = 17 original research papers; n = 2 systematic reviews), and 4 articles were specific to cannabis (n = 2 original papers; n = 2 systematic reviews). The most common outcomes associated with alcohol consumption and breastfeeding included changes in sleep patterns, reduced milk production and flow, lower milk intake, and impaired immune function. Maternal outcomes related to cannabis consumption included panic attacks, delayed response time, increased heart rate, reduced short-term memory, dizziness, and impaired motor performance; infant outcomes associated with maternal cannabis use and breastfeeding were reduced muscular tonus, poor sucking, and growth delay and restriction. Mothers should be advised to refrain from substance use during the lactation period for the health and safety of their children.

The perception of pre- and post-natal marijuana exposure on health outcomes: A content analysis of Twitter messages.

The prevalence of marijuana use during pregnancy ranges from 3-30% , and most of this is for recreational purposes. Marijuana exposure during pregnancy has been linked with low birth weight babies and other adverse child health outcomes. Twitter is a popular news and social networking outlet, and is frequently used to access information about population health and behavior. The primary objective of this study was to investigate the types of messages disseminated on Twitter about marijuana use and infant and maternal health. The secondary objective was to describe the reported health outcomes associated with prenatal and postnatal marijuana use. Tweets were collected from the inception of Twitter (2006) until April 2017. If tweets included links, these links were examined to investigate the source of the message and to clarify the user's intent. In total, 550 tweets were captured, with most tweets (77.6%) having a neutral tweet tone, suggesting uncertainty about the health effects associated with pre- and post-natal marijuana exposure. The sources attached to the original tweets, however, were more likely to report on negative health outcomes. The most common health outcomes associated with prenatal marijuana exposure were: poor brain development (27.3%), inadequate development of the nervous system (23.6%), low birth weight (23.3%), poor behavioral outcomes (21.0%), and infant memory issues (19.3%). The inverse association between marijuana use and the quality and quantity of milk produced by the mother was the most commonly reported tweet for the lactation period.

The association between alcohol outlet accessibility and adverse birth outcomes: A retrospective cohort study.

BACKGROUND: Alcohol outlet accessibility is positively associated with alcohol consumption, although this relationship has not been thoroughly examined in pregnant women. The present study examines the relationship between proximity and density of alcohol outlets and risk for low birth weight (LBW: <2,500 grams) and preterm birth (PTB: <37 weeks gestational age), and is the first Canadian study to investigate this association. METHODS: Maternal accessibility to alcohol outlets was specified using a gravity-type measure of accessibility, which provides the amount of accessibility that a given household has to liquor stores within 30-minutes of their home. All singleton newborns without congenital anomalies that were born between February 2009 and February 2014 at London Health Sciences Centre in London, Ontario, were included in this cohort. RESULTS: The sample consisted of 25,734 live births, of which 5.8% were LBW and 7.6% were PTB. Only 2.0% of women reported alcohol use during pregnancy. Alcohol outlet gravity was positively correlated with the percentage of mothers living in poverty (rs = 0.33, p < 0.001) and in single-parent families (rs = 0.39, p < 0.001), and who self-identify as visible minorities (rs = 0.45, p < 0.001). Alcohol outlet gravity increased the odds that mothers drank alcohol during pregnancy (OR 1.05; 95% CI: 1.02, 1.07), although the association was weak. Furthermore, alcohol outlet gravity did not increase the likelihood of a LBW or PTB infant. CONCLUSIONS: Women with high accessibility to alcohol outlets are more likely to consume alcohol during pregnancy, but greater alcohol outlet accessibility does not translate into poor birth outcomes.

The influence of the built environment on adverse birth outcomes.

Adverse birth outcomes are associated with neonatal morbidity and mortality, and higher risk for coronary heart disease, non-insulin-dependent diabetes and hypertension in adulthood. Although there has been considerable research investigating the association between maternal and environmental factors on adverse birth outcomes, one risk factor, not fully understood, is the influence of the built environment. A search of MEDLINE, Scopus, and Cochrane was conducted to find articles assessing the influence of the built environment on preterm birth (PTB), low birth weight (LBW), and small-for-gestational-age (SGA). In total, 41 studies met our inclusion criteria, and were organized into nine categories: Roadways, Greenness, Power Plants, Gas Stations/Wells, Waste Management, Power Lines, Neighborhood Conditions, Food Environment, and Industry. The most common built environmental variable was roads/traffic, encompassing 17/41 (41%) of the articles reviewed, of which 12/17 (71%) found a significant small to moderate association between high traffic exposure and adverse birth outcomes.

Cervical spine injuries and collar complications in severely injured paediatric trauma patients.

STUDY DESIGN: A retrospective registry review. OBJECTIVES: To determine the incidence of cervical spine (CS) injuries and collar complications in severely injured paediatric trauma patients. SETTING: Regional Trauma Centre, Children's Hospital. METHODS: A retrospective review of 365 paediatric severe trauma patients (0-17 years), defined as an Injury Severity Score (ISS)≥12, admitted to the paediatric intensive care unit (PICU). RESULTS: Clinically significant CS injuries occurred in 5% (n=18/365) of trauma patients, in 9% (n=13/149) of traumatic brain injury (TBI) patients and in 11% (n=6/56) of in-hospital trauma deaths. CS injuries were suspected before imaging in 33% (n=6/18) of patients based on either motor/sensory impairment or shock. CS injuries were deemed unstable in 61% (n=11/18) of patients. Patients with CS injuries had higher ISS, and longer PICU and hospital stays (P<0.05). CS collar complications occurred in 10% of patients, mainly identified by day 6 and consisting of either erythema or ulcers. Patients with CS collar complications were older and more likely to have TBI, lower Glasgow Coma Scale (GCS) scores, longer PICU and hospital stays, and increased days to CS clearance (P<0.05). Three CS X-rays, together with flexion/extension views, were used most frequently for CS clearance. CONCLUSION: CS injuries were prevalent in severely injured paediatric trauma patients, particularly in those with TBI and in nonsurvivors. CS collar complications were associated with a lower GCS and longer CS clearance times. Attention to CS collar management protocols and earlier CS clearance with computed tomography/magnetic resonance imaging in obtunded patients might reduce CS collar complications.

Mars water-ice clouds and precipitation.

The light detection and ranging instrument on the Phoenix mission observed water-ice clouds in the atmosphere of Mars that were similar to cirrus clouds on Earth. Fall streaks in the cloud structure traced the precipitation of ice crystals toward the ground. Measurements of atmospheric dust indicated that the planetary boundary layer (PBL) on Mars was well mixed, up to heights of around 4 kilometers, by the summer daytime turbulence and convection. The water-ice clouds were detected at the top of the PBL and near the ground each night in late summer after the air temperature started decreasing. The interpretation is that water vapor mixed upward by daytime turbulence and convection forms ice crystal clouds at night that precipitate back toward the surface.

Agnathia (severe micrognathia), aglossia and choanal atresia in an infant.

A neonate is reported here, who was born with severe mandibular hypoplasia, complete absence of the tongue, unilateral choanal atresia, contralateral choanal stenosis and developed severe airway obstruction at birth. Arrested development of the ventral first branchial arch most likely underlies the clinical deficits. Most reported cases of agnathia have been lethal but the infant reported here has survived into infancy with a tracheostomy and feeding gastrostomy. Her clinical features, assessment and management are discussed.

The vascular interaction of noradrenaline and 5-hydroxytryptamine.

The action of 5-hydroxytryptamine (5-HT) to potentiate vasoconstrictor responses to noradrenaline has been studied using the rat isolated perfused mesenteric artery. Receptor antagonists have been employed to compare the vascular receptors which mediate the vasoconstrictor and potentiating actions of 5-HT. In preparations pretreated with methysergide (1 mumol X 1(-1)), cyproheptadine (1 mumol X 1(-1)) or fluoxetine (1 mumol X 1(-1)) the vasoconstrictor response to 5-HT (1 mumol X 1(-1)) was abolished, while ketanserin (1 nmol X 1(-1)) antagonized the response by 90%. In contrast, only methysergide antagonized the sensitizing effect of 5-HT, while the other three antagonists exerted no effect on this action. In view of the different sensitivities of the vasoconstrictor and potentiating effects of 5-HT to antagonist drugs, it is suggested that the vascular receptors which mediate these actions are different.

The in vitro propagation of amaryllis (Hippeastrum spp. hybrids).

A new, rapid technique for the propagation of amaryllis (Hippeastrum spp. hybrids) by means of tissue culture is reported. Leaf bases, scapes, peduncles, inner bulb scales and ovaries were cultured successfully in vitro and plantlets were induced readily at various concentrations of growth regulators. Some plantlets also were produced in the absence of growth regulators. The most productive tissues for propagation were inverted scapes and peduncles, cultured in a modified Murashige and Skoog salt solution with added organic constituents and 1 mg per 1 (4.5 micron) 2,4-dichlorophenoxyacetic acid (2,4-D) and 1 mg per 1 (4.4 micrometer) 6-benzylaminopurine (BAP). Plantlets induced axenically also grew roots on the generalized shoot-inducing medium so that no special rooting medium was required. Although friable callus was obtained from ovary tissue cultured on a medium containing 2 mg per 1 (11 micrometer) naphthaleneacetic acid and 4 mg per 1 (18 micrometer) BAP, it produced shoots after 8 weeks of further subculture on the same medium. An average of 10 rooted plantlets was obtained from each scape or peduncle explant on the shoot-propagating medium. Thus, if 45 explants are obtained from each bulb, 450 rudimentary plantlets could be obtained from each mother bulb in 8 weeks of culture. This is a substantial increase over present propagation methods.