Territorial scent-marking effects on vigilance behavior, space use, and stress in female Columbian ground squirrels.

Social environments can profoundly affect the behavior and stress physiology of group-living animals. In many territorial species, territory owners advertise territorial boundaries to conspecifics by scent marking. Several studies have investigated the information that scent marks convey about donors' characteristics (e.g., dominance, age, sex, reproductive status), but less is known about whether scents affect the behavior and stress of recipients. We experimentally tested the hypothesis that scent marking may be a potent source of social stress in territorial species. We tested this hypothesis for Columbian ground squirrels (Urocitellus columbianus) during lactation, when territorial females defend individual nest-burrows against conspecifics. We exposed lactating females, on their territory, to the scent of other lactating females. Scents were either from unfamiliar females, kin relatives (a mother, daughter, or sister), or their own scent (control condition). We expected females to react strongly to novel scents from other females on their territory, displaying increased vigilance, and higher cortisol levels, indicative of behavioral and physiological stress. We further expected females to be more sensitive to unfamiliar female scents than to kin scents, given the matrilineal social structure of this species and known fitness benefits of co-breeding in female kin groups. Females were highly sensitive to intruder (both unfamiliar and kin) scents, but not to their own scent. Surprisingly, females reacted more strongly to the scent of close kin than to the scent of unfamiliar females. Vigilance behavior increased sharply in the presence of scents; this increase was more marked for kin than unfamiliar female scents, and was mirrored by a marked 131% increase in free plasma cortisol levels in the presence of kin (but not unfamiliar female) scents. Among kin scents, lactating females were more vigilant to the scent of sisters of equal age, but showed a marked 318% increase in plasma free cortisol levels in response to the scent of older and more dominant mothers. These results suggest that scent marks convey detailed information on the identity of intruders, directly affecting the stress axis of territory holders.

Telomere dynamics in female Columbian ground squirrels: recovery after emergence and loss after reproduction.

Telomeres are specialized non-coding DNA sequences located at the end of chromosomes and that protect genetic information. Telomere loss over lifespan is generally viewed as a phenomenon associated with aging in animals. Recently, telomere elongation after hibernation has been described in several mammals. Whether this pattern is an adaptation to repair DNA damage caused during rewarming from torpor or if it coevolved as a mechanism to promote somatic maintenance in preparation for the upcoming reproductive effort remains unclear. In a longitudinal study measuring telomere length using buccal swabs, we tested if telomere elongation was related to reproductive success in wild adult female Columbian ground squirrels (Urocitellus columbianus) that were monitored from emergence from hibernation to the end of the reproductive season. We found three key results. First, female telomere length increased at the start of the breeding season, both in breeding and non-breeding individuals. Second, post-emergence telomere lengthening was unrelated to female future reproductive output. Third, telomere length decreased in breeding females during lactation, but remained stable in non-breeding females over a similar period. Within breeders, telomeres shortened more in females producing larger and heavier litters. We concluded that telomere lengthening after hibernation did not constrain immediate female reproductive capacities. It was more likely to be part of the body recovery process that takes place after hibernation. Telomere erosion that occurs after birth may constitute a physiological cost of female reproduction.

Socioeconomic status and genetic influences on cognitive development.

Accurate understanding of environmental moderation of genetic influences is vital to advancing the science of cognitive development as well as for designing interventions. One widely reported idea is increasing genetic influence on cognition for children raised in higher socioeconomic status (SES) families, including recent proposals that the pattern is a particularly US phenomenon. We used matched birth and school records from Florida siblings and twins born in 1994-2002 to provide the largest, most population-diverse consideration of this hypothesis to date. We found no evidence of SES moderation of genetic influence on test scores, suggesting that articulating gene-environment interactions for cognition is more complex and elusive than previously supposed.

Small-for-Gestational Age Birth Confers Similar Educational Performance through Middle School.

OBJECTIVE: To estimate the association between small for gestational age (SGA) at birth and educational performance on standardized testing and disability prevalence in elementary and middle school. STUDY DESIGN: Through linked birth certificates and school records, surviving infants born at 23-41 weeks of gestation who entered Florida's public schools 1998-2009 were identified. Twenty-three SGA definitions (3rd-25th percentile) were derived. Outcomes were scores on Florida Comprehensive Assessment Test (FCAT) and students' disability classification in grades 3 through 8. A "sibling cohort" subsample included families with at least 2 siblings from the same mother in the study period. Multivariable models estimated independent relationships between SGA and outcomes. RESULTS: Birth certificates for 80.2% of singleton infants were matched to Florida public school records (N = 1 254 390). Unadjusted mean FCAT scores were 0.236 SD lower among <10th percentile SGA infants compared with non-SGA infants; this difference declined to -0.086 SD after adjusting for maternal and infant characteristics. When siblings discordant in SGA status were compared within individual families, the association declined to -0.056 SD. For SGA <10th percentile infants, the observed prevalence of school-age disability was 15.0%, 7.7%, and 6.3% for unadjusted, demographics-adjusted, and sibling analyses, respectively. No inflection or discontinuity was detected across SGA definitions from 3rd to 25th percentile in either outcome, and the associations were qualitatively similar. CONCLUSIONS: The associations between SGA birth and students' standardized test scores and well-being were quantitatively small but persisted through elementary and middle school. The observed deficits were largely mitigated by demographic and familial factors.

Subtle short-term physiological costs of an experimental augmentation of fleas in wild Columbian ground squirrels.

Parasites affect many aspects of host physiology and behavior, and thus are generally thought to negatively impact host fitness. However, changes in form of short-term parasite effects on host physiological markers have generally been overlooked in favor of fitness measures. Here, we studied flea (Oropsylla idahoensis and Oropsylla opisocroistis tuberculata) parasitism on a natural population of Columbian ground squirrels (Urocitellus columbianus) in Sheep River Provincial Park, AB, Canada. Fleas were experimentally added to adult female U. columbianus at physiologically demanding times, including birth, lactation and weaning of their young. The body mass of adult females, as well as their oxidative stress and immunity were recorded multiple times over the active season under flea-augmented and control conditions. We also measured the prevalence of an internal parasite (Trypanosoma otospermophili). Doubly labeled water (DLW) was intra-peritoneally injected at peak lactation to examine energy expenditure. Effects of parasites on oxidative stress were only observed after offspring were weaned. There was no direct effect of experimentally heightened flea prevalence on energy use. A short-term 24 h mass loss (-17 g) was detected briefly after parasite addition, likely due to U. columbianus preferentially allocating time for grooming. Our parasite augmentation did not strongly affect hosts and suggested that short-term physiological effects were unlikely to culminate in long-term fitness consequences. Columbian ground squirrels appear to rapidly manage parasite costs, probably through grooming.

Combining adverse pregnancy and perinatal outcomes for women exposed to antiepileptic drugs during pregnancy, using a latent trait model.

BACKGROUND: Application of latent variable models in medical research are becoming increasingly popular. A latent trait model is developed to combine rare birth defect outcomes in an index of infant morbidity. METHODS: This study employed four statewide, retrospective 10-year data sources (1999 to 2009). The study cohort consisted of all female Florida Medicaid enrollees who delivered a live singleton infant during study period. Drug exposure was defined as any exposure to Antiepileptic drugs (AEDs) during pregnancy. Mothers with no AED exposure served as the AED unexposed group for comparison. Four adverse outcomes, birth defect (BD), abnormal condition of new born (ACNB), low birth weight (LBW), and pregnancy and obstetrical complication (PCOC), were examined and combined using a latent trait model to generate an overall severity index. Unidimentionality, local independence, internal homogeneity, and construct validity were evaluated for the combined outcome. RESULTS: The study cohort consisted of 3183 mother-infant pairs in total AED group, 226 in the valproate only subgroup, and 43,956 in the AED unexposed group. Compared to AED unexposed group, the rate of BD was higher in both the total AED group (12.8% vs. 10.5%, P < .0001), and the valproate only subgroup (19.6% vs. 10.5%, P < .0001). The combined outcome was significantly correlated with the length of hospital stay during delivery in both the total AED group (Rho = 0.24, P < .0001) and the valproate only subgroup (Rho = 0.16, P = .01). The mean score for the combined outcome in the total AED group was significantly higher (2.04 ± 0.02 vs. 1.88 ± 0.01, P < .0001) than AED unexposed group, whereas the valproate only subgroup was not. CONCLUSIONS: Latent trait modeling can be an effective tool for combining adverse pregnancy and perinatal outcomes to assess prenatal exposure to AED, but evaluation of the selected components is essential to ensure the validity of the combined outcome.

Associations Between Residential Proximity to Power Plants and Adverse Birth Outcomes.

Few studies have assessed the associations between residential proximity to power plants and adverse birth outcomes including preterm delivery (PTD), very preterm delivery (VPTD), and term low birth weight (LBW). We geocoded 423,719 singleton Florida births born from 2004 to 2005 and all active power plants and determined residential proximity to the nearest power plant for each birth. Prenatal exposure to particulate matter less than 2.5 µm in diameter for women living near different types of power plants was also determined by using National Environmental Public Health Tracking Network data. Logistic regression models were used to test the hypothesized associations. Women who lived closer to coal and solid waste power plants were exposed to higher levels of particulate matter less than 2.5 µm in diameter compared with other types. We observed a 1.8% (95% confidence interval (CI): 1.3, 2.3) increased odds for PTD, 2.2% (95% CI: 1.0, 3.4) for VPTD, and 1.1% (95% CI: 0.2, 2.0) for term LBW for each 5 km closer to any power plant. When stratifying by different fuel type, we found that only solid waste had an association with term LBW, whereas oil, gas, and solid waste all had an association with PTD and VPTD. Results were consistent when exposure was categorized by number of power plants. Our study found evidence of increasing odds of adverse birth outcomes among infants born to pregnant women living closer to power plants. More research is warranted to better understand the causal relationship.

The effects of air pollution on adverse birth outcomes.

BACKGROUND: Air pollution has been shown to have adverse effects on many health outcomes including cardiorespiratory diseases and cancer. However, evidence on the effects of prenatal exposure is still limited. The purpose of this retrospective cohort study is to evaluate the effects of prenatal exposure to air pollutants including particulate matter with aerodynamic diameter less than 2.5 µm (PM2.5) and ozone (O3) on the risk of adverse birth outcomes (ABOs) including term low birth weight (LBW), preterm delivery (PTD) and very PTD (VPTD). METHODS: singleton births from 2004 to 2005 in Florida were included in the study (N=423,719). Trimester-specific exposures to O3 and PM2.5 at maternal residence at delivery were estimated using the National Environmental Public Health Tracking Network data, which were interpolated using Hierarchical Bayesian models. RESULTS: After adjustment for potential confounders such as demographics, medical and lifestyle factors PM2.5 exposures in all trimesters were found to be significantly and positively associated with the risk of all ABOs. Second-trimester exposure had the strongest effects. For an interquartile range (IQR) increase in PM2.5 during the second trimester, the risk of term LBW, PTD and VPTD increased by 3% [95% confidence interval (CI): 1-6%)], 12% (11-14%) and 22% (18-25%), respectively. O3 was also found to be positively associated with PTD and VPTD with the strongest effects over the whole pregnancy period [3% (1-5%) for PTD and 13% (7-19%) for VPTD for each IQR increase]. However, O3 was observed to have protective effects on term LBW. Results were consistent for multi-pollutant models. CONCLUSION: PM2.5 has consistent adverse effects on ABOs whereas O3 has inconsistent effects. These findings warrant further investigation.

Al-Anon family groups' newcomers and members: Concerns about the drinkers in their lives.

BACKGROUND AND OBJECTIVES: Despite Al-Anon's widespread availability and use, knowledge is lacking about the drinkers in attendees' lives. We filled this gap by describing and comparing Al-Anon newcomers' and members' reports about their "main drinker" (main person prompting initial attendance). METHODS: Al-Anon's World Service Office mailed a random sample of groups, yielding completed surveys from newcomers (N = 362) and stable members (N = 265). RESULTS: Newcomers' and members' drinkers generally were comparable. They had known their drinker for an average of 22 years and been concerned about his or her's drinking for 9 years; about 50% had daily contact with the drinker. Most reported negative relationship aspects (drinker gets on your nerves; you disagree about important things). Newcomers had more concern about the drinker's alcohol use than members did, and were more likely to report their drinkers' driving under the influence. Drinkers' most frequent problem due to drinking was family arguments, and most common source of help was 12-step groups, with lower rates among drinkers of newcomers. Concerns spurring initial Al-Anon attendance were the drinker's poor quality of life, relationships, and psychological status; goals for initial attendance reflected these concerns. DISCUSSION AND CONCLUSIONS: The drinker's alcohol use was of less concern in prompting initial Al-Anon attendance, and, accordingly, the drinker's reduced drinking was a less frequently endorsed goal of attendance. SCIENTIFIC SIGNIFICANCE: Family treatments for substance use problems might expand interventions and outcome domains beyond abstinence and relationship satisfaction to include the drinker's quality of life and psychological symptoms and in turn relieve concerns of family members.

The Effects of Poor Neonatal Health on Children's Cognitive Development.

We make use of a new data resource--merged birth and school records for all children born in Florida from 1992 to 2002--to study the relationship between birth weight and cognitive development. Using singletons as well as twin and sibling fixed effects models, we find that the effects of early health on cognitive development are essentially constant through the school career; that these effects are similar across a wide range of family backgrounds; and that they are invariant to measures of school quality. We conclude that the effects of early health on adult outcomes are therefore set very early.

Ambient Air Pollution and Hypertensive Disorders of Pregnancy: A Systematic Review and Meta-analysis.

Hypertensive disorders of pregnancy (HDP, including gestational hypertension, preeclampsia, and eclampsia) have a substantial public health impact. Maternal exposure to high levels of air pollution may trigger HDP, but this association remains unclear. The objective of our report is to assess and quantify the association between maternal exposures to criteria air pollutants (ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter ≤ 10, 2.5 µm) on HDP risk. PubMed, EMBASE, MEDLINE, Current Contents, Global Health, and Cochrane were searched (last search: September, 2013). After a detailed screening of 270 studies, 10 studies were extracted. We conducted meta-analyses if a pollutant in a specific exposure window was reported by at least four studies. Using fixed- and random-effects models, odds ratios (ORs) and 95% CIs were calculated for each pollutant with specific increment of concentration. Increases in risks of HDP (OR per 10 ppb = 1.16; 95% CI, 1.03-1.30) and preeclampsia (OR per 10 ppb = 1.10; 95% CI, 1.03-1.17) were observed to be associated with exposure to NO2 during the entire pregnancy, and significant associations between HDP and exposure to CO (OR per 1 ppm = 1.79; 95% CI, 1.31-2.45) and O3 (OR per 10 ppb = 1.09; 95% CI, 1.05-1.13) during the first trimester were also observed. Our review suggests an association between ambient air pollution and HDP risk. Although the ORs were relatively low, the population-attributable fractions were not negligible given the ubiquitous nature of air pollution.

Enhancing multi-site autism research through the development of a collaborative data platform.

Data repositories, particularly those storing data on vulnerable populations, increasingly need to carefully consider not only what data is being collected, but how it will be used. As such, the Autism Intervention Research Network on Physical Health (AIR-P) has created the Infrastructure for Collaborative Research (ICR) to establish standards on data collection practices in Autism repositories. The ICR will strive to encourage inter-site collaboration, amplify autistic voices, and widen accessibility to data. The ICR is staged as a three-tiered framework consisting of (1) a request for proposals system, (2) a REDCap-based data repository, and (3) public data dashboards to display aggregate de-identified data. Coupled with a review process including autistic and non-autistic researchers, this framework aims to propel the implementation of equitable autism research, enhance standardization within and between studies, and boost transparency and dissemination of findings. In addition, the inclusion of a contact registry that study participants can opt into creates the base for a robust participant pool. As such, researchers can leverage the platform to identify, reach, and distribute electronic materials to a greater proportion of potential participants who likely fall within their eligibility criteria. By incorporating practices that promote effective communication between researchers and participants, the ICR can facilitate research that is both considerate of and a benefit to autistic people.

The association of maternal pre-pregnancy body mass index with breastfeeding initiation.

Recent evidence extends the health benefits of breastfeeding to include reduction of maternal body mass index (BMI) and childhood obesity. Since most women decide if they will breastfeed prior to pregnancy, it is important to understand, given the high population prevalence of obesity, if maternal underweight, overweight or obese status is associated with breastfeeding initiation. Population-based study. Florida resident birth certificate records. All live singleton births (2004-2009), excluding observations that lacked the primary outcomes of maternal pre-pregnancy BMI and breastfeeding initiation (final sample of 1,161,949 unique observations). Odds of initiating breastfeeding, adjusted by maternal and infant factors, stratified by pre-pregnancy BMI, categorized as underweight, normal, overweight and obese. Adjusting for the known maternal factors associated with breastfeeding initiation, underweight and obese women were significantly less likely to initiate breastfeeding than women with normal BMI, (adjusted odds ratio 0.87, 95 % confidence interval 0.85-0.89 for underweight women; 0.84, 95 % CI 0.83-0.85 for obese women). The magnitude of these findings did not significantly vary by race or ethnicity. Medicaid status and adherence to the Institute of Medicine's 2009 pregnancy weight gain recommendations had only minor influences on breastfeeding initiation. Among adolescents, only underweight status predicted breastfeeding initiation; obesity did not. Underweight and obese women have significantly lower rates of breastfeeding initiation compared to women with normal pre-pregnancy BMI. Future studies need to address the health care, social, and physical barriers that interfere with breastfeeding initiation, especially in underweight and obese women, regardless of race, ethnicity or income.

Identifying indicators during pregnancy for child maltreatment.

To measure the effect of a short interpregnancy interval (IPI), along with other indicators routinely asked during pregnancy on later report of child maltreatment. We hypothesized that an IPI of <18 months was associated with increased risk of child maltreatment. This study was a secondary analysis of a linked population-based dataset from 2005 to 2007 in Florida. Data were derived from three sources: Birth Certificates, Healthy Start Prenatal Risk Screens, and the HomeSafeNet Database. Primary predictor variables were IPI, and mothers' evaluations of the timing of the pregnancy and perceptions of harm. Logistic regression analyses were used to estimate the odds of child maltreatment, adjusting for demographic and other known risk factors for maltreatment. The final study sample consisted of 85,258 multipara women-infant dyads with credible IPIs and with completed Healthy Start Prenatal Risk Screens. Seventeen percent of children had a report of child maltreatment in the first 5 years of life. An IPI of less than 18 months was associated with 18 % higher odds of maltreatment compared to an IPI of greater than 18 months (95 % CI 1.13, 1.23). Mothers' perception of harm and desire to be pregnant at a later time were also significantly associated with higher odds of maltreatment report (AOR = 2.43 95 % CI = 2.17, 2.71 and AOR = 1.18 95 % CI 1.13, 1.24, respectively). Ascertaining short IPI and asking pregnant and peripartum women about their perception of harm and desire for a longer birth spacing can alert obstetricians, family practitioners and pediatricians to potential child maltreatment.

Males at the Tails: How Socioeconomic Status Shapes the Gender Gap.

We document that the female advantage in childhood behavioural and academic outcomes is driven by gender gaps at the extremes of the outcome distribution. Using unconditional quantile regression, we show that family socioeconomic status particularly influences boys' relative to girls' outcomes at the lower tails of the outcome distribution, precisely where gender gaps are most pronounced. These relationships are not explained by school or neighbourhood factors, or parents' differential treatment of boys. The disproportionate effect of socioeconomic status on boys at the tails substantially contributes to the gender gap in high school dropout.

Updates to the Autism Intervention Research Network on Physical Health (AIR-P) Research Agenda.

INTRODUCTION: Autistic individuals, now representing one in 36 individuals in the U.S., experience disproportionate physical health challenges relative to non-autistic individuals. The Health Resources and Services Administration's (HRSA) Autism Intervention Research Network on Physical Health (AIR-P) is an interdisciplinary, multi-center Research Network that aims to increase the health, well-being, and quality of life of autistic individuals. The current paper builds on the initial AIR-P Research Agenda (proposed in Year 1) and provides an updated vision for the Network. METHODS: Updates to the Research Agenda were made via the administration of a Qualtrics survey, and disseminated widely to all AIR-P entities, including the Research Node Leaders, Steering Committee, Autistic Researcher Review Board, and collaborating academic and non-academic entities. Network members were tasked with evaluating the Year 1 Research Agenda and proposing additional priorities. RESULTS: Within each Research Node, all Year 1 priorities were endorsed as continued priorities for research on autism and physical health. Specific topics, including co-occurring conditions and self-determination, advocacy, and decision-making, were particularly endorsed. Opportunities for exploratory studies and intervention research were identified across Research Nodes. Qualitative responses providing feedback on additional research priorities were collected. CONCLUSION: The updated AIR-P Research Agenda represents an important step toward enacting large-scale health promotion efforts for autistic individuals across the lifespan. This updated agenda builds on efforts to catalyze autism research in historically underrepresented topic areas while adopting a neurodiversity-oriented approach to health promotion.

Experimental observations of channel reciprocity in single-mode free-space optical links.

This article describes observations made during a recent series of single-mode lasercom experiments in which high-rate data transmission was demonstrated between a small aircraft and a ground station separated by distances up to 80 km. A significant result of the subsequent data analysis was the discovery of near-unity correlations between the signal fluctuations observed by power monitors at the two ends of the link. This evidence of reciprocity is presented, along with the description of a preliminary concept for utilizing this channel state information to improve link performance.

Towards Replacing Titanium with Copper in the Bipolar Plates for Proton Exchange Membrane Water Electrolysis.

For proton exchange membrane water electrolysis (PEMWE) to become competitive, the cost of stack components, such as bipolar plates (BPP), needs to be reduced. This can be achieved by using coated low-cost materials, such as copper as alternative to titanium. Herein we report on highly corrosion-resistant copper BPP coated with niobium. All investigated samples showed excellent corrosion resistance properties, with corrosion currents lower than 0.1 µA cm-2 in a simulated PEM electrolyzer environment at two different pH values. The physico-chemical properties of the Nb coatings are thoroughly characterized by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). A 30 µm thick Nb coating fully protects the Cu against corrosion due to the formation of a passive oxide layer on its surface, predominantly composed of Nb2O5. The thickness of the passive oxide layer determined by both EIS and XPS is in the range of 10 nm. The results reported here demonstrate the effectiveness of Nb for protecting Cu against corrosion, opening the possibility to use it for the manufacturing of BPP for PEMWE. The latter was confirmed by its successful implementation in a single cell PEMWE based on hydraulic compression technology.

Propagation of data-modulated Gaussian beams through holographic optical elements.

This paper examines dispersion caused by diffraction through uniform volume holographic gratings. Of interest is the impact of this dispersion on the spatial and temporal fidelity of an optical communications signal. To this end, a holographic grating is illuminated by a Gaussian beam with 1/e(2) diameter large compared to the optical wavelength. Coupled-wave analysis is used to calculate the temporal response of the grating to transmitted symbols encoded in time as a train of Gaussian-shaped pulses. It is shown that temporal dispersion due to diffraction impacts bit-error performance, yielding increased power penalty for larger diffraction angles and beam diameters.