Health and development of children born after assisted reproductive technology and sub-fertility compared to naturally conceived children: data from a national study

In a non-matched case-control study using data from two large national cohort studies, we investigated whether indicators of child health and development up to 7 years of age differ between children conceived using assisted reproductive technology (ART), children born after sub-fertility (more than 24 months of trying for conception) and other children. Information on ART use/sub-fertility was available for 23,649 children. There were 227 cases (children conceived through ART) and two control groups: 783 children born to sub-fertile couples, and 22,639 children born to couples with no fertility issues. In models adjusted for social and demographic factors there were significant differences between groups in rate of hospital admissions before the children were 9 months old (P=0.029), with the ART group showing higher rates of hospital admission than the no fertility issues control group, the sub-fertile control group being intermediate between the two. Children born after ART had comparable health and development beyond 9 months of age to their naturally conceived peers. This applied to the whole sample and to a sub-sample of children from deprived neighborhoods

The health and development of children born to older mothers in the United Kingdom: observational study using longitudinal cohort data

Objective: To assess relations between children’s health and development and maternal age. Design: Observational study of longitudinal cohorts. Setting: Millennium Cohort Study (a random sample of UK children) and the National Evaluation of Sure Start study (a random sample of children in deprived areas in England), 2001 to 2007. Participants: 31 257 children at age 9 months, 24 781 children at age 3 years, and 22 504 at age 5 years. Main outcome measures: Childhood unintentional injuries and hospital admissions (aged 9 months, 3 years, and 5 years), immunisations (aged 9 months and 3 years), body mass index, language development, and difficulties with social development (aged 3 and 5 years). Results: Associations were independent of personal and family characteristics and parity. The risk of children having unintentional injuries requiring medical attention or being admitted to hospital both declined with increasing maternal age. For example, at three years the risk of unintentional injuries declined from 36.6% for mothers aged 20 to 28.6% for mothers aged 40 and hospital admissions declined, respectively, from 27.1% to 21.6%. Immunisation rates at nine months increased with maternal age from 94.6% for mothers aged 20 to 98.1% for mothers aged 40. At three years, immunisation rates reached a maximum, at 81.3% for mothers aged 27, being lower for younger and older mothers. This was linked to rates for the combined measles, mumps, and rubella immunisation because excluding these resulted in no significant relation with maternal age. An increase in overweight children at ages 3 and 5 years associated with increasing maternal age was eliminated once maternal body mass index was included as a covariate. Language development was associated with improvements with increasing maternal age, with scores for children of mothers aged 20 being lower than those of children of mothers aged 40 by 0.21 to 0.22 standard deviations at ages 3 and 4 years. There were fewer social and emotional difficulties associated with increasing maternal age. Children of teenage mothers had more difficulties than children of mothers aged 40 (difference 0.28 SD at age 3 and 0.16 SD at age 5). Conclusion: Increasing maternal age was associated with improved health and development for children up to 5 years of age

Decision trees in epidemiological research

Background: In many studies, it is of interest to identify population subgroups that are relatively homogeneous with respect to an outcome. The nature of these subgroups can provide insight into effect mechanisms and suggest targets for tailored interventions. However, identifying relevant subgroups can be challenging with standard statistical methods. Main text: We review the literature on decision trees, a family of techniques for partitioning the population, on the basis of covariates, into distinct subgroups who share similar values of an outcome variable. We compare two decision tree methods, the popular Classification and Regression tree (CART) technique and the newer Conditional Inference tree (CTree) technique, assessing their performance in a simulation study and using data from the Box Lunch Study, a randomized controlled trial of a portion size intervention. Both CART and CTree identify homogeneous population subgroups and offer improved prediction accuracy relative to regression-based approaches when subgroups are truly present in the data. An important distinction between CART and CTree is that the latter uses a formal statistical hypothesis testing framework in building decision trees, which simplifies the process of identifying and interpreting the final tree model. We also introduce a novel way to visualize the subgroups defined by decision trees. Our novel graphical visualization provides a more scientifically meaningful characterization of the subgroups identified by decision trees. Conclusions: Decision trees are a useful tool for identifying homogeneous subgroups defined by combinations of individual characteristics. While all decision tree techniques generate subgroups, we advocate the use of the newer CTree technique due to its simplicity and ease of interpretation

From wallet to mobile: exploring how mobile payments create customer value in the service experience

This study explores how mobile proximity payments (MPP) (e.g., Apple Pay) create customer value in the service experience compared to traditional payment methods (e.g. cash and card). The main objectives were firstly to understand how customer value manifests as an outcome in the MPP service experience, and secondly to understand how the customer activities in the process of using MPP create customer value. To achieve these objectives a conceptual framework is built upon the Grönroos-Voima Value Model (Grönroos and Voima, 2013), and uses the Theory of Consumption Value (Sheth et al., 1991) to determine the customer value constructs for MPP, which is complimented with Script theory (Abelson, 1981) to determine the value creating activities the consumer does in the process of paying with MPP. The study uses a sequential exploratory mixed methods design, wherein the first qualitative stage uses two methods, self-observations (n=200) and semi-structured interviews (n=18). The subsequent second quantitative stage uses an online survey (n=441) and Structural Equation Modelling analysis to further examine the relationships and effect between the value creating activities and customer value constructs identified in stage one. The academic contributions include the development of a model of mobile payment services value creation in the service experience, introducing the concept of in-use barriers which occur after adoption and constrains the consumers existing use of MPP, and revealing the importance of the mobile in-hand momentary condition as an antecedent state. Additionally, the customer value perspective of this thesis demonstrates an alternative to the dominant Information Technology approaches to researching mobile payments and broadens the view of technology from purely an object a user interacts with to an object that is immersed in consumers’ daily life

Paternal age, paternal presence and children’s health: an observational study

In an observational study of 31,257 children we investigated the effects of paternal age at the time of the child’s birth, paternal absence and non-biological fathers on children’s health. Results are per 5 year change in paternal age. Older fathers were associated with lower rates of unintentional injuries, odds ratio (OR)=0.966, P=0.0027. There was a quadratic association between paternal age and risk of hospital admission, β=0.0121, P=0.0109, with minimum risk at paternal age37.7. Absent fathers were associated with increased risk of hospital admission, OR=1.19,P<10-3, lower rates of complete immunizations to 9 months, OR=0.562, P<10-3, higher Strength and Difficulties Questionnaire (SDQ) difficulties scores: β=0.304, P=0.0024 (3 year olds), β=0.697, P<10-3 (5 year olds). Non-biological fathers were associated with increased risk of unintentional injury, OR=1.16, P=0.0319 and hospital admission,OR=1.26, P=0.0166; lower rates of complete immunizations to 9 months, OR=0.343, P=0.0309 and higher SDQ difficulties scores:β=0.908, P<10-3

Individual, family and neighbourhood factors related to life satisfaction and perceived discrimination among low-income, non-immigrant mothers in seven European countries

We examined associations between dimensions of social exclusion and maternal life satisfaction and maternal perceived discrimination for low-income, non-immigrant mothers of children at preschool and primary school age in seven European countries (Czech Republic, England, Germany, Greece, Italy, Poland, Portugal – N = 1227), using standardized survey data from a large-scale interview study. Life satisfaction and perceived discrimination were found to be associated, indicating that both dimensions are important to consider in relation to subjective well-being. The results of linear mixed effect regression models demonstrated that lack of resources in multiple dimensions of social exclusion were linked to our well-being measures, including objective life condition variables (material deprivation, poor neighbourhood quality; both outcomes) as well as more relational aspects (unemployment, less social support; life satisfaction) and adult literacy related difficulties (perceived discrimination). These findings reaffirm the importance of combatting social exclusion. There are implications for public policy, emphasizing the importance of joined-up policies that tackle different forms of exclusion

Differential trial-type effects in an Implicit Relational Assessment Procedure: Extending the DAARRE model

The differential arbitrarily applicable relational responding effects (DAARRE) model predicts two effects on the Implicit Relational Assessment Procedure (IRAP): the single trial-type dominance effect (STTDE) and the dissonant-target trial-type effect (DTTTE). We sought to explore variables that modulate these effects. Forty-two participants completed an IRAP, meeting the practice criteria (median latency ≤ 2000ms and accuracy ≥ 80% correct) and thus proceeding to six test blocks. The IRAP had four trial-types: trial-type 1: happy-face—happy-word; trial-type 2: happy-face—fear-word; trial-type 3: fear-face—happy-word; trial-type 4: fear-face—fear-word. Participants were randomly assigned to start with a consistent (respond True, False, False, True, respectively, to the four trial-types) or inconsistent (opposite responding) block. Difference (DIRAP) scores were calculated (inconsistent minus consistent latencies). A significantly larger DIRAP score was observed in trial-type 2 relative to trial-type 3 (a DTTTE), but only for participants who started with the inconsistent block. A “happiness superiority” STTDE (i.e., larger DIRAP score on trial-type 1 relative to trial-type 4) was observed, but only for participants who failed to maintain the criteria at the trial-type level (in any of the trial-types). Overall, the findings highlight the importance of distinguishing between the functional versus relational properties of the stimuli presented within an IRAP. The modulation of the DTTTE is interpreted in terms of functional coherence between the target and response option in inconsistent blocks. A novel data-analytic algorithm is presented to identify performance criteria violations at the trial-type level. The findings suggest that a greater focus is required in Relational Frame Theory on the impact of the functional properties of stimuli on relational framing

Antarctic macrobenthic communities: a compilation of circumpolar information

Comprehensive information on Antarctic macrobenthic community structure has been publicly available since the 1960s. It stems from trawl, dredge, grab, and corer samples as well as from direct and camera observations (Table 1–2). The quality of this information varies considerably; it consists of pure descriptions, figures for presence (absence) and abundance of some key taxa or proxies for such parameters, e.g. sea-floor cover. Some data sets even cover a defined and complete proportion of the macrobenthos with further analyses on diversity and zoogeography. As a consequence the acquisition of data from approximately 90 different campaigns assembled here was not standardised. Nevertheless, it was possible to classify this broad variety of known macrobenthic assemblages to the best of expert knowledge (Gutt 2007; Fig. 1). This overview does not replace statistically sound community and diversity analyses. However, it shows from where which kind of information is available and it acts as an example of the feasibility and power of such data collections. The data set provides unique georeferenced biological basic information for the planning of future coordinated research activities, e.g. under the umbrella of the biology program “Antarctic Thresholds - Ecosystem Resilience and Adaptation” (AnT-ERA) of the Scientific Committee on Antarctic Research (SCAR) and especially for actual conservation issues, e.g. the planning of Marine Protected Areas (MPAs) by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR)

Measurement of Spin-orbit Misalignment and Nodal Precession for the Planet around Pre-main-sequence Star PTFO 8-8695 from Gravity Darkening

PTFO 8-8695b represents the first transiting exoplanet candidate orbiting a pre-main-sequence star (van Eyken et al. 2012, ApJ, 755, 42). We find that the unusual lightcurve shapes of PTFO 8-8695 can be explained by transits of a planet across an oblate, gravity-darkened stellar disk. We develop a theoretical framework for understanding precession of a planetary orbit's ascending node for the case when the stellar rotational angular momentum and the planetary orbital angular momentum are comparable in magnitude. We then implement those ideas to simultaneously and self-consistently fit two separate lightcurves observed in 2009 December and 2010 December. Our two self-consistent fits yield Mp = 3.0 M_Jup and Mp = 3.6 M_Jup for assumed stellar masses of M* = 0.34 M_☉ and M* = 0.44 M_☉ respectively. The two fits have precession periods of 293 days and 581 days. These mass determinations (consistent with previous upper limits) along with the strength of the gravity-darkened precessing model together validate PTFO 8-8695b as just the second hot Jupiter known to orbit an M-dwarf. Our fits show a high degree of spin-orbit misalignment in the PTFO 8-8695 system: 69° ± 2° or 73°.1 ± 0°.5, in the two cases. The large misalignment is consistent with the hypothesis that planets become hot Jupiters with random orbital plane alignments early in a system's lifetime. We predict that as a result of the highly misaligned, precessing system, the transits should disappear for months at a time over the course of the system's precession period. The precessing, gravity-darkened model also predicts other observable effects: changing orbit inclination that could be detected by radial velocity observations, changing stellar inclination that would manifest as varying vsin i, changing projected spin-orbit alignment that could be seen by the Rossiter–McLaughlin effect, changing transit shapes over the course of the precession, and differing lightcurves as a function of wavelength. Our measured planet radii of 1.64 R_Jup and 1.68 R_Jup in each case are consistent with a young, hydrogen-dominated planet that results from a "hot-start" formation mechanism

Rapid Detection and Quantification of Triacylglycerol by HPLC–ELSD in \u3ci\u3eChlamydomonas reinhardtii\u3c/i\u3e and \u3ci\u3eChlorella\u3c/i\u3e Strains

Triacylglycerol (TAG) analysis and quantification are commonly performed by first obtaining a purified TAG fraction from a total neutral lipid extract using thinlayer chromatography (TLC), and then analyzing the fatty acid composition of the purified TAG fraction by gas chromatography (GC). This process is time-consuming, labor intensive and is not suitable for analysis of small sample sizes or large numbers. A rapid and efficient method for monitoring oil accumulation in algae using high performance liquid chromatography for separation of all lipid classes combined with detection by evaporative light scattering (HPLC–ELSD) was developed and compared to the conventional TLC/GC method. TAG accumulation in two Chlamydomonas reinhardtii (21 gr and CC503) and three Chlorella strains (UTEX 1230, CS01 and UTEX 2229) grown under conditions of nitrogen depletion was measured. The TAG levels were found to be 3–6 % DW (Chlamydomonas strains) and 7–12 % DW (Chlorella strains) respectively by both HPLC–ELSD and TLC/GC methods. HPLC–ELSD resolved the major lipid classes such as carotenoids, TAG, diacylglycerol (DAG), free fatty acids, phospholipids, and galactolipids in a 15-min run. Quantitation of TAG content was based on comparison to calibration curves of trihexadecanoin (16:0 TAG) and trioctadecadienoin (18:2 TAG) and showed linearity from 0.2 to 10 lg. Algal TAG levels \u3e0.5 lg/g DW were detectable by this method. Furthermore TAG content in Chlorella kessleri UTEX 2229 could be detected. TAG as well as DAG and TAG content were estimated at 1.6 % DWby HPLC–ELSD, while it was undetectable by TLC/GC method