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There is limited understanding of the cognitive profiles of Spanish-speaking children with Attention-Deficit/Hyperactivity Disorder (ADHD). The current study investigated the cognitive cluster profiles of Puerto Rican Spanish-speaking children with ADHD using the Wechsler Intelligence Scales for Children-Fourth Edition Spanish (WISC-IV Spanish) Index scores and examined the association between cognitive cluster profiles with other potentially relevant factors.
Hierarchical cluster analysis was used to identify WISC-IV clusters in a sample of 165 Puerto Rican children who had a primary diagnosis of ADHD. To examine the validity of the ADHD clusters, analysis of variances and chi-square analyses were conducted to compare the clusters across sociodemographics (e.g., age and education), type of ADHD diagnosis (ADHD subtype, Learning Disorder comorbidity), and academic achievement.
Clusters were differentiated by level and pattern of performance. A five-cluster solution was identified as optimal that included (C1) multiple cognitive deficits, (C2) processing speed deficits, (C3) generally average performance, (C4) perceptual reasoning strengths, and (C5) working memory deficits. Among the five clusters, the profile with multiple cognitive deficits was characterized by poorer performance on the four WISC-IV Spanish Indexes and was associated with adverse sociodemographic characteristics.
Results illustrate that there is substantial heterogeneity in cognitive abilities of Puerto Rican Spanish-speaking children with ADHD, and this heterogeneity is associated with a number of relevant outcomes.
The mechanism through which developmental programming of offspring overweight/obesity following in utero exposure to maternal overweight/obesity operates is unknown but may operate through biologic pathways involving offspring anthropometry at birth. Thus, we sought to examine to what extent the association between in utero exposure to maternal overweight/obesity and childhood overweight/obesity is mediated by birth anthropometry. Analyses were conducted on a retrospective cohort with data obtained from one hospital system. A natural effects model framework was used to estimate the natural direct effect and natural indirect effect of birth anthropometry (weight, length, head circumference, ponderal index, and small-for-gestational age [SGA] or large-for-gestational age [LGA]) for the association between pre-pregnancy maternal body mass index (BMI) category (overweight/obese vs normal weight) and offspring overweight/obesity in childhood. Models were adjusted for maternal and child socio-demographics. Three thousand nine hundred and fifty mother–child dyads were included in analyses (1467 [57.8%] of mothers and 913 [34.4%] of children were overweight/obese). Results suggest that a small percentage of the effect of maternal pre-pregnancy BMI overweight/obesity on offspring overweight/obesity operated through offspring anthropometry at birth (weight: 15.5%, length: 5.2%, head circumference: 8.5%, ponderal index: 2.2%, SGA: 2.9%, and LGA: 4.2%). There was a small increase in the percentage mediated when gestational diabetes or hypertensive disorders were added to the models. Our study suggests that some measures of birth anthropometry mediate the association between maternal pre-pregnancy overweight/obesity and offspring overweight/obesity in childhood and that the size of this mediated effect is small.
Clostridioides difficile infection (CDI) is the most frequently reported hospital-acquired infection in the United States. Bioaerosols generated during toilet flushing are a possible mechanism for the spread of this pathogen in clinical settings.
To measure the bioaerosol concentration from toilets of patients with CDI before and after flushing.
In this pilot study, bioaerosols were collected 0.15 m, 0.5 m, and 1.0 m from the rims of the toilets in the bathrooms of hospitalized patients with CDI. Inhibitory, selective media were used to detect C. difficile and other facultative anaerobes. Room air was collected continuously for 20 minutes with a bioaerosol sampler before and after toilet flushing. Wilcoxon rank-sum tests were used to assess the difference in bioaerosol production before and after flushing.
Rooms of patients with CDI at University of Iowa Hospitals and Clinics.
Bacteria were positively cultured from 8 of 24 rooms (33%). In total, 72 preflush and 72 postflush samples were collected; 9 of the preflush samples (13%) and 19 of the postflush samples (26%) were culture positive for healthcare-associated bacteria. The predominant species cultured were Enterococcus faecalis, E. faecium, and C. difficile. Compared to the preflush samples, the postflush samples showed significant increases in the concentrations of the 2 large particle-size categories: 5.0 µm (P = .0095) and 10.0 µm (P = .0082).
Bioaerosols produced by toilet flushing potentially contribute to hospital environmental contamination. Prevention measures (eg, toilet lids) should be evaluated as interventions to prevent toilet-associated environmental contamination in clinical settings.
Quality improvement and patient safety (QIPS) competencies are increasingly important in emergency medicine (EM) and are now included in the CanMEDS framework. We conducted a survey aimed at determining the Canadian EM residents’ perspectives on the level of QIPS education and support available to them.
An electronic survey was distributed to all Canadian EM residents from the Royal College and Family Medicine training streams. The survey consisted of multiple-choice, Likert, and free-text entry questions aimed at understanding familiarity with QIPS, local opportunities for QIPS projects and mentorship, and the desire for further QIPS education and involvement.
Of 535 EM residents, 189 (35.3%) completed the survey, representing all 17 medical schools; 77.2% of respondents were from the Royal College stream; 17.5% of respondents reported that QIPS methodologies were formally taught in their residency program; 54.7% of respondents reported being “somewhat” or “very” familiar with QIPS; 47.2% and 51.5% of respondents reported either “not knowing” or “not having readily available” opportunities for QIPS projects and QIPS mentorship, respectively; 66.9% of respondents indicated a desire for increased QIPS teaching; and 70.4% were interested in becoming involved with QIPS training and initiatives.
Many Canadian EM residents perceive a lack of QIPS educational opportunities and support in their local setting. They are interested in receiving more QIPS education, as well as project and mentorship opportunities. Supporting residents with a robust QIPS educational and mentorship framework may build a cohort of providers who can enhance the local delivery of care.
This study examined the long-term effects of a randomized controlled trial of the Family Check-Up (FCU) intervention initiated at age 2 on inhibitory control in middle childhood and adolescent internalizing and externalizing problems. We hypothesized that the FCU would promote higher inhibitory control in middle childhood relative to the control group, which in turn would be associated with lower internalizing and externalizing symptomology at age 14. Participants were 731 families, with half (n = 367) of the families assigned to the FCU intervention. Using an intent-to-treat design, results indicate that the FCU intervention was indirectly associated with both lower internalizing and externalizing symptoms at age 14 via its effect on increased inhibitory control in middle childhood (i.e., ages 8.5–10.5). Findings highlight the potential for interventions initiated in toddlerhood to have long-term impacts on self-regulation processes, which can further reduce the risk for behavioral and emotional difficulties in adolescence.
Early irritability predicts a broad spectrum of psychopathology spanning both internalizing and externalizing disorders, rather than any particular disorder or group of disorders (i.e. multifinality). Very few studies, however, have examined the developmental mechanisms by which it leads to such phenotypically diverse outcomes. We examined whether variation in the diurnal pattern of cortisol moderates developmental pathways between preschool irritability and the subsequent emergence of internalizing and externalizing symptoms 9 years later.
When children were 3 years old, mothers were interviewed about children's irritability and completed questionnaires about their children's psychopathology. Six years later, children collected saliva samples at wake-up and bedtime on three consecutive days. Diurnal cortisol patterns were modeled as latent difference scores between evening and morning samples. When children were approximately 12 years old, mothers again completed questionnaires about their children's psychopathology.
Among children with higher levels of irritability at age 3, a steeper diurnal cortisol slope at age 9 predicted greater internalizing symptoms and irritability at age 12, whereas a blunted slope at age 9 predicted greater externalizing symptoms at age 12, adjusting for baseline and concurrent symptoms.
Our results suggest that variation in stress system functioning can predict and differentiate developmental trajectories of early irritability that are relatively more internalizing v. those in which externalizing symptoms dominate in pre-adolescence.
Modern humans evolved in Africa approximately 200,000 years ago (Campbell and Tishkoff 2010). As groups migrated out of Africa they underwent bottlenecks leading to sharp reductions in population size and genetic diversity (Amos and Hoffman 2010; Harpending and Rogers 2000; Ramachandran et al. 2005). To this day, African populations retain the most genetic diversity globally (Auton et al. 2015). In order to survive both within and out of Africa, early human populations had to adapt to their novel environments, including new food resources, colder climates, higher altitudes, and, especially, infectious diseases (Balaresque et al. 2007; Fumagalli et al. 2011). These adaptive requirements, facilitated by natural selection, led to an increased frequency of alleles that were beneficial in that environment. Due to the fact that these adaptive requirements were driven by local environmental pressures, some of these evolutionarily advantageous alleles display geographic and ancestral specificity, as observed in the genomes of present-day humans (Fumagalli et al. 2011).
The geomagnetic field extending outward beyond Earth’s solid surface encounters a strong, highly variable flow of hot ionized gas from the Sun called the solar wind. This compresses and shapes the dayside of Earth’s magnetic field. On the night (anti-sunward) side of the Earth, the magnetic field gets drawn out into a long, comet-like tail. Present evidence is that this magnetotail region extends to hundreds or thousands of Earth radii. Research over the past six decades has revealed much about the various current systems that shape the Earth’s "magnetosphere". This chapter is devoted to providing a broad overview of the individual current systems that, acting together, generate the complex and fascinating geomagnetic field.
We examined Clostridioides difficile infection (CDI) prevention practices and their relationship with hospital-onset healthcare facility-associated CDI rates (CDI rates) in Veterans Affairs (VA) acute-care facilities.
From January 2017 to February 2017, we conducted an electronic survey of CDI prevention practices and hospital characteristics in the VA. We linked survey data with CDI rate data for the period January 2015 to December 2016. We stratified facilities according to whether their overall CDI rate per 10,000 bed days of care was above or below the national VA mean CDI rate. We examined whether specific CDI prevention practices were associated with an increased risk of a CDI rate above the national VA mean CDI rate.
All 126 facilities responded (100% response rate). Since implementing CDI prevention practices in July 2012, 60 of 123 facilities (49%) reported a decrease in CDI rates; 22 of 123 facilities (18%) reported an increase, and 41 of 123 (33%) reported no change. Facilities reporting an increase in the CDI rate (vs those reporting a decrease) after implementing prevention practices were 2.54 times more likely to have CDI rates that were above the national mean CDI rate. Whether a facility’s CDI rates were above or below the national mean CDI rate was not associated with self-reported cleaning practices, duration of contact precautions, availability of private rooms, or certification of infection preventionists in infection prevention.
We found considerable variation in CDI rates. We were unable to identify which particular CDI prevention practices (i.e., bundle components) were associated with lower CDI rates.
There is an emerging consensus in developmental psychopathology that irritable youth are at risk for developing internalizing problems later in life. The current study explored if irritability in youth is multifactorial and the impact of irritability dimensions on psychopathology outcomes in adulthood.
We conducted exploratory factor analysis on irritability symptom items from a semi-structured diagnostic interview administered to a community sample of adolescents (ages 14–19; 42.7% male; 89.1% white). The analysis identified two factors corresponding to items from the mood disorders v. the oppositional defiant disorder (ODD) (Leibenluft and Stoddard) sections of the interview. These factors were then entered together into regression models predicting psychopathology assessed at age 24 (N = 941) and again at age 30 (N = 816). All models controlled for concurrent psychopathology in youth.
The two irritability dimensions demonstrated different patterns of prospective relationships, with items from the ODD section primarily predicting externalizing psychopathology, items from the mood disorder sections predicting depression at age 24 but not 30, and both dimensions predicting borderline personality disorder symptoms.
These results suggest that the current standard of extracting and compositing irritability symptom items from diagnostic interviews masks distinct dimensions of irritability with different psychopathological outcomes. Additionally, these findings add nuance to the prevailing notion that irritability in youth is specifically linked to later internalizing problems. Further investigation using more sensitive and multifaceted measures of irritability are needed to parse the meaning and clinical implications of these dimensions.
This chapter presents an overview of the motivation for the volume, emphasizing why studying deep carbon is relevant to the goal of understanding carbon quantities, movements, forms, and origins. It contains brief highlights of the new instruments, cross-cutting research initiatives, and deep carbon science over the past decade (spurred in large part by the international Deep Carbon Observatory) that have expanded our understanding of carbon on Earth.
Classic conceptual frameworks explaining the relationship of personality traits to depression include the precursor and predisposition models. The former hypothesizes that depression is predicted by traits alone whereas the latter hypothesizes that stress, together with personality, predicts depression. Dynamic vulnerability models (DVM) expand on these perspectives by incorporating fluctuations in personality over time. The stress generation model provides an alternative view, positing that depression generates stress, creating a self-perpetuating cycle. However, these conceptual models are rarely directly compared.
We tested these models, focusing on neuroticism and stressful life events that the participant may have contributed to, using path analysis in a sample of 550 never-depressed, adolescent females assessed five times over 3 years.
A dynamic precursor model with stress generation was best supported. For the precursor component, neuroticism predicted subsequent depression across four assessment intervals. For the dynamic trait component, stressful life events predicted subsequent neuroticism at three of four intervals. Finally, in line with stress generation, depression consistently predicted subsequent stressful life events, and life events then predicted depression.
Finding support for the DVM is noteworthy, as this is the first comprehensive test of this model. Moreover, results supported integrating stress generation with trait vulnerability. Continued use of integrated approaches and refining the statistical implementation of these theories is necessary to advance understanding of the development of depression.
Patients with major depressive disorder (MDD) display cognitive deficits in acutely depressed and remitted states. Childhood maltreatment is associated with cognitive dysfunction in adults, but its impact on cognition and treatment related cognitive outcomes in adult MDD has received little consideration. We investigate whether, compared to patients without maltreatment and healthy participants, adult MDD patients with childhood maltreatment display greater cognitive deficits in acute depression, lower treatment-associated cognitive improvements, and lower cognitive performance in remission.
Healthy and acutely depressed MDD participants were enrolled in a multi-center MDD predictive marker discovery trial. MDD participants received 16 weeks of standardized antidepressant treatment. Maltreatment and cognition were assessed with the Childhood Experience of Care and Abuse interview and the CNS Vital Signs battery, respectively. Cognitive scores and change from baseline to week 16 were compared amongst MDD participants with (DM+, n = 93) and without maltreatment (DM−, n = 90), and healthy participants with (HM+, n = 22) and without maltreatment (HM−, n = 80). Separate analyses in MDD participants who remitted were conducted.
DM+ had lower baseline global cognition, processing speed, and memory v. HM−, with no significant baseline differences amongst DM−, HM+, and HM− groups. There were no significant between-group differences in cognitive change over 16 weeks. Post-treatment remitted DM+, but not remitted DM−, scored significantly lower than HM− in working memory and processing speed.
Childhood maltreatment was associated with cognitive deficits in depressed and remitted adults with MDD. Maltreatment may be a risk factor for more severe and persistent cognitive deficits in adult MDD.
Carbon is one of the most important elements of our planet, and ninety percent of it resides inside Earth's interior. This book summarizes ten years of research by scientists involved in the Deep Carbon Observatory, a global community of 1200 scientists. It is a comprehensive guide to carbon inside Earth, including its quantities, movements, forms, origins, changes over time, and impact on planetary processes. Leading experts from a variety of fields, including geoscience, biology, chemistry, and physics, provide exciting new insights into the interconnected nature of the global carbon cycle, and explain why it matters to the past, present, and future of our planet. With end-of-chapter problems, illustrative infographics, full-color images, and access to online models and datasets, it is a valuable reference for graduate students, researchers, and professional scientists interested in carbon cycling and Earth system science. This title is also available as Open Access on Cambridge Core.
Exposure to high levels of postdivorce interparental conflict is a well-documented risk factor for the development of psychopathology, and there is strong evidence of a subpopulation of families for which conflict persists for many years after divorce. However, existing studies have not elucidated differential trajectories of conflict within families over time, nor have they assessed the risk posed by conflict trajectories for development of psychopathology or evaluated potential protective effects of children's coping to mitigate such risk. We used growth mixture modeling to identify longitudinal trajectories of child-reported conflict over a period of six to eight years following divorce in a sample of 240 children. We related the trajectories to children's mental health problems, substance use, and risky sexual behaviors and assessed how children's coping prospectively predicted psychopathology in the different conflict trajectories. We identified three distinct trajectories of conflict; youth in two high-conflict trajectories showed deleterious effects on measures of psychopathology at baseline and the six-year follow-up. We found both main effects of coping and coping by conflict trajectory interaction effects in predicting problem outcomes at the six-year follow-up. The study supports the notion that improving youth's general capacity to cope adaptively is a potentially modifiable protective factor for all children facing parental divorce and that children in families with high levels of postdivorce conflict are a particularly appropriate group to target for coping-focused preventive interventions.
The Early Growth and Development Study (EGDS) is a prospective adoption study of birth parents, adoptive parents and adopted children (n = 561 adoptees). The original sample has been expanded to include siblings of the EGDS adoptees who were reared by the birth mother and assessed beginning at age 7 years (n = 217 biological children), and additional siblings in both the birth and adoptive family homes, recruited when the adoptees were 8–15 years old (n = 823). The overall study aims are to examine how family, peer and contextual processes affect child and adolescent adjustment, and to examine their interplay (mediation, moderation) with genetic influences. Adoptive and birth parents were originally recruited through adoption agencies located throughout the USA following the birth of a child. Assessments are ongoing and occurred in 9 month’s intervals until the adoptees turned 3 years of age, and in 1 to 2 year intervals thereafter through age 15. Data collection includes the following primary constructs: child temperament, behavior problems, mental health, peer relations, executive functioning, school performance and health; birth and adoptive parent personality characteristics, mental health, health, context, substance use, parenting and marital relations; and the prenatal environment. Findings highlight the power of the adoption design to detect environmental influences on child development and provide evidence of complex interactions and correlations between genetic, prenatal environmental and postnatal environmental influences on a range of child outcomes. The study sample, procedures and an overview of findings are summarized and ongoing assessment activities are described.
Disturbances in trait emotions are a predominant feature in schizophrenia. However, less is known about (a) differences in trait emotion across phases of the illness such as the clinical high-risk (CHR) phase and (b) whether abnormalities in trait emotion that are associated with negative symptoms are driven by primary (i.e. idiopathic) or secondary (e.g. depression, anxiety) factors.
To examine profiles of trait affective disturbance and their clinical correlates in individuals with schizophrenia and individuals at CHR for psychosis.
In two studies (sample 1: 56 out-patients diagnosed with schizophrenia and 34 demographically matched individuals without schizophrenia (controls); sample 2: 50 individuals at CHR and 56 individuals not at CHR (controls)), participants completed self-report trait positive affect and negative affect questionnaires, clinical symptom interviews (positive, negative, disorganised, depression, anxiety) and community-based functional outcome measures.
Both clinical groups reported lower levels of positive affect (specific to joy among individuals with schizophrenia) and higher levels of negative affect compared with controls. For individuals with schizophrenia, links were found between positive affect and negative symptoms (which remained after controlling for secondary factors) and between negative affect and positive symptoms. For individuals at CHR, links were found between both affect dimensions and both types of symptom (which were largely accounted for by secondary factors).
Both clinical groups showed some evidence of reduced trait positive affect and elevated trait negative affect, suggesting that increasing trait positive affect and reducing trait negative affect is an important treatment goal across both populations. Clinical correlates of these emotional abnormalities were more integrally linked to clinical symptoms in individuals with schizophrenia and more closely linked to secondary influences such as depression and anxiety in individuals at CHR.