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This chapter addresses multicultural perspectives of intelligence in the United States. Topics include fairness in testing; environment, social location, and cultural context; measures of intelligence; and outcome implications in testing ethnocultural populations. Definitions of intelligence from a cultural perspective are highlighted. Contextual factors include: poverty, home environment, education, fluency in English, and acculturation. Testing constructs such as fairness in testing, test bias, cultural loading, and various forms of testing equivalence are discussed. Alternative assessment practices focus on nonverbal intelligence tests; dynamic assessment procedures; performance-based, authentic, and curriculum-based assessment; response to intervention, think aloud protocols, cross-battery assessment; and a multidimensional bilingual assessment model. Usage of mainstream intelligence tests is discussed in relation to Black, Asian, American Indian/Native American, and Hispanic and Latino/a communities. The numerous challenges, controversies, and complexities of interpreting test scores in cultural contexts are discussed as intelligence tests are transported, renormed, and restandardized globally.
Parrondo’s coin-tossing games were introduced as a toy model of the flashing Brownian ratchet in statistical physics but have emerged as a paradigm for a much broader phenomenon that occurs if there is a reversal in direction in some system parameter when two similar dynamics are combined. Our focus here, however, is on the original Parrondo games, usually labeled A and B. We show that if the parameters of the games are allowed to be arbitrary, subject to a fairness constraint, and if the two (fair) games A and B are played in an arbitrary periodic sequence, then the rate of profit can not only be positive (the so-called Parrondo effect), but can also be arbitrarily close to 1 (i.e. 100%).
There is strong public belief that polyunsaturated fats protect against and ameliorate depression and anxiety.
To assess effects of increasing omega-3, omega-6 or total polyunsaturated fat on prevention and treatment of depression and anxiety symptoms.
We searched widely (Central, Medline and EMBASE to April 2017, trial registers to September 2016, ongoing trials updated to August 2019), including trials of adults with or without depression or anxiety, randomised to increased omega-3, omega-6 or total polyunsaturated fat for ≥24 weeks, excluding multifactorial interventions. Inclusion, data extraction and risk of bias were assessed independently in duplicate, and authors contacted for further data. We used random-effects meta-analysis, sensitivity analyses, subgrouping and Grading of Recommendations, Assessment, Development and Evaluations (GRADE) assessment.
We included 31 trials assessing effects of long-chain omega-3 (n = 41 470), one of alpha-linolenic acid (n = 4837), one of total polyunsaturated fat (n = 4997) and none of omega-6. Meta-analysis suggested that increasing long-chain omega-3 probably has little or no effect on risk of depression symptoms (risk ratio 1.01, 95% CI 0.92–1.10, I2 = 0%, median dose 0.95 g/d, duration 12 months) or anxiety symptoms (standardised mean difference 0.15, 95% CI 0.05–0.26, I2 = 0%, median dose 1.1 g/d, duration 6 months; both moderate-quality evidence). Evidence of effects on depression severity and remission in existing depression were unclear (very-low-quality evidence). Results did not differ by risk of bias, omega-3 dose, duration or nutrients replaced. Increasing alpha-linolenic acid by 2 g/d may increase risk of depression symptoms very slightly over 40 months (number needed to harm, 1000).
Long-chain omega-3 supplementation probably has little or no effect in preventing depression or anxiety symptoms.
Declaration of interest
L.H. and A.A. were funded to attend the World Health Organization Nutrition Guidance Expert Advisory Group (NUGAG) Subgroup on Diet and Health meetings and present review results. The authors report no other conflicts of interest.
The present study focused on parents’ social cue use in relation to young children's attention. Participants were ten parent–child dyads; all children were 36 to 60 months old and were either typically developing (TD) or were diagnosed with autism spectrum disorder (ASD). Children wore a head-mounted camera that recorded the proximate child view while their parent played with them. The study compared the following between the TD and ASD groups: (a) frequency of parent's gesture use; (b) parents’ monitoring of their child's face; and (c) how children looked at parents’ gestures. Results from Bayesian estimation indicated that, compared to the TD group, parents of children with ASD produced more gestures, more closely monitored their children's faces, and provided more scaffolding for their children's visual experiences. Our findings suggest the importance of further investigating parents’ visual and gestural scaffolding as a potential developmental mechanism for children's early learning, including for children with ASD.
Abnormal effort-based decision-making represents a potential mechanism underlying motivational deficits (amotivation) in psychotic disorders. Previous research identified effort allocation impairment in chronic schizophrenia and focused mostly on physical effort modality. No study has investigated cognitive effort allocation in first-episode psychosis (FEP).
Cognitive effort allocation was examined in 40 FEP patients and 44 demographically-matched healthy controls, using Cognitive Effort-Discounting (COGED) paradigm which quantified participants’ willingness to expend cognitive effort in terms of explicit, continuous discounting of monetary rewards based on parametrically-varied cognitive demands (levels N of N-back task). Relationship between reward-discounting and amotivation was investigated. Group differences in reward-magnitude and effort-cost sensitivity, and differential associations of these sensitivity indices with amotivation were explored.
Patients displayed significantly greater reward-discounting than controls. In particular, such discounting was most pronounced in patients with high levels of amotivation even when N-back performance and reward base amount were taken into consideration. Moreover, patients exhibited reduced reward-benefit sensitivity and effort-cost sensitivity relative to controls, and that decreased sensitivity to reward-benefit but not effort-cost was correlated with diminished motivation. Reward-discounting and sensitivity indices were generally unrelated to other symptom dimensions, antipsychotic dose and cognitive deficits.
This study provides the first evidence of cognitive effort-based decision-making impairment in FEP, and indicates that decreased effort expenditure is associated with amotivation. Our findings further suggest that abnormal effort allocation and amotivation might primarily be related to blunted reward valuation. Prospective research is required to clarify the utility of effort-based measures in predicting amotivation and functional outcome in FEP.
Anxiety, depression and somatization (the internalizing cluster) are highly comorbid, prevalent and associated with significant individual and societal costs. Although prior studies have examined their natural course, there has been a little investigation into how symptoms unfold at the individual level. We examined the intraindividual (within-person) temporal patterning of symptom development and the impact of risk factors (sex, ethnicity, socioeconomic indicators, bullying victimization, child maltreatment) on symptom means and trajectories (between-person), comparing youth and parent reports.
Over a 7-year interval from age 11 to 17, children (n = 669; 54% girls; 79% White) and parents (89% mothers) reported on symptoms of anxiety and depression from age 11 and somatization from age 13. Autoregressive latent trajectory models with structured residuals were used to uncouple within- and between-person sources of variance.
According to self-reports, generalized anxiety consistently predicted depression, while anxiety and depression consistently predicted somatization. Anxiety also had an indirect effect on somatization via depression. According to parent reports, there were several bidirectional effects between anxiety and depression and between depression and somatization. Experiences of abuse were consistent risk factors for self-reported internalizing symptoms, and across informants, girls had higher symptom means and rising trajectories compared to boys.
Generalized anxiety plays an important role in adolescent depressive and somatic symptoms. Primary prevention of anxiety may be warranted to curb symptom continuity and the development of comorbidity. Research is needed to determine whether self-reports of anxiety should be prioritized over parent reports and continued efforts are needed to reduce bullying and child maltreatment.
Catheter-associated urinary tract infections in 592 hospitals immediately declined after federal value-based incentive program implementation, but this was fully attributable to a concurrent surveillance case definition revision. Post revision, more hospitals had favorable standardized infection ratios, likely leading to artificial inflation of their performance scores unrelated to changes in patient safety.
There have been significant changes in the diagnostic criteria for diffuse gliomas in the 2016 WHO CNS tumor classification, with the incorporation of molecular criteria into a number of definitions. This has placed a greater emphasis on the availability of key immunohistochemical and molecular tests. In order to determine the effect that these changes have had on neuropathology practice and the access of different centres to these tests, we designed a survey that was sent to all members of the Canadian Association of Neuropathology member list in the fall of 2017. This survey asked a number of questions relating to the approach to glioma diagnosis, immunohistochemical/molecular test ordering patterns, in-house test availability, and need to send out for testing. In this presentation we will present preliminary results from this survey, with a focus on institutional testing capabilities. This provides a valuable resource that could ultimately need to a national database of immunohistochemical and molecular test availability for each neuropathology centre.
This presentation will enable the learner to:
1.Review the key molecular markers in the diagnosis of adult gliomas and methods of testing for them
2.Discuss the effect that the 2016 WHO CNS tumor update has had on clinical practice in Canada
Maternal systemic inflammation during pregnancy may restrict embryo−fetal growth, but the extent of this effect remains poorly established in undernourished populations. In a cohort of 653 maternal−newborn dyads participating in a multi-armed, micronutrient supplementation trial in southern Nepal, we investigated associations between maternal inflammation, assessed by serum α1-acid glycoprotein and C-reactive protein, in the first and third trimesters of pregnancy, and newborn weight, length and head and chest circumferences. Median (IQR) maternal concentrations in α1-acid glycoprotein and C-reactive protein in the first and third trimesters were 0.65 (0.53–0.76) and 0.40 (0.33–0.50) g/l, and 0.56 (0.25–1.54) and 1.07 (0.43–2.32) mg/l, respectively. α1-acid glycoprotein was inversely associated with birth size: weight, length, head circumference and chest circumference were lower by 116 g (P = 2.3 × 10−6), and 0.45 (P = 3.1 × 10−5), 0.18 (P = 0.0191) and 0.48 (P = 1.7 × 10−7) cm, respectively, per 50% increase in α1-acid glycoprotein averaged across both trimesters. Adjustment for maternal age, parity, gestational age, nutritional and socio-economic status and daily micronutrient supplementation failed to alter any association. Serum C-reactive protein concentration was largely unassociated with newborn size. In rural Nepal, birth size was inversely associated with low-grade, chronic inflammation during pregnancy as indicated by serum α1-acid glycoprotein.
Better understanding of interplay among symptoms, cognition and functioning in first-episode psychosis (FEP) is crucial to promoting functional recovery. Network analysis is a promising data-driven approach to elucidating complex interactions among psychopathological variables in psychosis, but has not been applied in FEP.
This study employed network analysis to examine inter-relationships among a wide array of variables encompassing psychopathology, premorbid and onset characteristics, cognition, subjective quality-of-life and psychosocial functioning in 323 adult FEP patients in Hong Kong. Graphical Least Absolute Shrinkage and Selection Operator (LASSO) combined with extended Bayesian information criterion (BIC) model selection was used for network construction. Importance of individual nodes in a generated network was quantified by centrality analyses.
Our results showed that amotivation played the most central role and had the strongest associations with other variables in the network, as indexed by node strength. Amotivation and diminished expression displayed differential relationships with other nodes, supporting the validity of two-factor negative symptom structure. Psychosocial functioning was most strongly connected with amotivation and was weakly linked to several other variables. Within cognitive domain, digit span demonstrated the highest centrality and was connected with most of the other cognitive variables. Exploratory analysis revealed no significant gender differences in network structure and global strength.
Our results suggest the pivotal role of amotivation in psychopathology network of FEP and indicate its critical association with psychosocial functioning. Further research is required to verify the clinical significance of diminished motivation on functional outcome in the early course of psychotic illness.
Oxidative stress is implicated in the aetiology of schizophrenia, and the antioxidant defence system (AODS) may be protective in this illness. We examined the major antioxidant glutathione (GSH) in prefrontal brain and its correlates with clinical and demographic variables in schizophrenia.
GSH levels were measured in the dorsolateral prefrontal region of 28 patients with chronic schizophrenia using a magnetic resonance spectroscopy sequence specifically adapted for GSH. We examined correlations of GSH levels with age, age at onset of illness, duration of illness, and clinical symptoms.
We found a negative correlation between GSH levels and age at onset (r = −0.46, p = 0.015), and a trend-level positive relationship between GSH and duration of illness (r = 0.34, p = 0.076).
Our findings are consistent with a possible compensatory upregulation of the AODS with longer duration of illness and suggest that the AODS may play a role in schizophrenia.
Several life-threatening diseases of the kidney have their origins in mutational events that occur during embryonic development. In this study, we investigate the role of the Wolffian duct (WD), the earliest embryonic epithelial progenitor of renal tubules, in the etiology of autosomal dominant polycystic kidney disease (ADPKD). ADPKD is associated with a germline mutation of one of the two Pkd1 alleles. For the disease to occur, a second event that disrupts the expression of the other inherited Pkd1 allele must occur. We postulated that this secondary event can occur in the pronephric WD. Using Cre-Lox recombination, mice with WD-specific deletion of one or both Pkd1 alleles were generated. Homozygous Pkd1-targeted deletion in WD-derived tissues resulted in mice with large cystic kidneys and serologic evidence of renal failure. In contrast, heterozygous deletion of Pkd1 in the WD led to kidneys that were phenotypically indistinguishable from control in the early postnatal period. High-throughput sequencing, however, revealed underlying gene and microRNA (miRNA) changes in these heterozygous mutant kidneys that suggest a strong predisposition toward developing ADPKD. Bioinformatic analysis of this data demonstrated an upregulation of several miRNAs that have been previously associated with PKD; pathway analysis further demonstrated that the differentially expressed genes in the heterozygous mutant kidneys were overrepresented in signaling pathways associated with maintenance and function of the renal tubular epithelium. These results suggest that the WD may be an early epithelial target for the genetic or molecular signals that can lead to cyst formation in ADPKD.
In this study, the pull-in phenomenon of a Nano-actuator is investigated employing a nonlocal Bernoulli-Euler beam model with clamped-clamped conditions. The model accounts for viscous damping, residual stresses, the van der Waals (vdW) force and electrostatic forces with nonlocal effects. The hybrid differential transformation/finite difference method (HDTFDM) is used to analyze the nonlocal effects on a graphene sheet nanobeam, which is electrostatically actuated under the influence of the coupling effect, the von Kármán nonlinear strains and the fringing field effect. The pull-in voltage as calculated by the presented model deviates by no more than 0.29% from previous literature, verifying the validity of the HDTFDM. Furthermore, the nonlocal nonlinear behavior of the electrostatically actuated nanobeam is investigated, and the effects of viscous damping, residual stresses, and length-gap ratio are examined in detail. Overall, the results reveal that small scale effects significantly influence the characteristics of the graphene sheet nanobeam actuator.
Adolescence is a period of heightened susceptibility to peer influences, and deviant peer affiliation has well-established implications for the development of psychopathology. However, little is known about the role of brain functions in pathways connecting peer contexts and health risk behaviors. We tested developmental cascade models to evaluate contributions of adolescent risk taking, peer influences, and neurobehavioral variables of risk processing and cognitive control to substance use among 167 adolescents who were assessed annually for four years. Risk taking at Time 1 was related to substance use at Time 4 indirectly through peer substance use at Time 2 and insular activation during risk processing at Time 3. Furthermore, neural cognitive control moderated these effects. Greater insular activation during risk processing was related to higher substance use for those with greater medial prefrontal cortex activation during cognitive control, but it was related to lower substance use among those with lower medial prefrontal cortex activation during cognitive control. Neural processes related to risk processing and cognitive control play a crucial role in the processes linking risk taking, peer substance use, and adolescents’ own substance use.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Antimicrobial stewardship programs typically use days of therapy to assess antimicrobial use. However, this metric does not account for the antimicrobial spectrum of activity. We applied an antibiotic spectrum index to a population of very-low-birth-weight infants to assess its utility to evaluate the impact of antimicrobial stewardship interventions.