Showing papers by "University of Massachusetts Boston published in 2015"

Mechanisms of stress in the brain

Abstract: The brain is the central organ involved in perceiving and adapting to social and physical stressors via multiple interacting mediators, from the cell surface to the cytoskeleton to epigenetic regulation and nongenomic mechanisms. A key result of stress is structural remodeling of neural architecture, which may be a sign of successful adaptation, whereas persistence of these changes when stress ends indicates failed resilience. Excitatory amino acids and glucocorticoids have key roles in these processes, along with a growing list of extra- and intracellular mediators that includes endocannabinoids and brain-derived neurotrophic factor (BDNF). The result is a continually changing pattern of gene expression mediated by epigenetic mechanisms involving histone modifications and CpG methylation and hydroxymethylation as well as by the activity of retrotransposons that may alter genomic stability. Elucidation of the underlying mechanisms of plasticity and vulnerability of the brain provides a basis for understanding the efficacy of interventions for anxiety and depressive disorders as well as age-related cognitive decline.

Biodiversity enhances ecosystem multifunctionality across trophic levels and habitats

Abstract: The importance of biodiversity for the integrated functioning of ecosystems remains unclear because most evidence comes from analyses of biodiversity's effect on individual functions. Here we show that the effects of biodiversity on ecosystem function become more important as more functions are considered. We present the first systematic investigation of biodiversity's effect on ecosystem multifunctionality across multiple taxa, trophic levels and habitats using a comprehensive database of 94 manipulations of species richness. We show that species-rich communities maintained multiple functions at higher levels than depauperate ones. These effects were stronger for herbivore biodiversity than for plant biodiversity, and were remarkably consistent across aquatic and terrestrial habitats. Despite observed tradeoffs, the overall effect of biodiversity on multifunctionality grew stronger as more functions were considered. These results indicate that prior research has underestimated the importance of biodiversity for ecosystem functioning by focusing on individual functions and taxonomic groups.

Early Intervention for Children With Autism Spectrum Disorder Under 3 Years of Age: Recommendations for Practice and Research

Abstract: This article reviews current evidence for autism spectrum disorder (ASD) interventions for children aged <3 years, based on peer-reviewed articles published up to December 2013. Several groups have adapted treatments initially designed for older, preschool-aged children with ASD, integrating best practice in behavioral teaching methods into a developmental framework based on current scientific understanding of how infants and toddlers learn. The central role of parents has been emphasized, and interventions are designed to incorporate learning opportunities into everyday activities, capitalize on "teachable moments," and facilitate the generalization of skills beyond the familiar home setting. Our review identified several comprehensive and targeted treatment models with evidence of clear benefits. Although some trials were limited to 8- to 12-week outcome data, enhanced outcomes associated with some interventions were evaluated over periods as long as 2 years. Based on this review, recommendations are proposed for clinical practice and future research.

Aluminum Plasmonic Multicolor Meta-Hologram

Abstract: We report a phase-modulated multicolor meta-hologram (MCMH) that is polarization-dependent and capable of producing images in three primary colors. The MCMH structure is made of aluminum nanorods that are arranged in a two-dimensional array of pixels with surface plasmon resonances in red, green, and blue. The aluminum nanorod array is patterned on a 30 nm thick SiO2 spacer layer sputtered on top of a 130 nm thick aluminum mirror. With proper design of the structure, we obtain resonances of narrow bandwidths to allow for implementation of the multicolor scheme. Taking into account of the wavelength dependence of the diffraction angle, we can project images to specific locations with predetermined size and order. With tuning of aluminum nanorod size, we demonstrate that the image color can be continuously varied across the visible spectrum.

A Longitudinal Study of Electronic Cigarette Use Among a Population-Based Sample of Adult Smokers: Association With Smoking Cessation and Motivation to Quit

Abstract: Aims: Increasingly popular electronic cigarettes (e-cigarettes) may be the most promising development yet to end cigarette smoking. However, there is sparse evidence that their use promotes cessation. We investigated whether e-cigarette use increases smoking cessation and/or has a deleterious effect on quitting smoking and motivation to quit.

Early Identification of Autism Spectrum Disorder: Recommendations for Practice and Research.

Abstract: Early identification of autism spectrum disorder (ASD) is essential to ensure that children can access specialized evidence-based interventions that can help to optimize long-term outcomes. Early identification also helps shorten the stressful "diagnostic odyssey" that many families experience before diagnosis. There have been important advances in research into the early development of ASDs, incorporating prospective designs and new technologies aimed at more precisely delineating the early emergence of ASD. Thus, an updated review of the state of the science of early identification of ASD was needed to inform best practice. These issues were the focus of a multidisciplinary panel of clinical practitioners and researchers who completed a literature review and reached consensus on current evidence addressing the question "What are the earliest signs and symptoms of ASD in children aged ≤24 months that can be used for early identification?" Summary statements address current knowledge on early signs of ASD, potential contributions and limitations of prospective research with high-risk infants, and priorities for promoting the incorporation of this knowledge into clinical practice and future research.

How Does IT Ambidexterity Impact Organizational Agility

Abstract: Organizational agility is a significant business capability. Though there have been numerous studies about the effects of information technology IT capabilities on organizational agility, there has been limited attention on the enabling effects of IT ambidexterity, namely, the dual capacity to explore and exploit IT resources and practices. We propose that IT ambidexterity enhances organizational agility by facilitating operational ambidexterity, and that the magnitude of facilitation depends on the level of environmental dynamism. We test these relationships utilizing data from a large-scale, matched-pair field survey of business and IT executives. The results confirm that a firm's IT ambidexterity does enhance its organizational agility through the mediated effects of operational ambidexterity, and that the dynamism of a firm's environment affects these relationships.

Mindfulness and emotion regulation

Abstract: One proposed pathway for the documented psychological effects of mindfulness (cultivating awareness and acceptance of the present moment) has been through its facilitation of adaptive emotion regulation (ER). Although conceptual overlap between the two constructs complicates interpretation of correlational findings, an emerging body of laboratory, experimental, and treatment outcome studies provides preliminary support of proposed conceptual models. These findings indicate that the practice of mindfulness is associated with healthy ER (e.g., reduced intensity of distress, enhanced emotional recovery, reduced negative self-referential processing, and/or enhanced ability to engage in goal-directed behaviors) and may play a causal role in these effects. More experimental and longitudinal research is needed to determine the exact nature, temporal unfolding, and causality of these associations.

Early Screening of Autism Spectrum Disorder: Recommendations for Practice and Research

Abstract: This article reviews current evidence for autism spectrum disorder (ASD) screening based on peer-reviewed articles published to December 2013. Screening provides a standardized process to ensure that children are systematically monitored for early signs of ASD to promote earlier diagnosis. The current review indicates that screening in children aged 18 to 24 months can assist in early detection, consistent with current American Academy of Pediatrics' recommendations. We identify ASD-specific and broadband screening tools that have been evaluated in large community samples which show particular promise in terms of accurate classification and clinical utility. We also suggest strategies to help overcome challenges to implementing ASD screening in community practice, as well as priorities for future research.

Message framing in green advertising: the effect of construal level and consumer environmental concern

Abstract: Many firms adopt green advertising and put great emphasis on the value of green marketing strategies. However, little research has examined the effectiveness of green appeal in advertisements. Building on message framing and construal level theory, this study examines the moderating role of temporal distance in effects of gain or loss framed messages on consumers' attitudes and purchase intentions towards advertised brand. The findings demonstrate that a congruency between loss frame and low level construal, as well as the match between gain frame and high level construal, leads to more positive outcomes in consumers' attitudes and purchase intention. Furthermore, this research reveals that salience of the congruency effect varies in line with the level of consumer environmental concern, which has important theoretical and practical implications.

Marine biodiversity and ecosystem functioning: What's known and what's next?

Abstract: Marine ecosystems are experiencing rapid and pervasive changes in biodiversity and species composition. Understanding the ecosystem consequences of these changes is critical to effectively managing these systems. Over the last several years, numerous experimental manipulations of species richness have been performed, yet existing quantitative syntheses have focused on a just a subset of processes measured in experiments and, as such, have not summarized the full data available from marine systems. Here, we present the results of a meta-analysis of 110 marine experiments from 42 studies that manipulated the species richness of organisms across a range of taxa and trophic levels and analysed the consequences for various ecosystem processes (categorised as production, consumption or biogeochemical fluxes). Our results show that, generally, mixtures of species tend to enhance levels of ecosystem function relative to the average component species in monoculture, but have no effect or a negative effect on functioning relative to the ‘highest- performing’ species. These results are largely consistent with those from other syntheses, and extend conclusions to ecological functions that are commonly measured in the marine realm (e.g. nutrient release from sediment bioturbation). For experiments that manipulated three or more levels of richness, we attempted to discern the functional form of the biodiversity–ecosystem functioning relationship. We found that, for response variables related to consumption, a power-function best described the relationship, which is also consistent with previous findings. However, we identified a linear relationship between richness and production. Combined, our results suggest that changes in the number of species will, on average, tend to alter the functioning of marine ecosystems. We outline several research frontiers that will allow us to more fully understand how, why, and when diversity may drive the functioning of marine ecosystems. Synthesis The oceans host an incredible number and variety of species. However, human activities are driving rapid changes in the marine environment. It is imperative we understand ecosystem consequences of any associated loss of species. We summarized data from 110 experiments that manipulated species diversity and evaluated resulting changes to a range of ecosystem responses. We show that losing species, on average, decreases productivity, growth, and a myriad of other processes related to how marine organisms capture and utilize resources. Finally, we suggest that the loss of species may have stronger consequences for some processes than others.

Are women really more risk‐averse than men? a re‐analysis of the literature using expanded methods

Abstract: While a substantial literature in economics and finance has concluded that ‘women are more risk averse than men’, this conclusion merits investigation. After briefly clarifying the difference between making generalizations about groups, on the one hand, and making valid inferences from samples, on the other, this essay suggests improvements to how economists communicate our research results. Supplementing findings of statistical significance with quantitative measures of both substantive difference (Cohen's d, a measure in common use in non-Economics literatures) and of substantive overlap (the Index of Similarity, newly proposed here) adds important nuance to the discussion of sex differences. These measures are computed from the data on men, women and risk used in 35 scholarly works from economics, finance and decision science. The results are considerably more mixed and overlapping than would commonly be inferred from the broad claims made in the literature, with standardized differences in means mostly amounting to considerably less than one standard deviation, and the degree of overlap between male and female distributions generally exceeding 80%. In addition, studies that look at contextual influences suggest that these contribute importantly to observations of differences both between and within the sexes.

Spontaneous Gamma Activity in Schizophrenia.

Abstract: Importance A major goal of translational neuroscience is to identify neural circuit abnormalities in neuropsychiatric disorders that can be studied in animal models to facilitate the development of new treatments. Oscillations in the gamma band (30-100 Hz) of the electroencephalogram have received considerable interest as the basic mechanisms underlying these oscillations are understood, and gamma abnormalities have been found in schizophrenia (SZ). Animal models of SZ based on hypofunction of the N -methyl-d-aspartate receptor (NMDAR) demonstrate increased spontaneous broadband gamma power, but this phenomenon has not been identified clearly in patients with SZ. Objective To examine spontaneous gamma power and its relationship to evoked gamma oscillations in the auditory cortex of patients with SZ. Design, Setting, and Participants We performed a cross-sectional study including 24 patients with chronic SZ and 24 matched healthy control participants at the Veterans Affairs Boston Healthcare System from January 1, 2009, through December 31, 2012. Electroencephalograms were obtained during auditory steady-state stimulation at multiple frequencies (20, 30, and 40 Hz) and during a resting state in 18 participants in each group. Main Outcomes and Measures Electroencephalographic activity in the auditory cortex was estimated using dipole source localization. Auditory steady-state response (ASSR) measures included the phase-locking factor and evoked power. Spontaneous gamma power was measured as induced (non–phase-locked) gamma power in the ASSR data and as total gamma power in the resting-state data. Results The ASSR phase-locking factor was reduced significantly in patients with SZ compared with controls for the 40-Hz stimulation (mean [SD], 0.075 [0.028] vs 0.113 [0.065]; F 1,46 = 6.79 [ P = .012]) but not the 20- or the 30-Hz stimulation (0.042 [0.038] vs 0.043 [0.034]; F 1,46 = 0.006 [ P = .938] and 0.084 [0.040] vs 0.098 [0.050]; F 1,46 = 1.605 [ P = .212], respectively), repeating previous findings. The mean [SD] broadband-induced (30-100 Hz) gamma power was increased in patients with SZ compared with controls during steady-state stimulation (6.579 [3.783] vs 3.984 [1.843]; F 1,46 = 9.128 [ P = .004]; d = 0.87) but not during rest (0.006 [0.003] vs 0.005 [0.002]; F 1,34 = 1.067 [ P = .309]; d = 0.35). Induced gamma power in the left hemisphere of the patients with SZ during the 40-Hz stimulation was positively correlated with auditory hallucination symptoms (tangential, ρ = 0.587 [ P = .031]; radial, ρ = 0.593 [ P = .024]) and negatively correlated with the ASSR phase-locking factor (baseline: ρ = −0.572 [ P = .024]; ASSR: ρ = −0.568 [ P = .032]). Conclusions and Relevance Spontaneous gamma activity is increased during auditory steady-state stimulation in SZ, reflecting a disruption in the normal balance of excitation and inhibition. This phenomenon interacts with evoked oscillations, possibly contributing to the gamma ASSR deficit found in SZ. The similarity of increased spontaneous gamma power in SZ to the findings of increased spontaneous gamma power in animal models of NMDAR hypofunction suggests that spontaneous gamma power could serve as a biomarker for the integrity of NMDARs on parvalbumin-expressing inhibitory interneurons in humans and in animal models of neuropsychiatric disorders.

Using fuzzy cognitive mapping as a participatory approach to analyze change, preferred states, and perceived resilience of social-ecological systems

Abstract: There is a growing interest in the use of fuzzy cognitive mapping (FCM) as a participatory method for understanding social-ecological systems (SESs). In recent years, FCM has been used in a diverse set of contexts ranging from fisheries management to agricultural development, in an effort to generate transparent graphical models of complex systems that are useful for decision making, illuminate the core presumptions of environmental stakeholders, and structure environmental problems for scenario development. This increase in popularity is because of FCM’s bottom-up approach and its ability to incorporate a range of individual, community-level, and expert knowledge into an accessible and standardized format. Although there has been an increase in the use of FCM as an environmental planning and learning tool, limited progress has been made with regard to the method’s relationship to existing resilience frameworks and how the use of FCM compares with other participatory modeling/approaches available. Using case study data developed from community-driven models of the bushmeat trade in Tanzania, we examine the usefulness of FCM for promoting resilience analysis among stakeholders in terms of identifying key state variables that comprise an SES, evaluating alternative SES equilibrium states, and defining desirable or undesirable state outcomes through scenario analysis.

Secular trends in moderate-to-vigorous physical activity in 32 countries from 2002 to 2010: a cross-national perspective

Abstract: Background: Sufficient levels of moderate to vigorous physical activity (MVPA) give substantial health benefits to adolescents. This article examines trends in physical activity (PA) from 2002 to 2010 across 32 countries from Europe and North America. Methods: Representative samples included 479 674 pupils (49% boys) aged 11 years ( n = 156 383), 13 years ( n = 163 729) and 15 years ( n = 159 562). The trends in meeting the recommendations for PA (at least 60 min daily) were evaluated using logistic regression. Results: There was a slight overall increase between 2002 and 2010 (17.0% and 18.6%, respectively). MVPA increased significantly ( P ≤ 0.05) among boys in 16 countries. Conversely, nine countries showed a significant decrease. Among girls, 10 countries showed a significant increase ( P ≤ 0.05). Eight countries showed a significant decrease. For all countries combined, girls were slightly less likely to show an increase in PA over time. Conclusions: The majority of adolescents do not meet current recommendations of PA. Further investment at national and international levels is therefore necessary to increase PA participation among children and adolescents and reduce the future health burden associated with inactivity.

Transcriptional Bursting in Gene Expression: Analytical Results for General Stochastic Models.

Abstract: Gene expression in individual cells is highly variable and sporadic, often resulting in the synthesis of mRNAs and proteins in bursts. Such bursting has important consequences for cell-fate decisions in diverse processes ranging from HIV-1 viral infections to stem-cell differentiation. It is generally assumed that bursts are geometrically distributed and that they arrive according to a Poisson process. On the other hand, recent single-cell experiments provide evidence for complex burst arrival processes, highlighting the need for analysis of more general stochastic models. To address this issue, we invoke a mapping between general stochastic models of gene expression and systems studied in queueing theory to derive exact analytical expressions for the moments associated with mRNA/protein steady-state distributions. These results are then used to derive noise signatures, i.e. explicit conditions based entirely on experimentally measurable quantities, that determine if the burst distributions deviate from the geometric distribution or if burst arrival deviates from a Poisson process. For non-Poisson arrivals, we develop approaches for accurate estimation of burst parameters. The proposed approaches can lead to new insights into transcriptional bursting based on measurements of steady-state mRNA/protein distributions.

Topographical Mapping of the Rainbow Trout (Oncorhynchus mykiss) Microbiome Reveals a Diverse Bacterial Community with Antifungal Properties in the Skin

Abstract: The mucosal surfaces of wild and farmed aquatic vertebrates face the threat of many aquatic pathogens, including fungi. These surfaces are colonized by diverse symbiotic bacterial communities that may contribute to fight infection. Whereas the gut microbiome of teleosts has been extensively studied using pyrosequencing, this tool has rarely been employed to study the compositions of the bacterial communities present on other teleost mucosal surfaces. Here we provide a topographical map of the mucosal microbiome of an aquatic vertebrate, the rainbow trout (Oncorhynchus mykiss). Using 16S rRNA pyrosequencing, we revealed novel bacterial diversity at each of the five body sites sampled and showed that body site is a strong predictor of community composition. The skin exhibited the highest diversity, followed by the olfactory organ, gills, and gut. Flectobacillus was highly represented within skin and gill communities. Principal coordinate analysis and plots revealed clustering of external sites apart from internal sites. A highly diverse community was present within the epithelium, as demonstrated by confocal microscopy and pyrosequencing. Using in vitro assays, we demonstrated that two Arthrobacter sp. skin isolates, a Psychrobacter sp. strain, and a combined skin aerobic bacterial sample inhibit the growth of Saprolegnia australis and Mucor hiemalis, two important aquatic fungal pathogens. These results underscore the importance of symbiotic bacterial communities of fish and their potential role for the control of aquatic fungal diseases.

Uvudf: ultraviolet through near-infrared catalog and photometric redshifts of galaxies in the hubble ultra deep field

Abstract: We present photometry and derived redshifts from up to eleven bandpasses for 9927 galaxies in the Hubble Ultra Deep field (UDF), covering an observed wavelength range from the near-ultraviolet (NUV) to the near-infrared (NIR) with Hubble Space Telescope observations. Our Wide Field Camera 3 (WFC3)/UV F225W, F275W, and F336W image mosaics from the ultra-violet UDF (UVUDF) imaging campaign are newly calibrated to correct for charge transfer inefficiency, and use new dark calibrations to minimize background gradients and pattern noise. Our NIR WFC3/IR image mosaics combine the imaging from the UDF09 and UDF12 campaigns with CANDELS data to provide NIR coverage for the entire UDF field of view. We use aperture-matched point-spread function corrected photometry to measure photometric redshifts in the UDF, sampling both the Lyman break and Balmer break of galaxies at z ~ 0.8-3.4, and one of the breaks over the rest of the redshift range. Our comparison of these results with a compilation of robust spectroscopic redshifts shows an improvement in the galaxy photometric redshifts by a factor of two in scatter and a factor three in outlier fraction (OLF) over previous UDF catalogs. The inclusion of the new NUV data is responsible for a factor of two decrease in the OLF compared to redshifts determined from only the optical and NIR data, and improves the scatter at z 2. The panchromatic coverage of the UDF from the NUV through the NIR yields robust photometric redshifts of the UDF, with the lowest OLF available.

Terrestrial Laser Scanning for Plot-Scale Forest Measurement

Abstract: Plot-scale measurements have been the foundation for forest surveys and reporting for over 200 years. Through recent integration with airborne and satellite remote sensing, manual measurements of vegetation structure at the plot scale are now the basis for landscape, continental and international mapping of our forest resources. The use of terrestrial laser scanning (TLS) for plot-scale measurement was first demonstrated over a decade ago, with the intimation that these instruments could replace manual measurement methods. This has not yet been the case, despite the unparalleled structural information that TLS can capture. For TLS to reach its full potential, these instruments cannot be viewed as a logical progression of existing plot-based measurement. TLS must be viewed as a disruptive technology that requires a rethink of vegetation surveys and their application across a wide range of disciplines. We review the development of TLS as a plot-scale measurement tool, including the evolution of both instrument hardware and key data processing methodologies. We highlight two broad data modelling approaches of gap probability and geometrical modelling and the basic theory that underpins these. Finally, we discuss the future prospects for increasing the utilisation of TLS for plot-scale forest assessment and forest monitoring.

Between a Gay and a Straight Place: Bisexual Individuals’ Experiences with Monosexism

Abstract: Bisexual people experience monosexism, the privileging of sexual attraction to one sex or gender, from heterosexual, gay, and lesbian communities. The current study of 745 bisexual-identified participants explored their experiences of monosexism with heterosexual family members, heterosexual friends, gay family members, and gay friends. Results indicated that bisexual individuals reported significantly more discrimination from the heterosexual community in comparison to the gay or lesbian community, although the effect size was small. Acceptance of bisexuality from family and acceptance of bisexuality from friends were negative predictors of antibisexual discrimination. Clinical and research implications are discussed.

Measurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central d+Au collisions at sNN=200 GeV

Abstract: We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sqrt[s_{NN}]=200 GeV. The charged hadron is measured at midrapidity |η| 2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v_{2} for inclusive charged hadrons at midrapidity up to p_{T}=4.5 GeV/c. We also present the measurement of v_{2} for identified π^{±} and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sqrt[s_{NN}]=5.02 TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.

Better knowledge with social media? Exploring the roles of social capital and organizational knowledge management

Abstract: Purpose – The purpose of this paper is to explore social media’s impact on organizational knowledge quality through the theoretical lens of social capital and resource exchange. Design/methodology/approach – This is a theory-confirming, quantitative study using panel data collected through a Web-based survey. Findings – The results show that while social media affects structural capital and cognitive capital directly, it only affects relational capital indirectly through structural and cognitive capital. Moreover, overall social media and the enhanced social capital do help promote organizational efforts in knowledge management, which subsequently leads to a higher level of organizational knowledge quality. Research limitations/implications – All survey respondents were from the USA, which may limit the generalizability of the findings. The authors also call for more research in establishing the time sequence in the proposed causal relations and in the individual-level mechanism through which social media...

Early sex differences are not autism-specific: A Baby Siblings Research Consortium (BSRC) study

Abstract: The increased male prevalence of autism spectrum disorder (ASD) may be mirrored by the early emergence of sex differences in ASD symptoms and cognitive functioning. The female protective effect hypothesis posits that ASD recurrence and symptoms will be higher among relatives of female probands. This study examined sex differences and sex of proband differences in ASD outcome and in the development of ASD symptoms and cognitive functioning among the high-risk younger siblings of ASD probands and low-risk children. Prior to 18 months of age, 1824 infants (1241 high-risk siblings, 583 low-risk) from 15 sites were recruited. Hierarchical generalized linear model (HGLM) analyses of younger sibling and proband sex differences in ASD recurrence among high-risk siblings were followed by HGLM analyses of sex differences and group differences (high-risk ASD, high-risk non-ASD, and low-risk) on the Mullen Scales of Early Learning (MSEL) subscales (Expressive and Receptive Language, Fine Motor, and Visual Reception) at 18, 24, and 36 months and Autism Diagnostic Observation Schedule (ADOS) domain scores (social affect (SA) and restricted and repetitive behaviors (RRB)) at 24 and 36 months. Of 1241 high-risk siblings, 252 had ASD outcomes. Male recurrence was 26.7 % and female recurrence 10.3 %, with a 3.18 odds ratio. The HR-ASD group had lower MSEL subscale scores and higher RRB and SA scores than the HR non-ASD group, which had lower MSEL subscale scores and higher RRB scores than the LR group. Regardless of group, males obtained lower MSEL subscale scores, and higher ADOS RRB scores, than females. There were, however, no significant interactions between sex and group on either the MSEL or ADOS. Proband sex did not affect ASD outcome, MSEL subscale, or ADOS domain scores. A 3.2:1 male:female odds ratio emerged among a large sample of prospectively followed high-risk siblings. Sex differences in cognitive performance and repetitive behaviors were apparent not only in high-risk children with ASD, but also in high-risk children without ASD and in low-risk children. Sex differences in young children with ASD do not appear to be ASD-specific but instead reflect typically occurring sex differences seen in children without ASD. Results did not support a female protective effect hypothesis.