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Arid and semi-arid regions of the world are particularly vulnerable to greenhouse gas-driven hydroclimate change. Climate models are our primary tool for projecting the future hydroclimate that society in these regions must adapt to, but here, we present a concerning discrepancy between observed and model-based historical hydroclimate trends. Over the arid/semi-arid regions of the world, the predominant signal in all model simulations is an increase in atmospheric water vapor, on average, over the last four decades, in association with the increased water vapor-holding capacity of a warmer atmosphere. In observations, this increase in atmospheric water vapor has not happened, suggesting that the availability of moisture to satisfy the increased atmospheric demand is lower in reality than in models in arid/semi-arid regions. This discrepancy is most clear in locations that are arid/semi-arid year round, but it is also apparent in more humid regions during the most arid months of the year. It indicates a major gap in our understanding and modeling capabilities which could have severe implications for hydroclimate projections, including fire hazard, moving forward.

Social interactions serve as the primary training ground for many of a child’s positive cognitive and developmental abilities. Parent responsiveness has been identified as one key mechanism through which children gain more mature skills, but the question of how children elicit responses from their parents remains to be fully investigated. In this study, we utilized head-mounted eye trackers to track moment-by-moment shifts in gaze, manual action, and speech during parent-child toy play. This allowed us to identify the moments preceding a parent response and the type and timing of the parent’s response relative to the child’s behaviors. We found that child events of attention and action – where they were both touching and looking at a toy – were more successful in eliciting parent responses overall and in eliciting multimodal parent responses than events of just child look or child touch. The parent’s latency to respond to their child differed by event type and duration, suggesting that child behaviors influence parent responses. Implications and future directions are discussed.

Sustained attention (SA) is a critical skill in which a child is able tomaintain visual attention to an object or stimulus. The current studyemploys head-mounted eye trackers to study the cognitive processesunderlying SA by analyzing micro-level behaviors during parent-child social interactions in both typically and atypically developingchildren. Specifically, we examined the role of parent look, parenttouch, and child touch on SA duration. Results show that parent lookequally influences SA in both groups, while parent touch is morecritical for SA for TD children and the child’s own touching is morecritical for SA in children with autism spectrum disorder (ASD).Implications of different pathways to maintain SA between typicallydeveloping children and children with ASD are discussed.

The Community Land Model (CLM) is the land component of the Community Earth System Model (CESM) and is used in several global and regional modeling systems. In this paper, we introduce model developments included in CLM version 5 (CLM5), which is the default land component for CESM2. We assess an ensemble of simulations, including prescribed and prognostic vegetation state, multiple forcing data sets, and CLM4, CLM4.5, and CLM5, against a range of metrics including from the International Land Model Benchmarking (ILAMBv2) package. CLM5 includes new and updated processes and parameterizations: (1) dynamic land units, (2) updated parameterizations and structure for hydrology and snow (spatially explicit soil depth, dry surface layer, revised groundwater scheme, revised canopy interception and canopy snow processes, updated fresh snow density, simple firn model, and Model for Scale Adaptive River Transport), (3) plant hydraulics and hydraulic redistribution, (4) revised nitrogen cycling (flexible leaf stoichiometry, leaf N optimization for photosynthesis, and carbon costs for plant nitrogen uptake), (5) global crop model with six crop types and time-evolving irrigated areas and fertilization rates, (6) updated urban building energy, (7) carbon isotopes, and (8) updated stomatal physiology. New optional features include demographically structured dynamic vegetation model (Functionally Assembled Terrestrial Ecosystem Simulator), ozone damage to plants, and fire trace gas emissions coupling to the atmosphere. Conclusive establishment of improvement or degradation of individual variables or metrics is challenged by forcing uncertainty, parametric uncertainty, and model structural complexity, but the multivariate metrics presented here suggest a general broad improvement from CLM4 to CLM5.

Visual disengagement has been hypothesized as an endophenotype for autism. In this study we used twin modelling to assess the role of genetics in basic measures of visual disengagement, and tested their putative association to autistic traits in the general population. We used the Gap Overlap task in a sample of 492 twins. Results showed that most of the covariance among eye movement latencies across conditions was shared and primarily genetic. Further, there were unique genetic contributions to the Gap condition, but not to the Overlap condition--i.e. the one theorized to capture visual disengagement. We found no phenotypic association between autistic traits and disengagement, thus not supporting the hypothesis of visual disengagement as an endophenotype for autistic traits.

Adolescents with autism often experience pronounced difficulties with social communication, and novel interventions designed to improve core abilities are greatly needed. This study examines if providing immediate video feedback, an extension of video self-modeling, can aid adolescents with autism to self-identify strengths and irregularities from their social interactions. Using multiple baseline design across four participants, individuals engaged in naturalistic conversations wearing video recording glasses. During the intervention, videos were reviewed immediately and participants recognized when they were not following typical social-communicative convention. Based on observational data coded from videos, all four participants modified their behavior during subsequent conversations. Although adolescents with autism may hypothetically know to behave, viewing themselves on video may provide practical cues to support social insight and behavioral change.

The second iteration of the Autism Brain Imaging Data Exchange (ABIDE II) aims to enhance the scope of brain connectomics research in Autism Spectrum Disorder (ASD). Consistent with the initial ABIDE effort (ABIDE I), that released 1112 datasets in 2012, this new multisite open-data resource is an aggregate of resting state functional magnetic resonance imaging (MRI) and corresponding structural MRI and phenotypic datasets. ABIDE II includes datasets from an additional 487 individuals with ASD and 557 controls previously collected across 16 international institutions. The combination of ABIDE I and ABIDE II provides investigators with 2156 unique cross-sectional datasets allowing selection of samples for discovery and/or replication. This sample size can also facilitate the identification of neurobiological subgroups, as well as preliminary examinations of sex differences in ASD. Additionally, ABIDE II includes a range of psychiatric variables to inform our understanding of the neural correlates of co-occurring psychopathology; 284 diffusion imaging datasets are also included. It is anticipated that these enhancements will contribute to unraveling key sources of ASD heterogeneity.

Low thermal-equilibrium nuclear spin polarizations and the need for sophisticated instrumentation render conventional nuclear magnetic resonance (NMR) spectroscopy and imaging (MRI) incompatible with small-scale microfluidic devices. Hyperpolarized 129Xe gas has found use in the study of many materials but has required very large and expensive instrumentation. Recently a microfabricated device with modest instrumentation demonstrated all-optical hyperpolarization and detection of 129Xe gas. This device was limited by 129Xe polarizations less than 1%, 129Xe NMR signals smaller than 20 nT, and transport of hyperpolarized 129Xe over millimeter lengths. Higher polarizations, versatile detection schemes, and flow of 129Xe over larger distances are desirable for wider applications. Here we demonstrate an ultra-sensitive microfabricated platform that achieves 129Xe polarizations reaching 7%, NMR signals exceeding 1 μT, lifetimes up to 6 s, and simultaneous two-mode detection, consisting of a high-sensitivity in situ channel with signal-to-noise of 105 and a lower-sensitivity ex situ detection channel which may be useful in a wider variety of conditions. 129Xe is hyperpolarized and detected in locations more than 1 cm apart. Our versatile device is an optimal platform for microfluidic magnetic resonance in particular, but equally attractive for wider nuclear spin applications benefitting from ultra-sensitive detection, long coherences, and simple instrumentation.

Autism spectrum disorder (ASD) is commonly conceived as the extreme end of a continuum. Research suggests that autistic individuals outperform typically developing controls in visual search. Thus, enhanced visual search may represent an adaptive trait associated with ASD. Here, using a large general population sample (N = 608, aged 9-14 years), we tested if higher levels of autistic traits are associated with enhanced visual search. Visual search was evaluated using both manual responses and eye movements, and autistic traits were measured using the Social Responsiveness Scale. Contrary to our hypothesis, no significant relation between autistic traits and visual search were observed. The theoretical implications of these results are discussed.

Atypical gaze patterns are a promising biomarker of autism spectrum disorder. To measure gaze accurately, however, it typically requires highly controlled studies in the laboratory using specialized equipment that is often expensive, thereby limiting the scalability of these approaches. Here we test whether a recently developed smartphone‐based gaze estimation method could overcome such limitations and take advantage of the ubiquity of smartphones. As a proof‐of‐principle, we measured gaze while a small sample of well‐assessed autistic participants and controls watched videos on a smartphone, both in the laboratory (with lab personnel) and in remote home settings (alone). We demonstrate that gaze data can be efficiently collected, in‐home and longitudinally by participants themselves, with sufficiently high accuracy (gaze estimation error below 1° visual angle on average) for quantitative, feature‐based analysis. Using this approach, we show that autistic individuals have reduced gaze time on human faces and longer gaze time on non‐social features in the background, thereby reproducing established findings in autism using just smartphones and no additional hardware. Our approach provides a foundation for scaling future research with larger and more representative participant groups at vastly reduced cost, also enabling better inclusion of underserved communities. Lay Summary: Atypical eye gaze is a promising biomarker of autism but generally requires controlled laboratory assessments with expensive eye trackers. Here we leveraged a recently developed smartphone‐based method that measures eye movements to overcome such challenges. The smartphone method reliably characterized reduced gaze onto human faces versus other non‐human backgrounds, while individuals watch videos on the phone screen, indicating promise for larger‐scale clinical and scientific studies of atypical eye gaze in autism. [ABSTRACT FROM AUTHOR]

Recent work has shown that xenon chemical shifts in cryptophane-cage sensors are affected when tethered chelators bind to metals. Here, we explore the xenon shifts in response to a wide range of metal ions binding to diastereomeric forms of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) linked to cryptophane-A. The shifts induced by the binding of Ca(2+) , Cu(2+) , Ce(3+) , Zn(2+) , Cd(2+) , Ni(2+) , Co(2+) , Cr(2+) , Fe(3+) , and Hg(2+) are distinct. In addition, the different responses of the diastereomers for the same metal ion indicate that shifts are affected by partial folding with a correlation between the expected coordination number of the metal in the DOTA complex and the chemical shift of (129) Xe. These sensors may be used to detect and quantify many important metal ions, and a better understanding of the basis for the induced shifts could enhance future designs.

Although gaze can be directed at any location, different locationsin the visual environment vary in terms of how likelythey are to draw another person’s attention. One could thereforeweigh incoming perceptual signals (e.g., eye cues) againstthis prior knowledge (the relative visual saliency of locationsin the scene) in order to infer the true target of another person’sgaze. This Bayesian approach to modeling gaze perception hasinformed computer vision techniques, but we assess whetherit is a good model for human performance. We present subjectswith a “gazer” fixating his eyes on various locations ona 2-dimensional surface, and project an arbitrary photographicimage onto that surface. Subjects judge where the gazer islooking in the image. A full Bayesian model, which takes imagesaliency information into account, fits subjects’ gaze judgmentsbetter than a reduced model that only considers the perceiveddirection of the gazer’s eyes.

The comprehension of dynamically unfolding social situations is made possible by the seamless integration of multimodal information merged with rich intuitions about the thoughts and behaviors of others. We examined how high-functioning adults with autism spectrum disorder and neurotypical controls made a complex social judgment (i.e. rating the social awkwardness of scenes from a television sitcom) across three conditions that manipulated presentation modality--visual alone, transcribed text alone, or visual and auditory together. The autism spectrum disorder and control groups collectively assigned similar mean awkwardness ratings to individual scenes. However, individual participants with autism spectrum disorder tended to respond more idiosyncratically than controls, assigning ratings that were less correlated with the ratings of the other participants in the sample. We found no evidence that this group difference was isolated to any specific presentation modality. In a comparison condition, we found no group differences when participants instead rated the happiness of characters (a more basic social judgment) in full audiovisual format. Thus, although we observed differences in the manner with which high-functioning adults with autism spectrum disorder make social judgments compared to controls, these group differences may be dependent on the social dimension being judged, rather than the specific modality of presentation.

Two-phase designs in epidemiological studies of autism prevalence introduce methodological complications that can severely limit the precision of resulting estimates. If the assumptions used to derive the prevalence estimate are invalid or if the uncertainty surrounding these assumptions is not properly accounted for in the statistical inference procedure, then the point estimate may be inaccurate and the confidence interval may not be a true reflection of the precision of the estimate. We examine these potential pitfalls in the context of a recent high-profile finding by Kim et al. (2011, Prevalence of autism spectrum disorders in a total population sample. "American Journal of Psychiatry" 168: 904-912), who estimated that autism spectrum disorder affects 2.64% of children in a South Korean community. We reconstructed the study's methodology and used Monte Carlo simulations to analyze whether their point estimate and 95% confidence interval (1.91%, 3.37%) were reasonable, given what was known about their screening instrument and sample. We find the original point estimate to be highly assumption-dependent, and after accounting for sources of uncertainty unaccounted for in the original article, we demonstrate that a more reasonable confidence interval would be approximately twice as large as originally reported. We argue that future studies should give serious consideration to the additional sources of uncertainty introduced by a two-phase design, which may easily outstrip any expected gains in efficiency.