56 research outputs found

    Quantified Uncertainty in Thermodynamic Modeling for Materials Design

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    Phase fractions, compositions and energies of the stable phases as a function of macroscopic composition, temperature, and pressure (X-T-P) are the principle correlations needed for the design of new materials and improvement of existing materials. They are the outcomes of thermodynamic modeling based on the CALculation of PHAse Diagrams (CALPHAD) approach. The accuracy of CALPHAD predictions vary widely in X-T-P space due to experimental error, model inadequacy and unequal data coverage. In response, researchers have developed frameworks to quantify the uncertainty of thermodynamic property model parameters and propagate it to phase diagram predictions. In previous studies, uncertainty was represented as intervals on phase boundaries (with respect to composition) or invariant reactions (with respect to temperature) and was unable to represent the uncertainty in eutectoid reactions or in the stability of phase regions. In this work, we propose a suite of tools that leverages samples from the multivariate model parameter distribution to represent uncertainty in forms that surpass previous limitations and are well suited to materials design. These representations include the distribution of phase diagrams and their features, as well as the dependence of phase stability and the distributions of phase fraction, composition activity and Gibbs energy on X-T-P location - irrespective of the total number of components. Most critically, the new methodology allows the material designer to interrogate a certain composition and temperature domain and get in return the probability of different phases to be stable, which can positively impact materials design

    Rethinking Pen Input Interaction: Enabling Freehand Sketching Through Improved Primitive Recognition

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    Online sketch recognition uses machine learning and artificial intelligence techniques to interpret markings made by users via an electronic stylus or pen. The goal of sketch recognition is to understand the intention and meaning of a particular user's drawing. Diagramming applications have been the primary beneficiaries of sketch recognition technology, as it is commonplace for the users of these tools to rst create a rough sketch of a diagram on paper before translating it into a machine understandable model, using computer-aided design tools, which can then be used to perform simulations or other meaningful tasks. Traditional methods for performing sketch recognition can be broken down into three distinct categories: appearance-based, gesture-based, and geometric-based. Although each approach has its advantages and disadvantages, geometric-based methods have proven to be the most generalizable for multi-domain recognition. Tools, such as the LADDER symbol description language, have shown to be capable of recognizing sketches from over 30 different domains using generalizable, geometric techniques. The LADDER system is limited, however, in the fact that it uses a low-level recognizer that supports only a few primitive shapes, the building blocks for describing higher-level symbols. Systems which support a larger number of primitive shapes have been shown to have questionable accuracies as the number of primitives increase, or they place constraints on how users must input shapes (e.g. circles can only be drawn in a clockwise motion; rectangles must be drawn starting at the top-left corner). This dissertation allows for a significant growth in the possibility of free-sketch recognition systems, those which place little to no drawing constraints on users. In this dissertation, we describe multiple techniques to recognize upwards of 18 primitive shapes while maintaining high accuracy. We also provide methods for producing confidence values and generating multiple interpretations, and explore the difficulties of recognizing multi-stroke primitives. In addition, we show the need for a standardized data repository for sketch recognition algorithm testing and propose SOUSA (sketch-based online user study application), our online system for performing and sharing user study sketch data. Finally, we will show how the principles we have learned through our work extend to other domains, including activity recognition using trained hand posture cues

    Quantified Uncertainty in Thermodynamic Modeling for Materials Design

    Get PDF
    Phase fractions, compositions and energies of the stable phases as a function of macroscopic composition, temperature, and pressure (X-T-P) are the principle correlations needed for the design of new materials and improvement of existing materials. They are the outcomes of thermodynamic modeling based on the CALculation of PHAse Diagrams (CALPHAD) approach. The accuracy of CALPHAD predictions vary widely in X-T-P space due to experimental error, model inadequacy and unequal data coverage. In response, researchers have developed frameworks to quantify the uncertainty of thermodynamic property model parameters and propagate it to phase diagram predictions. In most previous studies, uncertainty was represented as intervals on phase boundaries (with respect to composition or temperature) and was unable to represent the uncertainty in invariant reactions or in the stability of phase regions. In this work, we propose a suite of tools that leverages samples from the multivariate model parameter distribution to represent uncertainty in forms that surpass previous limitations and are well suited to materials design. These representations include the distribution of phase diagrams and their features, as well as the dependence of phase stability and the distributions of phase fraction, composition, activity and Gibbs energy on X-T-P location - irrespective of the total number of components. Most critically, the new methodology allows the material designer to interrogate a certain composition and temperature domain and get in return the probability of different phases to be stable, which can positively impact materials design

    A Dominantly Inherited Progressive Deafness Affecting Distal Auditory Nerve and Hair Cells

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    We have studied 72 members belonging to a large kindred with a hearing disorder inherited in an autosomal dominant pattern. We used audiological, physiological, and psychoacoustic measures to characterize the hearing disorders. The initial phenotypic features of the hearing loss are of an auditory neuropathy (AN) with abnormal auditory nerve and brainstem responses (ABRs) and normal outer hair cell functions [otoacoustic emissions (OAEs) and cochlear microphonics (CMs)]. Psychoacoustic studies revealed profound abnormalities of auditory temporal processes (gap detection, amplitude modulation detection, speech discrimination) and frequency processes (difference limens) beyond that seen in hearing impairment accompanying cochlear sensory disorders. The hearing loss progresses over 10–20 years to also involve outer hair cells, producing a profound sensorineural hearing loss with absent ABRs and OAEs. Affected family members do not have evidence of other cranial or peripheral neuropathies. There was a marked improvement of auditory functions in three affected family members studied after cochlear implantation with return of electrically evoked auditory brainstem responses (EABRs), auditory temporal processes, and speech recognition. These findings are compatible with a distal auditory nerve disorder affecting one or all of the components in the auditory periphery including terminal auditory nerve dendrites, inner hair cells, and the synapses between inner hair cells and auditory nerve. There is relative sparing of auditory ganglion cells and their axons.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41385/1/10162_2004_Article_5014.pd

    Associations between rapid auditory processing of speech sounds and specific verbal communication skills in autism

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    IntroductionThe ability to rapidly process speech sounds is integral not only for processing other’s speech, but also for auditory processing of one’s own speech, which allows for maintenance of speech accuracy. Deficits in rapid auditory processing have been demonstrated in autistic individuals, particularly those with language impairment. We examined rapid auditory processing for speech sounds in relation to performance on a battery of verbal communication measures to determine which aspects of verbal communication were associated with cortical auditory processing in a sample of individuals with autism.MethodsParticipants were 57 children and adolescents (40 male and 17 female) ages 5–18 who were diagnosed with an Autism Spectrum Disorder (ASD). Rapid auditory processing of speech sounds was measured via a magnetoencephalographic (MEG) index of the quality of the auditory evoked response to the second of two differing speech sounds (“Ga” / “Da”) presented in rapid succession. Verbal communication abilities were assessed on standardized clinical measures of overall expressive and receptive language, vocabulary, articulation, and phonological processing. Associations between cortical measures of left- and right-hemisphere rapid auditory processing and verbal communication measures were examined.ResultsRapid auditory processing of speech sounds was significantly associated with speech articulation bilaterally (r = 0.463, p = 0.001 for left hemisphere and r = 0.328, p = 0.020 for right hemisphere). In addition, rapid auditory processing in the left hemisphere was significantly associated with overall expressive language abilities (r = 0.354, p = 0.013); expressive (r = 0.384, p = 0.005) vocabulary; and phonological memory (r = 0.325, p = 0.024). Phonological memory was found to mediate the relationship between rapid cortical processing and receptive language.DiscussionThese results demonstrate that impaired rapid auditory processing for speech sounds is associated with dysfunction in verbal communication in ASD. The data also indicate that intact rapid auditory processing may be necessary for even basic communication skills that support speech production, such as phonological memory and articulatory control

    Highly pathogenic avian influenza virus infection in chickens but not ducks is associated with elevated host immune and pro-inflammatory responses

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    Highly pathogenic avian influenza (HPAI) H5N1 viruses cause severe infection in chickens at near complete mortality, but corresponding infection in ducks is typically mild or asymptomatic. To understand the underlying molecular differences in host response, primary chicken and duck lung cells, infected with two HPAI H5N1 viruses and a low pathogenicity avian influenza (LPAI) H2N3 virus, were subjected to RNA expression profiling. Chicken cells but not duck cells showed highly elevated immune and pro-inflammatory responses following HPAI virus infection. HPAI H5N1 virus challenge studies in chickens and ducks corroborated the in vitro findings. To try to determine the underlying mechanisms, we investigated the role of signal transducer and activator of transcription-3 (STAT-3) in mediating pro-inflammatory response to HPAIV infection in chicken and duck cells. We found that STAT-3 expression was down-regulated in chickens but was up-regulated or unaffected in ducks in vitro and in vivo following H5N1 virus infection. Low basal STAT-3 expression in chicken cells was completely inhibited by H5N1 virus infection. By contrast, constitutively active STAT-3 detected in duck cells was unaffected by H5N1 virus infection. Transient constitutively-active STAT-3 transfection in chicken cells significantly reduced pro-inflammatory response to H5N1 virus infection; on the other hand, chemical inhibition of STAT-3 activation in duck cells increased pro-inflammatory gene expression following H5N1 virus infection. Collectively, we propose that elevated pro-inflammatory response in chickens is a major pathogenicity factor of HPAI H5N1 virus infection, mediated in part by the inhibition of STAT-3

    Preventing and Treating Women’s Postpartum Depression: A Qualitative Systematic Review on Partner-Inclusive Interventions

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    Partner-related factors associated with the occurrence of Postpartum Depression (PPD) may justify the partner’s inclusion in preventive and treatment approaches. The aim of this qualitative systematic review was to synthesize the literature on partner-inclusive interventions designed to prevent or treat postpartum depression (PPD) in women. In accordance with the PRISMA guidelines, the systematic search of studies published between 1967 and May 2015 in PsycINFO and PubMed identified 26 studies that met the inclusion criteria, which reported on 24 interventions. The following partner parameters were analyzed: participation type, session content, mental health assessment, attendance assessment, and the effects of partner’s participation on the women’s response to the interventions. Total participation by the partner was mostly reported in the prevention studies, whereas partial participation was reported in the treatment studies. The session content was mostly based on psychoeducation about PPD and parenthood, coping strategies to facilitate the transition to parenthood such as the partner’s emotional and instrumental support, and problem-solving and communication skills. Some benefits perceived by the couples underscore the relevance of the partner’s inclusion in PPD interventions. However, the scarce information about the partner’s attendance and the associated effects on the women’s intervention outcomes, along with methodological limitations of the studies, made it difficult to determine if the partner’s participation was associated with the intervention’s efficacy. Conclusions about the clinical value of including partners in PPD interventions are still limited. More research is warranted to better inform health policy strategies

    ‘It doesn’t reveal itself’: erosion and collapse of the image in contemporary visual practice

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    The article explores the extent to which ‘pictorial art’ resists legibility, transparency and coherence. The analysis of three artistic case studies, Idris Khan, Maria Chevska and Jane and Louise Wilson, serves to investigate established hierarchies in our perception of visual referents. In the discussion, the article inquires the means of erosion, veiling and dissemblance as ways to critique assumption of the homogeneity of the image. All artists cast a view of the external world by diverting it, defacing it and distancing themselves from the external environment. However, the distancing is never disconnected from the everyday and never succumbs to abstraction. The article argues that the crisis of the image offers a productive framework that allows artists to draw attention to the absence of logical structure and the instability of the visual sign

    Ex Situ Analyses of Non-Native Species Impacts on Imperiled Desert Fishes

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    This thesis focuses on interactions between two invasive species, the western mosquitofish (Gambusia affinis) and the red swamp crayfish (Procambarus clarkii), and two desert fishes, the Amargosa pupfish (Cyprinodon nevadensis) and the endangered Pahrump poolfish (Empetrichthys latos latos). Chapter one is a literature review on the impacts of invasive species on various desert fishes. Chapter Two reports the results of multiple mesocosm experiments that show poolfish are unlikely to persist in the presence of mosquitofish. Chapter Three reports the results of a mesocosm experiment that tested the combined impacts of crayfish and mosquitofish on poolfish populations. Chapter Three mimics a historic case study in Nevada, where the Lake Harriett poolfish population crashed following the introduction of crayfish and mosquitofish. Chapter Four reports results of a mesocosm experiment that revealed density dependent effects of invasive crayfish on pupfish populations, with pupfish populations negatively affected when crayfish were at high densities.Nevada State Wildlife GrantNorth Dakota State University. Environmental and Conservation Science ProgramDesert Fish Counci
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