50 research outputs found

    Relações entre características do autismo, variáveis emocionais e o processamento olfativo na população geral

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    Although altered sensory processing is recognized as a key-feature of Autism Spectrum Disorder (henceforth “autism”), olfactory functioning is still poorly understood in this condition. Considering the role of olfaction in human social communication and well-being, it is crucial to investigate which variables are related to the often-observed inconsistent results concerning olfactory functioning in autism. Study of the expression of autism traits and other autism-related variables in the general population may be useful to understand which specific dimensions are related to the often-observed symptoms, alterations, and heterogeneity in the autism spectrum, including in the olfactory domain. The present work sought to contribute to the multidimensional assessment of anxiety and autism traits in adults of the general population, as well as to the understanding of the multivariate relationships between autism characteristics, olfactory processing, anxiety, and alexithymia. Study 1 and Study 2 aimed to extend the available evidence about the psychometric properties of the State-Trait Inventory for Cognitive and Somatic Anxiety (STICSA) and the Autism Spectrum Quotient (AQ). Results supported the adequacy of both instruments to measure anxiety and autism traits, respectively, in a multidimensional perspective. Consistent with the literature, Study 1 found support for a four-factor, as well as a two-factor structure within the state and traits forms of the STICSA. Moreover, measurement invariance across sex groups, and good nomological validity were also supported for the STICSA. Results also suggested that the cognitive and somatic dimensions of trait anxiety, as measured by the STICSA, are differently related with the subjective and psychophysiological responses in distinct emotional contexts. Results of Study 2 further supported a three-factor structure of the AQ, consistent with previous studies, as well as the role of alexithymia, particularly difficulties in identifying feelings, as a mediator of the relationship between autism traits and trait anxiety. Study 3 analyzed the impact of the social skills and attention to detail dimensions of autism traits, and cognitive/somatic trait anxiety, on the olfactory abilities of the general population. Results emphasized the roles of sex, attention to detail and trait-somatic anxiety as significant predictors of odor discrimination abilities. Finally, Study 4 provided an integrative review about olfactory processing in autism and how advancing research in this area may benefit the knowledge and practice regarding social cognition and behavior in autism. The findings of this research highlight the need to explore the distinct dimensions of autism-related variables to better understand their complex relationships and impact in the functioning of the spectrum, including in olfactory functioning.Embora alterações no processamento sensorial sejam uma característica-chave da Perturbação do Espetro do Autismo (daqui em diante “autismo”), o funcionamento olfativo ainda é pouco compreendido nesta condição. Considerando o papel do olfato na comunicação, interação social e bem-estar, é crucial investigar que variáveis estão relacionadas com os resultados inconsistentes frequentemente observados no âmbito do processamento olfativo no autismo. Estudar a expressão de traços de autismo na população geral, bem como a expressão multidimensional de outras variáveis relacionadas, pode ser útil para compreender que dimensões estão relacionadas com os sintomas, alterações e heterogeneidade frequentemente observados no autismo, incluindo no domínio olfativo. O presente trabalho pretendeu contribuir para a avaliação multidimensional da ansiedade e de traços de autismo em adultos da população geral, bem como para uma melhor compreensão da relação multivariada entre as características do autismo, processamento olfativo, ansiedade e alexitimia. O Estudo 1 e o Estudo 2 tiveram como objetivo estender a evidência disponível sobre as propriedades psicométricas do State-Trait Inventory for Cognitive and Somatic Anxiety (STICSA) e do Autism Spectrum Quotient (AQ). Os resultados suportaram a adequação de ambos os instrumentos para medir ansiedade e traços de autismo, respetivamente, numa perspetiva multidimensional. Em linha com a literatura, o Estudo 1 providenciou suporte para uma estrutura de quatro fatores, bem como para uma estrutura de dois fatores dentro das dimensões de ansiedade traço e estado do STICSA. Observou-se ainda invariância fatorial considerando a variável sexo, assim como boa validade nomológica. Os resultados também sugeriram que as dimensões cognitivas e somáticas da ansiedade traço, medidas pelo STICSA, estão relacionadas de forma distinta com as respostas subjetiva e psicofisiológica em diferentes contextos emocionais. Os resultados do Estudo 2, de modo consistente com estudos anteriores, suportaram uma estrutura de três fatores do AQ, bem como o papel da alexitimia, particularmente das dificuldades em identificar sentimentos e emoções, como mediadora da relação entre traços de autismo e ansiedade traço. O Estudo 3 analisou o impacto das dimensões de traços de autismo relacionadas com as capacidades sociais e atenção para os detalhes, e da ansiedade traço cognitiva/somática, nas capacidades olfativas da população geral. Os resultados evidenciaram o papel das variáveis sexo, atenção para os detalhes e ansiedade traço somática como preditores significativos da capacidade de discriminação olfativa. Por fim, o Estudo 4 apresentou uma revisão integrativa sobre o processamento olfativo no autismo, e como o avanço da investigação nesta área pode beneficiar o conhecimento e a prática no âmbito da cognição e comportamento social. Os resultados desta investigação destacam a importância de explorar as diferentes dimensões das variáveis relacionadas com o autismo para melhor compreender a complexidade das suas relações e impacto no funcionamento do espetro, incluindo no que diz respeito ao funcionamento olfativo.Programa Doutoral em Psicologi

    Applicability domains of neural networks for toxicity prediction

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    In this paper, the term "applicability domain" refers to the range of chemical compounds for which the statistical quantitative structure-activity relationship (QSAR) model can accurately predict their toxicity. This is a crucial concept in the development and practical use of these models. First, a multidisciplinary review is provided regarding the theory and practice of applicability domains in the context of toxicity problems using the classical QSAR model. Then, the advantages and improved performance of neural networks (NNs), which are the most promising machine learning algorithms, are reviewed. Within the domain of medicinal chemistry, nine different methods using NNs for toxicity prediction were compared utilizing 29 alternative artificial intelligence (AI) techniques. Similarly, seven NN-based toxicity prediction methodologies were compared to six other AI techniques within the realm of food safety, 11 NN-based methodologies were compared to 16 different AI approaches in the environmental sciences category and four specific NN-based toxicity prediction methodologies were compared to nine alternative AI techniques in the field of industrial hygiene. Within the reviewed approaches, given known toxic compound descriptors and behaviors, we observed a difficulty in being able to extrapolate and predict the effects with untested chemical compounds. Different methods can be used for unsupervised clustering, such as distance-based approaches and consensus-based decision methods. Additionally, the importance of model validation has been highlighted within a regulatory context according to the Organization for Economic Co-operation and Development (OECD) principles, to predict the toxicity of potential new drugs in medicinal chemistry, to determine the limits of detection for harmful substances in food to predict the toxicity limits of chemicals in the environment, and to predict the exposure limits to harmful substances in the workplace. Despite its importance, a thorough application of toxicity models is still restricted in the field of medicinal chemistry and is virtually overlooked in other scientific domains. Consequently, only a small proportion of the toxicity studies conducted in medicinal chemistry consider the applicability domain in their mathematical models, thereby limiting their predictive power to untested drugs. Conversely, the applicability of these models is crucial; however, this has not been sufficiently assessed in toxicity prediction or in other related areas such as food science, environmental science, and industrial hygiene. Thus, this review sheds light on the prevalent use of Neural Networks in toxicity prediction, thereby serving as a valuable resource for researchers and practitioners across these multifaceted domains that could be extended to other fields in future research

    Liquefaction assessment methodologies for reclaimed land : a case study of the port of Wellington, New Zealand (CentrePort).

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    This study investigates the applicability of simplified semi-empirical and advanced dynamic liquefaction assessment methods to reclaimed soils using a comprehensive set of data for two types of reclamations at the port of Wellington, New Zealand (CentrePort) that are challenging for liquefaction assessment: end-dumped gravelly fills and hydraulically placed silty-sandy fills. The gravelly fills are the primary focus of this study as they are comprised of complex gravel-sand-silt (G-S-S) mixtures that are not well-represented in current liquefaction databases used to develop existing semi-empirical methods for liquefaction assessment. As such, existing procedures to evaluate triggering and consequences of liquefaction may not be directly applicable or may need additional considerations when applied to the gravelly mixtures encountered at CentrePort. The hydraulic fills are also of significant interest as they relate to a range of issues in the simplified engineering assessment around effects of fines and their plasticity on the liquefaction resistance. The detailed site characterization in the first part of this study, primarily based on CPT data and supplemented by borehole logs and index testing of borehole soil samples, show that the 10–22 m thick fill in the southern end of the port (i.e., the Thorndon reclamation) is composed of 60–80% fine- to-medium gravels and 20–40% finer sand-silt fractions. The proportion of sand and non-plastic silt in the G-S-S mixtures is sufficiently large for these finer fractions to govern the deformational behaviour and mechanical response of the matrix, as also suggested by the CPT characteristics (qc = 6–8 MPa; Ic = 1.9–2.3). The G-S-S fills in other parts of the port have similar CPT characteristics, however, the G-S-S layers are much thinner and contain several interbedded layers of non-liquefiable soils or soils with higher density. The hydraulic fill varies in thickness from 5 m to 10 m and is characterized by three distinct soil units. The sand-silt hydraulic fill (sands with 5–35% fines; qc ≈ 4.5 MPa; Ic ≈ 2.1) are most commonly encountered in the Log Yard, the silt-clay hydraulic fill (sands with 70–100% fines with mostly PI > 20; qc 3.0) is commonly encountered along Aotea Quay, and G- S-S mixtures (FC = 5–25%; GC = 15–55%; qc ≈ 5 MPa; Ic ≈ 2.0) are encountered in one location at Aotea Quay. An existing CPT-based simplified liquefaction evaluation method is applied to the CentrePort profiles and compared against liquefaction performance observed in three recent earthquakes. There is generally good agreement in the triggering assessment for seismic demands well above or below the liquefaction triggering threshold for the fills, but overestimation for seismic demands close to the triggering threshold. While the triggering methods themselves are unable to clearly discern between different performances, key differences in the thicknesses and locations of liquefied fills are better indicators of the liquefaction-induced damage and potential for manifestation at the ground surface. Simplified estimates of settlements perform well for the cases where liquefaction triggering results are generally in agreement with observed damage, though with slight underestimation. Calculation of damage indices also matched reasonably well with the general trends in the severity of damage observed for all three earthquakes across most of CentrePort. However, the damage indices provide lesser degree of variation in the ground performance as compared to actual observations. Two key issues in the simplified assessment of reclaimed fills are scrutinized. Firstly, uncertainty in the interpretation of material characterization on the triggering assessment are investigated through a sensitivity study. In particular, sensitivity of the computed response to uncertainties associated with effects of fines or complex soil composition on the liquefaction resistance (via FC or Ic parameters in the Boulanger and Idriss (2014) and Robertson and Wride (1998b) methods, respectively) are scrutinized in detail. These two triggering methods can result in over 50% difference in estimates of liquefaction resistance in the CentrePort fills (characterized by Ic = 2.0–2.3) due to modelling uncertainty in the material characterization. Results show that well- defined critical layers have low penetration resistance, and that sensitivity of liquefaction resistance to material parameters is the smallest for such layers, hence the uncertainty in the cyclic demand tends to dominate. However, the triggering methods are much more sensitive to the material characterization in soil layers with much larger penetration resistance. The second issue investigated is the grain-size effects on penetration resistance and associated estimates of settlements via relative density relationships. Sand-based procedures for evaluation of liquefaction-induced settlement are found to be generally applicable to well-graded gravels that have a dominant silty sand fraction in the soil matrix, though they can significantly overestimate the relative density and consequently underestimate post- liquefaction settlement of gravelly soils in the case of dense fills. Results from investigation of both issues above imply that the overall sensitivity in the simplified assessment is density dependent. Finally, a series of preliminary advanced dynamic effective stress analyses are performed for 13 representative profiles at CentrePort. Liquefaction resistance of advanced constitutive models are calibrated using CPT-based empirical relationships from simplified procedures, and hence the advanced numerical simulations of this study are consistent with the simplified liquefaction assessment in this regard. This facilitates comparative evaluation of the two approaches, and differences in performances reflect differences in modelling and analysis methodologies rather than in the liquefaction resistance characteristics. Overall, the dynamic effective stress analyses provide greater insight on the mechanisms of liquefaction, explains important dynamic interactions within the deposit, and explores the evolution of the system response for different seismic intensities. The analyses also explain some of the discrepancies between the observed performance and simplified methods. Comparison of damage indices calculated for the simplified methods with damage proxies from the dynamic simulations show reasonable agreement in the relative liquefaction performance for most sites across CentrePort, with some discrepancies identified

    Biological and Pharmacological Activity of Plant Natural Compounds II

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    The Special issue "Biological and Pharmacological Activity of Plant Natural Compounds II" is continuing the intriguing research on the use of natural plant products. The second edition follows the aim of the first one

    Marine Aquaculture in Maine: Understanding Diverse Perspectives and Interactions at Multiple Scales

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    Coastal oceans are changing and experiencing increased use. The social and ecological benefits of healthy coastal oceans are well documented and include habitats for marine species, storm protection, and recreational opportunities (MEA, 2005). As the impacts of human activities are recognized, questions about how ocean spaces should be used are becoming more common. These questions are complex and involve many tradeoffs. Understanding the values people hold about uses, and how activities and ecosystems overlap, is critical for weighing tradeoffs and improving future management. I use the northeastern U.S. state of Maine to study human interactions with coastal oceans. Maine is biologically productive and hosts commercial fishing, aquaculture, tourism, and renewable energy industries. I explore perspectives about aquaculture development at a statewide scale (Chapter 1), and intersections among scientific literature, human activities, and ecosystems in two estuaries in midcoast Maine (Chapter 2). Understanding these small-scale interactions is important for improving local management and can also provide information for larger-scale conversations. In Chapter 1, I focus on Maine’s aquaculture industry. I use the Q method to describe perspectives about aquaculture held by people who are familiar with the industry, and areas of consensus and disagreement among them. I identified four perspectives: the Aquaculture Optimists, the Aquaculture Anchors, the Aquaculture Historian, and the Aquaculture Agnostics. These groups valued Maine’s marine economy and felt aquaculture could play a role, but disagreed about the scope of the industry and the distribution of benefits. They also had different perspectives about the role of local communities in siting aquaculture farms. Understanding perspectives can contribute to dialogue about the future of the aquaculture industry in Maine and globally. In Chapter 2, I review literature about the Damariscotta River Estuary (DRE) in midcoast Maine. The DRE hosts three research institutions and is heavily studied on diverse marine science-related topics. This literature review supports a participatory mapping project using local ecological knowledge to map the spatial overlaps of shellfish and human use activities in the DRE, as well as observed changes and their causes. Preliminary results from the mapping study are in Appendix E. In the literature review, I describe the publications, their themes, locations, and the years in which they were published. I discuss missing themes and compare our literature review themes to a preliminary analysis of the participatory mapping project interview data. This identifies knowledge gaps about the estuary and highlights areas for future research. The large amount of data provides a valuable baseline for documenting change over time and shows the value of examining literature at an estuary-wide scale

    Exploring Co-creative Drawing Workflows

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    This article presents the outcomes from a mixed-methods study of drawing practitioners (e.g., professional illustrators, fine artists, and art students) that was conducted in Autumn 2018 as a preliminary investigation for the development of a physical human-AI co-creative drawing system. The aim of the study was to discover possible roles that technology could play in observing, modeling, and possibly assisting an artist with their drawing. The study had three components: a paper survey of artists' drawing practises, technology usage and attitudes, video recorded drawing exercises and a follow-up semi-structured interview which included a co-design discussion on how AI might contribute to their drawing workflow. Key themes identified from the interviews were (1) drawing with physical mediums is a traditional and primary way of creation; (2) artists' views on AI varied, where co-creative AI is preferable to didactic AI; and (3) artists have a critical and skeptical view on the automation of creative work with AI. Participants' input provided the basis for the design and technical specifications of a co-creative drawing prototype, for which details are presented in this article. In addition, lessons learned from conducting the user study are presented with a reflection on future studies with drawing practitioners
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