4,383 research outputs found

    Machine learning with neuroimaging data to identify autism spectrum disorder: a systematic review and meta-analysis

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    Purpose: Autism Spectrum Disorder (ASD) is diagnosed through observation or interview assessments, which is time-consuming, subjective, and with questionable validity and reliability. Thus, we aimed to evaluate the role of machine learning (ML) with neuroimaging data to provide a reliable classification of ASD. Methods: A systematic search of PubMed, Scopus, and Embase was conducted to identify relevant publications. Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) was used to assess the studies’ quality. A bivariate random-effects model meta-analysis was employed to evaluate the pooled sensitivity, the pooled specificity, and the diagnostic performance through the hierarchical summary receiver operating characteristic (HSROC) curve of ML with neuroimaging data in classifying ASD. Meta-regression was also performed. Results: Forty-four studies (5697 ASD and 6013 typically developing individuals [TD] in total) were included in the quantitative analysis. The pooled sensitivity for differentiating ASD from TD individuals was 86.25 95% confidence interval [CI] (81.24, 90.08), while the pooled specificity was 83.31 95% CI (78.12, 87.48) with a combined area under the HSROC (AUC) of 0.889. Higgins I2 (> 90%) and Cochran’s Q (p < 0.0001) suggest a high degree of heterogeneity. In the bivariate model meta-regression, a higher pooled specificity was observed in studies not using a brain atlas (90.91 95% CI [80.67, 96.00], p = 0.032). In addition, a greater pooled sensitivity was seen in studies recruiting both males and females (89.04 95% CI [83.84, 92.72], p = 0.021), and combining imaging modalities (94.12 95% [85.43, 97.76], p = 0.036). Conclusion: ML with neuroimaging data is an exciting prospect in detecting individuals with ASD but further studies are required to improve its reliability for usage in clinical practice

    Expression of the Aeluropus littoralis AlSAP gene enhances rice yield under field drought at the reproductive stage

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    We evaluated the yields of Oryza sativa L. 'Nipponbare' rice lines expressing a gene encoding an A20/AN1 domain stress-associated protein, AlSAP, from the halophyte grass Aeluropus littoralis under the control of different promoters. Three independent field trials were conducted, with drought imposed at the reproductive stage. In all trials, the two transgenic lines, RN5 and RN6, consistently out-performed non-transgenic (NT) and wild-type (WT) controls, providing 50–90% increases in grain yield (GY). Enhancement of tillering and panicle fertility contributed to this improved GY under drought. In contrast with physiological records collected during previous greenhouse dry-down experiments, where drought was imposed at the early tillering stage, we did not observe significant differences in photosynthetic parameters, leaf water potential, or accumulation of antioxidants in flag leaves of AlSAP-lines subjected to drought at flowering. However, AlSAP expression alleviated leaf rolling and leaf drying induced by drought, resulting in increased accumulation of green biomass. Therefore, the observed enhanced performance of the AlSAP-lines subjected to drought at the reproductive stage can be tentatively ascribed to a primed status of the transgenic plants, resulting from a higher accumulation of biomass during vegetative growth, allowing reserve remobilization and maintenance of productive tillering and grain filling. Under irrigated conditions, the overall performance of AlSAP-lines was comparable with, or even significantly better than, the NT and WT controls. Thus, AlSAP expression inflicted no penalty on rice yields under optimal growth conditions. Our results support the use of AlSAP transgenics to reduce rice GY losses under drought conditions. (Résumé d'auteur

    ENV-639: IMPACT OF VEGETATION TYPE AND CLIMATE ON EVAPOTRANSPIRATION FROM EXTENSIVE GREEN ROOFS

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    Stormwater management solutions are needed to increase resiliency within urban areas by: (1) maintaining the natural hydrologic cycle, (2) controlling erosion and flooding, and (3) protecting water quality (MOE, 2003). Large impervious areas from urban development results in the loss of vegetated surfaces which leads to an increase in direct runoff (e.g. Paul and Meyer, 2008). Within urban areas, conventional roofs cover 40-50% of the impervious surfaces giving them significant potential to host urban stormwater management solutions (Dunnett and Kingsbury, 2004). Green roofs are able to restore the altered hydrologic cycle closer to its natural state by reducing the volume of runoff from a roof as well as attenuating flowrates. The hydrologic benefits of green roofs are partially attributed due to the vegetated surfaces enhancing evapotranspiration (ET) in urban areas. Predicting ET from green roofs is critical to inform green roof design and for optimization of hydrologic performance. This study focuses on evaluating the influence of green roof design parameters, such as vegetation type and growth media depth, on ET and by extension the hydrologic performance of an extensive green roof. While many studies have now demonstrated the effectiveness of green roofs in attenuating flowrate and reducing the volume of stormwater runoff (e.g., VanWoert et al., 2005a, Fassman-Beck et al., 2013, Berndtsson, 2010), little field research has been completed on directly quantifying ET rates and the hydrologic benefits green roofs in Canada including the influence of different vegetation types. The lack of available data on ET rates from green roofs limits optimal green roof design under the Canadian climate

    Are working memory and glutamate concentrations involved in early-life stress and severity of psychosis?

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    Objective Occurrences of early‐life stress (ELS) are associated with the severity of psychotic symptoms and working memory (WM) deficits in patients with psychosis (PSY). This study investigated potential mediation roles of WM behavioral performance and glutamate concentrations in prefrontal brain regions on the association between ELS and psychotic symptom severity in PSY. Method Forty‐seven patients with PSY (established schizophrenia, n = 30; bipolar disorder, n = 17) completed measures of psychotic symptom severity. In addition, data on ELS and WM performance were collected in both patients with PSY and healthy controls (HC; n = 41). Resting‐state glutamate concentrations in the bilateral dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC) were also assessed with proton magnetic resonance spectroscopy for both PSY and HC groups. t tests, analyses of variance, and regression analyses were utilized. Results Participants with PSY reported significantly more ELS occurrences and showed poorer WM performance than HC. Furthermore, individuals with PSY displayed lower glutamate concentrations in the left DLPFC than HC. Neither ELS nor WM performance were predictive of severity of psychotic symptoms in participants with PSY. However, we found a significant negative correlation between glutamate concentrations in the left DLPFC and ELS occurrence in HC only. Conclusion In individuals with PSY, the current study found no evidence that the association between ELS and psychotic symptoms is mediated by WM performance or prefrontal glutamate concentrations. In HC, the association between ELS experience and glutamate concentrations may indicate a neurometabolite effect of ELS that is independent of an illness effect in psychosis

    Mercury adsorption on natural and organofunctionalized smectites - thermodynamics of cation removal

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    A natural smectite clay sample from Piauí State, Brazil, was organofunctionalized with 3-mercaptopropyltrimethoxysilane and 3-aminopropyltriethoxysilane silyating agents. The basal spacing of 0.99 nm and surface area of 48 m² g-1 for natural clay increased to 1.84 and 2.01 nm, and 781 and 795 m² g-1 for modified clays, respectively. The natural and chemically immobilized clay samples adsorb mercury cations from aqueous solutions at pH 3.0 at 298 ± 1 K. The Langmuir, Redlich-Peterson and Toth adsorption isotherm models were applied to fit the experimental data with a nonlinear approach. From the cation/basic center interactions for each smectite at the solid-liquid interface, by using calorimetry methodology, the equilibrium constant and exothermic thermal effects were obtained. By considering the net interactive number of moles for each cation and the equilibrium constant, the enthalpy, intHº (-11.98 to -13.93 kJ mol-1) and negative free Gibbs energy, intGº (-22.4 ± 0.1 to -23.9 ± 0.1 kJ mol-1) were calculated. These values enabled the determination of positive entropy, intSº (51 ± 01 to 55 ± 2 J K-1 mol-1). The cation-basic center interactions are spontaneous in nature as demonstrated from favorable enthalpic and entropic results. Natural and anchored smectites have the ability to complex mercury, acting as useful materials for removal of this hazardous metal from an ecosystem.Uma amostra natural de esmectita oriunda do estado do Piauí, Brasil, foi organofuncionalizada com 3-mercaptopropiltrimethoxissilano e 3-aminopropiltriethoxissilano. O espaçamento basal da argila natural é de 0,99 nm e área superficial 48 m² g-1. Houve um aumento no espaçamento basal para 1,84 e 2,01 nm e o aumento da área específica para 781 e 795 m² g-1 para as argilas quimicamente modificadas, respectivamente. A argila natural e a argila quimicamente modificada adsorveram cátions mercúrio em solução aquosa em pH 3,0 e 298 ± 1 K. Os modelos de isotermas de adsorção de Langmuir, Redlich-Peterson e Toth foram aplicados para ajuste dos dados experimentais com aproximação não linear. Para as interações cátion/centros básicos para cada esmectita na interface sólido/líquido foi utilizada metodologia calorimétrica e foram obtidas as constantes de equilíbrio e os efeitos térmicos exotérmicos. Considerando o número interativo de moles para cada cátion e as constantes de equilíbrio, a entalpia, intHº (-11,98 a -13,93 kJ mol-1) e a energia livre de Gibbs negativa, intGº (-22,4 ± 0,1 a -23,9 ± 0,1 kJ mol-1) foram calculadas, o que permitiram a determinação da entropia positiva intSº (51 ± 01 a 55 ± 2 J K-1 mol-1). As interações cátion/centros básicos são de natureza espontânea como demonstram os valores de energia livre de Gibbs, dando o conjunto de dados favoráveis como expressam a entalpia exotérmica e a entropia positiva, mostrando que a esmectita natural e as quimicamente modificadas têm habilidade em complexar mercúrio. Logo, esses materiais são úteis na remoção de mercúrio em um ecossistema.594603Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Preliminary assessment of diffused loads from rural areas in a sub-basin of the Jaguari River, SP, Brazil

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    Official water quality and flow data from Jaguari River were used to assess the diffused loads of nutrients from rural areas into surface waters. Mathematical models of mean daily loads of total nitrogen (TN) and total phosphorus (TP) were generated through the application of simple statistical procedures to field data collected from 1999 to 2002. The models obtained were validated with field data collected from 1996 to 1998. The application of the model showed that, on average, 68.2% of the TN annual loads and 77.3% of the TP annual loads were transported through the sub-basin during the raining season. Assuming the mean baseflow loads as 1706.5 kg TN d-1 and 165.7 kg TP d-1, the annual diffused loads obtained - primarily from rural sources - were equivalent to 55.1 and 69.4% of the total annual loads of TN and TP transported through the sub - basin, respectively. The mean export coefficients from diffused loads for TN and TP were equal to 230 and 40 kg km-2 year-1, respectively. In may be concluded that controlling the diffused loads of TP from rural areas should decrease the high concentrations observed.Dados oficiais de concentração de nutrientes e vazão do Rio Jaguari, foram utilizados na avaliação das contribuições difusas, com origem rural, às águas superficiais de uma sub-bacia do Rio Jaguari, SP. Modelos de cargas médias diárias de Ntotal e Ptotal foram gerados a partir de regressão estatística aplicada a dados de campo obtidos entre 1999 e 2002. A validação dos modelos foi feita utilizando-se dados de campo obtidos entre 1996 e 1998. O modelo mostrou que, em média, 68,2% das cargas anuais de Ntotal e 77,3% das cargas anuais de Ptotal foram transportados pela sub-bacia no período chuvoso. Partindo-se de cargas de base diárias de 1706,5 kg Ntotal e de 165,7 kg Ptotal, determinou-se que 55,1 e 69,4% das cargas anuais totais de Ntotal e Ptotal, respectivamente, transportadas pela sub-bacia, provieram de fontes difusas. As taxas de exportação de nutrientes por carga difusa, obtidas pela aplicação do modelo, foram iguais a 230 kg Ntotal km-2 ano-1 e 40 kg Ptotal km-2 ano-1. Concluiu-se que o controle das fontes difusas de Ptotal, a partir de áreas rurais, deverá diminuir as concentrações deste nutriente no Rio Jaguari.715723Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

    Mercury adsorption on natural and organofunctionalized smectites - thermodynamics of cation removal

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    A natural smectite clay sample from Piauí State, Brazil, was organofunctionalized with 3-mercaptopropyltrimethoxysilane and 3-aminopropyltriethoxysilane silyating agents. The basal spacing of 0.99 nm and surface area of 48 m² g-1 for natural clay increased to 1.84 and 2.01 nm, and 781 and 795 m² g-1 for modified clays, respectively. The natural and chemically immobilized clay samples adsorb mercury cations from aqueous solutions at pH 3.0 at 298 ± 1 K. The Langmuir, Redlich-Peterson and Toth adsorption isotherm models were applied to fit the experimental data with a nonlinear approach. From the cation/basic center interactions for each smectite at the solid-liquid interface, by using calorimetry methodology, the equilibrium constant and exothermic thermal effects were obtained. By considering the net interactive number of moles for each cation and the equilibrium constant, the enthalpy, "intHº (-11.98 to -13.93 kJ mol-1) and negative free Gibbs energy, "intGº (-22.4 ± 0.1 to -23.9 ± 0.1 kJ mol-1) were calculated. These values enabled the determination of positive entropy, "intSº (51 ± 01 to 55 ± 2 J K-1 mol-1). The cation-basic center interactions are spontaneous in nature as demonstrated from favorable enthalpic and entropic results. Natural and anchored smectites have the ability to complex mercury, acting as useful materials for removal of this hazardous metal from an ecosystem
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