High electrical conductivity and high Seebeck coefficient are the two important prerequisites for achieving high power factor in organic thermoelectric (TE) materials. However, these two properties ...are quite often in conflict. In this work, we demonstrate that incorporating CNT in a conducting polymer PEDOT:PSS could facilitate the formation of stable and effective conductive channels, which provides an effective approach to optimize the TE parameters with simultaneously enhanced electrical conductivity and Seebeck coefficient against the initial organic TE materials. With further tailoring charge concentration of the SWNT/PEDOT:PSS composite by base treatment, the TE performance could be improved. Nanocomposite of 60 wt% SWNT and PEDOT:PSS exhibits high TE power factor of ∼526 μW m−1 K−2 with Seebeck coefficient of 55.6 μV K−1 and electrical conductivity of 1701 S cm−1, which is by far one of the highest power factors among the reported organic TE nanocomposites. Considering thermal conductivity around 0.4–0.6 W/m K, the highest estimated ZT value of our TE nanocomposite can approach 0.39, demonstrating the feasibility of this strategy to enhance TE performance of organic composite materials.
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Current image captioning methods are usually trained via maximum likelihood estimation. However, the log-likelihood score of a caption does not correlate well with human assessments of quality. ...Standard syntactic evaluation metrics, such as BLEU, METEOR and ROUGE, are also not well correlated. The newer SPICE and CIDEr metrics are better correlated, but have traditionally been hard to optimize for. In this paper, we show how to use a policy gradient (PG) method to directly optimize a linear combination of SPICE and CIDEr (a combination we call SPIDEr): the SPICE score ensures our captions are semantically faithful to the image, while CIDEr score ensures our captions are syntactically fluent. The PG method we propose improves on the prior MIXER approach, by using Monte Carlo rollouts instead of mixing MLE training with PG. We show empirically that our algorithm leads to easier optimization and improved results compared to MIXER. Finally, we show that using our PG method we can optimize any of the metrics, including the proposed SPIDEr metric which results in image captions that are strongly preferred by human raters compared to captions generated by the same model but trained to optimize MLE or the COCO metrics.
The accurate diagnosis of Alzheimer's disease (AD) is essential for patient care and will be increasingly important as disease modifying agents become available, early in the course of the disease. ...Although studies have applied machine learning methods for the computer-aided diagnosis of AD, a bottleneck in the diagnostic performance was shown in previous methods, due to the lacking of efficient strategies for representing neuroimaging biomarkers. In this study, we designed a novel diagnostic framework with deep learning architecture to aid the diagnosis of AD. This framework uses a zero-masking strategy for data fusion to extract complementary information from multiple data modalities. Compared to the previous state-of-the-art workflows, our method is capable of fusing multimodal neuroimaging features in one setting and has the potential to require less labeled data. A performance gain was achieved in both binary classification and multiclass classification of AD. The advantages and limitations of the proposed framework are discussed.
The depletion of the Earth's fossil fuel reserves and the rapid increase in the emission of greenhouse gases and other environmental pollutants are driving the development of renewable energy ...technologies. Lignin is one of the three main subcomponents of lignocellulosic biomass in terrestrial ecosystems and makes up nearly 30% of the organic carbon sequestered in the biosphere. As a result of its rich content of aromatic carbon, lignin has the potential to be decomposed to yield valuable chemicals and alternatives to fossil fuels. However, the complex and stable chemical bonds of lignin make the depolymerization of lignin a difficult challenge with regard to its valorization. In this review, we highlight recent advances in the selective decomposition of lignin-based compounds
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photocatalysis into other value-added chemicals and the treatment of waste water containing lignin. The photocatalytic transformation of lignin under mild conditions is particularly promising.
Photocatalysis as an approach for lignin valorization from energy and environmental viewpoints.
The severe consequences of fossil fuel consumption have resulted in a need for alternative sustainable sources of energy. Conversion and storage of solar energy
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a renewable method, such as ...photocatalysis, holds great promise as such an alternative. One-dimensional (1D) nanostructures have gained attention in solar energy conversion because they have a long axis to absorb incident sunlight yet a short radial distance for separation of photogenerated charge carriers. In particular, well-ordered spatially high dimensional architectures based on 1D nanostructures with well-defined facets or anisotropic shapes offer an exciting opportunity for bridging the gap between 1D nanostructures and the micro and macro world, providing a platform for integration of nanostructures on a larger and more manageable scale into high-performance solar energy conversion applications. In this review, we focus on the progress of photocatalytic solar energy conversion over controlled one-dimension-based spatially ordered architecture hybrids. Assembly and classification of these novel architectures are summarized, and we discuss the opportunity and future direction of integration of 1D materials into high-dimensional, spatially organized architectures, with a perspective toward improved collective performance in various artificial photoredox applications.
The current status, future developments, and challenges of one-dimension-based spatially ordered architectures in solar energy conversion are discussed and elucidated.
The core of urbanization is land use change, resulting in the urban sprawl and urban population explosion. The problem of land resources shortage and ecological environment destruction has become ...increasingly prominent. Land use change and human activities can directly lead to urban soil pollution. This study analyzed the concentration of Cd, Cr, Cu, Ni, Pb, Zn, Hg and As in the original site of Xi'an chlor-alkali chemical plant, which was know as a brownfield. The results showed the concentrations of Hg, Pb and Zn in research areas were obviously higher than soil background value. Through pollution index (PI) method and Geo-accumulation Index (Igeo) method, totally 26 sample points in different areas (A, B, C, D) were classified into different pollution degrees. The CPI results indicated 9 sample points were heavily polluted, accounting for 34.6% of the total. Among them, 6 out of 9 were located in area A. 12 samples points were not polluted. The average Igeo values of single heavy metal were arranged in the order of Hg (1.83) > Zn (1.26) > Pb (0.33). The pollution of Hg was relatively serious and extensive, especially in area A. It was mainly because of the historical pollution produced by chemical plant. The pollution of Pb in each point was quite different. Mainly influenced by automobile related activities, Igeo(Pb) in sample point 15 and 16 were all beyond 4.00. The average potential ecological risk (PER) of each area was in the order of A (1428) > B (297) > D (249) > C (163). The ecological risk was mainly determined by previous industrial production and present human activity at the same time. People and land are interdependent and interactive. The understanding on the mechanism of man-land interralations, regarding to urban land use and ecological environment, will promote urban sustainability.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
During virus infection, the adaptor proteins MAVS and STING transduce signals from the cytosolic nucleic acid sensors RIG-I and cGAS, respectively, to induce type I interferons (IFNs) and other ...antiviral molecules. Here we show that MAVS and STING harbor two conserved serine and threonine clusters that are phosphorylated by the kinases IKK and/or TBK1 in response to stimulation. Phosphorylated MAVS and STING then bind to a positively charged surface of interferon regulatory factor 3 (IRF3) and thereby recruit IRF3 for its phosphorylation and activation by TBK1. We further show that TRIF, an adaptor protein in Toll-like receptor signaling, activates IRF3 through a similar phosphorylation-dependent mechanism. These results reveal that phosphorylation of innate adaptor proteins is an essential and conserved mechanism that selectively recruits IRF3 to activate the type I IFN pathway.
Photocatalysis is a promising and convenient strategy to convert solar energy into chemical energy for various fields. However, photocatalysis still suffers from low solar energy conversion ...efficiency. Developing state of the art photocatalysts with high efficiency and low cost is a huge challenge. Transition metal nitrides (TMNs) as a class of metallic interstitial compounds have attracted significant attention in photocatalytic applications. In fact, TMNs exhibit multifunctional properties in various photocatalytic systems. This review is the first attempt that summarizes recent research on TMNs‐based materials in various photocatalytic applications. Different roles of TMNs materials in photocatalytic systems including semiconductor active components, co‐catalysts, inter‐band excitation, and surface plasmon resonance components are systematically discussed and summarized. The fundamentals, latest progress, and emerging opportunities for further improving the performances of TMNs‐based materials for photocatalysis are also discussed. Finally, some challenges facing TMNs, and perspectives on their future that are relevant for furthering research in the area of photocatalysis are also proposed.
This review summarizes recent research on TMNs‐based materials in various photocatalytic applications including water splitting, CO2 reduction, and dye degradation. Different roles of TMNs materials in photocatalytic systems such as semiconductor active components, co‐catalysts, inter‐band excitation, and surface plasmon resonance components are systematically discussed and summarized.
Pathogens and cellular danger signals activate sensors such as RIG-I and NLRP3 to produce robust immune and inflammatory responses through respective adaptor proteins MAVS and ASC, which harbor ...essential N-terminal CARD and PYRIN domains, respectively. Here, we show that CARD and PYRIN function as bona fide prions in yeast and that their prion forms are inducible by their respective upstream activators. Likewise, a yeast prion domain can functionally replace CARD and PYRIN in mammalian cell signaling. Mutations in MAVS and ASC that disrupt their prion activities in yeast also abrogate their ability to signal in mammalian cells. Furthermore, fibers of recombinant PYRIN can convert ASC into functional polymers capable of activating caspase-1. Remarkably, a conserved fungal NOD-like receptor and prion pair can functionally reconstitute signaling of NLRP3 and ASC PYRINs in mammalian cells. These results indicate that prion-like polymerization is a conserved signal transduction mechanism in innate immunity and inflammation.
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•MAVS and ASC exhibit hallmarks of prions in yeast and mammalian cells•The prion forms of MAVS and ASC activate downstream signaling•Mutations that impair MAVS and ASC prion formation abolish their functions•Signaling through prion-like polymerization is conserved from fungi to mammals
The adaptor proteins MAVS and ASC form self-perpetuating prion-like polymers to propagate innate immune and inflammatory signaling. Prion-like switch is a conserved mechanism of signal transduction from fungi to mammals.
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