The rapid development of portable/wearable electronics proposes new demands for energy storage devices, which are flexibility, smart functions and long-time outdoor operation. Supercapacitors (SCs) ...show great potential in portable/wearable applications, and the recently developed flexible, smart and self-sustainable supercapacitors greatly meet the above demands. In these supercapacitors, conductive polymers (CPs) are widely applied due to their high flexibility, conductivity, pseudo-capacitance, smart characteristics and moderate preparation conditions. Herein, we'd like to introduce the CP-based flexible, smart and self-sustainable supercapacitors for portable/wearable electronics. This review first summarizes the flexible SCs based on CPs and their composites with carbon materials and metal compounds. The smart supercapacitors,
i.e.
, electrochromic, electrochemical actuated, stretchable, self-healing and stimuli-sensitive ones, are then presented. The self-sustainable SCs which integrate SC units with energy-harvesting units in one compact configuration are also introduced. The last section highlights some current challenges and future perspectives of this thriving field.
Progress of utilizing conductive polymers and their composites to prepare flexible, smart and self-sustainable supercapacitors for portable/wearable electronics is reviewed.
Increasing utilization of stabilized iron sulfides (FeS) nanoparticles implies an elevated release of the materials into the environment. To understand potential impacts and underlying mechanisms of ...nanoparticle-induced stress, we used the transcriptome sequencing (RNA-seq) technique to characterize the transcriptomes from adult zebrafish exposed to 10 mg/L carboxymethyl cellulose (CMC) stabilized FeS nanoparticles for 96 h, demonstrating striking differences in the gene expression profiles in liver. The exposure caused significant expression alterations in genes related to immune and inflammatory responses, detoxification, oxidative stress and DNA damage/repair. The complement and coagulation cascades Kyoto encyclopedia of genes and genomes (KEGG) pathway was found significantly up-regulated under nanoparticle exposure. The quantitative real-time polymerase chain reaction using twelve genes confirmed the RNA-seq results. We identified several candidate genes commonly regulated in liver, which may serve as gene indicators when exposed to the nanoparticles. Hepatic inflammation was further confirmed by histological observation of pyknotic nuclei, and vacuole formation upon exposure. Tissue accumulation tests showed a 2.2 times higher iron concentration in the fish tissue upon exposure. This study provides preliminary mechanistic insights into potential toxic effects of organic matter stabilized FeS nanoparticles, which will improve our understanding of the genotoxicity caused by stabilized nanoparticles.
The freezing–thawing deformation is a key factor in determining damages for engineering structures in cold regions. Based on the laboratory experiments, the characteristics of the freezing–thawing ...deformation were analyzed, as well as the variation of the matric suction. The results show that in each freeze–thaw cycle, the freezing–thawing deformation can be divided into five stages, i.e. cold shrink, fast frost heave, slow frost heave, thermal bulge and thaw settlement. At the onset of each cooling process, the cold shrink occurs and the freezing–thawing deformation decreases slightly; and then, with the decreased temperature, the freezing–thawing deformation rapidly increases at the beginning of freezing (fast frost heave); and subsequently slowly increases with freezing. During the warming processes, the bulge occurs with the rapid increase of the ambient temperature; later, with the thawing of ice, the freezing–thawing deformation decreases. Besides, there are similar changing trends for the freezing–thawing deformation and the matrix suction during the freezing–thawing processes. However, their changing mechanisms are completely different, and the soil matric suction has a stronger sensitivity to the variation of the volumetric unfrozen water content. Furthermore, the effect of freeze–thaw cycles on the characteristic variables of the freezing–thawing deformation, such as cold shrink, net deformation, frost heave coefficient and thaw-settlement coefficient, mainly occurs in the first freeze–thaw cycle, which may be due to the fact that the first freeze–thaw cycle has a significant influence on the soil structure and pore distribution for the remolded sample.
•The freezing-thawing deformation of a silty clay was experimentally studied.•Although there are similar changing trends for the deformation and the matrix suction during the freezing-thawing processes, their changing mechanisms are completely different.•The first freeze–thaw cycle has the most significant effect on the characteristic variables of the freezing–thawing deformation for the remolded soil.
Drug repurposing is the process of discovering new indications (i.e., diseases or conditions) for already approved drugs. Many computational methods have been proposed for predicting new associations ...between drugs and diseases. In this article, we proposed a new method, called DR-HGNN, an integrative heterogeneous graph neural network-based method for multi-labeled drug repurposing, to discover new indications for existing drugs. For this purpose, we first used the DTINet dataset to construct a heterogeneous drug–protein–disease (DPD) network, which is a graph composed of four types of nodes (drugs, proteins, diseases, and drug side effects) and eight types of edges. Second, we labeled each drug–protein edge,
dp
i
,
j
= (
d
i
,
p
j
), of the DPD network with a set of diseases, {
δ
i
,
j
,1
, … ,
δ
i
,
j
,
k
} associated with both
d
i
and
p
j
and then devised multi-label ranking approaches which incorporate neural network architecture that operates on the heterogeneous graph-structured data and which leverages both the interaction patterns and the features of drug and protein nodes. We used a derivative of the GraphSAGE algorithm, HinSAGE, on the heterogeneous DPD network to learn low-dimensional vector representation of features of drugs and proteins. Finally, we used the drug–protein network to learn the embeddings of the drug–protein edges and then predict the disease labels that act as bridges between drugs and proteins. The proposed method shows better results than existing methods applied to the DTINet dataset, with an AUC of 0.964.
•Various factors influence the heat flux and soil temperature of soil-rock mixtures.•Damping properties of heat flow for soil-rock mixtures were found and illustrated.•A new generalized thermal ...resistance model for soil-rock mixtures was proposed.
As a special heterogeneous geological material, soil-rock mixtures are widely distributed in nature and used in civil engineering. Heat flow is one of the most significant factors affecting the development of water balance and redistribution, ground temperature evolution, and heat transport processes in cold regions. This study explores the heat flow characteristics and generalized thermal resistance model for soil-rock mixtures during freezing-thawing processes. A series of freezing-thawing experiments for soil-rock mixtures with different rock contents (i.e., 10%, 25%, and 40%) were conducted. The effects of rock content and water–ice phase transition on heat flux during the freezing-thawing processes were analyzed, and the damping properties of heat flow for soil-rock mixtures during freeze–thaw cycles were found and illustrated. Subsequently, a generalized thermal resistance model for soil-rock mixtures was proposed and discussed. The results show that the freezing-thawing processes and rock content significantly influence the heat flux and soil temperature of the soil-rock mixtures. Regardless of rock content, the sums of heat flux in freezing and thawing stages all firstly decreased, and then gradually tends to be stable with freeze–thaw cycles. Besides, the reduction of volumetric unfrozen water content increases with the freeze–thaw cycles, and the amplitude of unfrozen water reduction for sample with high rock content is larger than that with low rock content. Additionally, owing to the effect of the latent heat released by water/ice phase transition and thermal sensitive property of rock, the variation of heat flow for soil-rock mixtures presents damping property in the stages without completely freezing, and the variation of heat flow exhibits reversed damping property in the post-freezing stages due to the denser structure and ice crystal growth. Furthermore, based on the thermal resistance in series, characteristics of water–ice phase transition, and thermal sensitive property of rocks, a new generalized thermal resistance model of soil-rock mixtures during freezing-thawing processes is proposed.
This paper discusses the bias problem when estimating the population size of big data such as online social networks (OSN) using uniform random sampling and simple random walk. Unlike the traditional ...estimation problem where the sample size is not very small relative to the data size, in big data, a small sample relative to the data size is already very large and costly to obtain. We point out that when small samples are used, there is a bias that is no longer negligible. This paper shows analytically that the relative bias can be approximated by the reciprocal of the number of collisions; thereby, a bias correction estimator is introduced. The result is further supported by both simulation studies and the real Twitter network that contains 41.7 million nodes.
•The theory of premelting in the presence of impurities in soils is developed.•A model to predict the variation of unfrozen water content is established.•Equivalent grain size is introduced to soils ...to calculate unfrozen water content.•The thickness of water film is mainly determined by the impurity concentration.
The variation of unfrozen water content with temperature has a significant effect on the coupled heat-water transport in freezing soil, which can cause the frost heave and thaw settlement, and thus influence the stability of infrastructures. The premelting theory for water–ice in soils is developed to study the unfrozen water variation in freezing soil. The developed theory integrates the interfacial premelting of contact ice, the soil particles, the melting of the ice surface, and the premelting induced by impurity and curvature. A model to predict the unfrozen water content is then established by considering the change of unfrozen water film. The equivalent grain size is introduced to improve the solving efficiency in the calculation. Finally, the proposed analytical model is verified by the test data. The results indicate that the thickness of water film in soils increases when the surface charge density and the impurity concentration increase under the same supercooling degree. The surface melting on the interfaces of soil particle and the pore ice has key influence on the variation of the liquid water content. Meanwhile, the unfrozen water content increases with the increasing impurity concentration and surface charge on soil particles. Besides, the unfrozen water content also increases with the decreasing radius of soil particles.
It is commonly considered that the morphology and interface of semiconductor–reduced graphene oxide (rGO) composite photocatalysts play a crucial role in determining their photocatalyzing ...performance. Herein, we report on the design and synthesis of BiVO4–rGO nanocomposites with efficient interfacial contact by self-assembly of positively charged amorphous BiVO4 powders with negatively charged graphene oxide (GO), followed by a one-step GO reduction and BiVO4 crystallization via hydrothermal treatment. The as-prepared BiVO4–rGO nanocomposites exhibit high visible light photocatalytic efficiency for the degradation of model dyes, and are significantly superior to bare crystalline BiVO4 and BiVO4–rGO–U that is hydrothermally synthesized using the mixture of GO nanosheets and BiVO4 powders without modification of surface charge. Using multiple characterization techniques, we found that the enhanced photocatalytic performance of BiVO4–rGO arises from the synergistic effects between the microscopic crystal structure of BiVO4 with smaller particle size and more sufficient interfacial interaction between BiVO4 and graphene sheets, leading to increased photocatalytic reaction sites, extended photoresponding range, enhanced photogenerated charge separation, and transportation efficiency. This work may provide a rational and convenient strategy to construct highly efficient semiconductor–rGO nanocomposite photocatalysts with well-contacted interface toward environmental purification and solar energy conversion.
In this study, the variations of the temperatures and volumetric unfrozen water contents for two fine-grained soils (i.e., silty clay and silt) with high degrees of saturation during a ...freezing–thawing process were experimentally studied. Experimental results show that for the two soils, the supercooling phenomenon only happens in the early stage of freezing process, and the supercooling temperature and its duration of the silty clay are both larger than those of the silt under similar temperatures; furthermore, the hysteresis effect of volumetric unfrozen water content exists during the whole freezing–thawing process, and the maximum hysteresis levels both occur at the soil freezing points; however, the maximum value of the hysteresis level of the silt is larger than that of the silty clay.
The yellow catfish, Pelteobagrus fulvidraco, is a commercially important fish species. It is widely distributed in the fresh water areas of China, including rivers, lakes, and reservoirs. Like many ...other aquaculture fish species, people have observed significant size dimorphism between male and female yellow catfish and it shows a growth advantage in males.
Here, at the first time, the time-course transcriptome was used to explore the various expression profiles of genes in different gonad developmental stages and genders. A total of 2696 different expression genes (DEGs) were identified from different stages. Based on these DEGs, 13 gonad development related genes were identified which showed time-specific or sex biased expression patterns.
This study will provide the crucial information on the molecular mechanism of gonad development of female and male yellow catfish. Especially, during the different gonad development stages, these 13 gonad development related genes exhibit various expression patterns in female and male individual respectively. These results could inspire and facilitate us to understanding the various roles of these genes play in different gonad development stages and genders.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
