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The research on the anti-CO poisoning performance of Pt catalyst for direct methanol fuel cell (DMFC) has been the focus of scientists. Nafion membrane is one of the indispensable components in DMFC. In this paper, the effect of Nafion on the anti-CO poisoning of Pt catalyst was studied by density functional theory (DFT). It is found that under the action of Nafion, the adsorption energy of CO on Pt(111) catalyst increases by about 5 eV (the grater the adsorption energy, the better the CO poisoning resistance), which greatly increases the CO poisoning resistance of Pt catalyst. By further calculation, the better the adsorption performance of Nafion on Pt(111) surface, the stronger the anti-CO poisoning ability of Pt catalyst. [ABSTRACT FROM AUTHOR]

We have comparatively investigated the adsorption behaviors of CO, O2, and H2O on the B-CNT and Fe@B-CNT using density functional theory calculations. Our results reveal that the Fe atom is more likely to adsorb under the C1-B bond on the inner wall of B-CNT, and the adsorption abilities of CO, O2, and H2O onto the external surfaces of the B-CNT and Fe@B-CNT are in following: H2O@B-CNT > O2@B‑CNT > CO@B-CNT; CO@Fe@B-CNT > H2O@Fe@B-CNT > O2@Fe@B-CNT. The doping of B becomes the active site in B-CNT, and the metal confinement enhances the activity of B atom. The adsorption of CO, O2, and H2O has little effect on the structure of Fe@B-CNT. Thus, the metal confinement not only improves the activity of the catalyst, but also enhances the stability of the catalyst. [ABSTRACT FROM AUTHOR]

Single-atom confinement inside carbon nanotubes has attracted much attention in many fields. This class of materials may not only serve as a catalyst but also as a support material for certain reactions. In this paper, we have studied the single-walled carbon nanotubes (SWCNT), single vacancy defect (SV), and Stone–Wales defect (SW) carbon nanotubes with Fe, Co, and Ni atom by both inside and outside adsorption structures in density function theory (DFT). Our results reveal that the binding abilities of atomic Fe, Co, Ni onto the internal and external surfaces of the SWCNT, SV, and SW are in following orders by metals: Ni > Co > Fe. The adsorption energies of SV toward Fe, Co, and Ni are more stable than those of SWCNT and SW, which can be attributed to the three active carbon sites created by a C atom removing, while the SWCNT and SW demonstrate similar adsorption energy due to the similar structure. Generally, the stability of external adsorption structures is stronger than those of internal adsorption structures, but as for the SW, the stability of internal and external adsorption structures is close, which means that the defects have improved the confinement of carbon nanotubes to M (M = Fe, Co, Ni). [ABSTRACT FROM AUTHOR]

Objective: Previous studies showed that hypomethylating agents (HMAs) could alleviate acute graft- versus -host disease (aGvHD), but affect engraftment after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The combination of two different HMAs in lower doses might overcome this problem. This study aimed to evaluate the treatment effect of the combination of two HMAs—azacitidine (5-Aza) and histone H3K27 methyltransferase inhibitor 3-deazaneplanocin (DZNep)—for the prophylaxis of aGvHD after allo-HSCT and to explore the possible mechanisms. Methods: We first optimized the concentrations of individual and combinational 5-Aza and DZNep treatments to ensure no obvious toxicities on activated T cells by evaluating T-cell proliferation, viability, and differentiation. A mouse model of aGvHD was then established to assess the prophylactic efficacy of 5-Aza, DZNep, and their combination on aGvHD. The immunomodulatory effect on T cells and the hematopoietic reconstruction were assessed. Additionally, RNA sequencing (RNA-seq) was performed to identify the underlying molecular mechanisms. Results: Compared with single treatments, the in vitro application of 5-Aza with DZNep could more powerfully reduce the production of T helper type 1 (Th1)/T cytotoxic type 1 (Tc1) cells and increase the production of regulatory T cells (Tregs). In an allo-HSCT mouse model, in vivo administration of 5-Aza with DZNep could enhance the prophylactic effect for aGvHD compared with single agents. The mechanism study demonstrated that the combination of 5-Aza and DZNep in vivo had an enhanced effect to inhibit the production of Th1/Tc1, increase the proportions of Th2/Tc2, and induce the differentiation of Tregs as in vitro. RNA-seq analysis revealed the cytokine and chemokine pathways as one mechanism for the alleviation of aGvHD with the combination of 5-Aza and DZNep. Conclusion: The combination of 5-Aza and DZNep could enhance the prophylactic effect for aGvHD by influencing donor T-cell differentiation through affecting cytokine and chemokine pathways. This study shed light on the effectively prophylactic measure for aGvHD using different epigenetic agent combinations. [ABSTRACT FROM AUTHOR]

A large number of experiments show that PtCu catalyst has a good catalytic effect on methanol decomposition. Therefore, density functional theory (DFT) was used to further study the dehydrogenation of methanol catalyzed by PtnCum (n = 1–3, m = 0–2). The energy diagrams of O-adsorption path and H-adsorption path were drawn. By calculation, the Pt is the active site of the whole reaction process, and the barrier energy of the rate-determining step is 11.09 kcal mol−1 by Pt2Cu, which is lower than that of Pt3 and PtCu2. However, the complete dehydrogenation product of methanol, CO, is easier to dissociate from PtCu2 clusters than from Pt3 and Pt2Cu clusters. Therefore, Cu doping can improve the catalytic activity and anti-CO toxicity of Pt to a certain extent. [ABSTRACT FROM AUTHOR]

The superfamily Gelechioidea (Lepidoptera: Obtectomera) has a high species diversity. It consists of more than 18,400 described species and has a global distribution. Among it, large numbers of species were reported to be economically important to people's production and life. However, relationships among families or subfamilies in Gelechioidea have been exceptionally difficult to resolve using morphology or single gene genealogies. Multiple gene genealogies had been used in the molecular phylogenetic studies on Gelechioidea during the past years, but their phylogenetic relationships remain to be controversial mainly due to their limited taxa sampling relative to such high species diversity. In this paper, 89 ingroup species representing 55 genera are sequenced and added to the data downloaded from GenBank, and six species representing four closely related superfamilies are chosen as outgroup. The molecular phylogeny of Gelechioidea is reconstructed based on the concatenated data set composed of one mitochondrial marker (COI) and seven nuclear markers (CAD, EF‐1ɑ, GAPDH, IDH, MDH, RpS5, wingless). The phylogenetic results, taking into consideration of the comparative morphological study, show that the clade of Gelechioidea is strongly supported and separated from other superfamilies, which further proves its monophyly. Five families are newly defined: Autostichidae sensu nov., Depressariidae sensu nov., Peleopodidae sensu nov., Ashinagidae sensu nov. and Epimarptidae sensu nov. Meanwhile, a monophyletic "SSABM" clade considered to be closely related is proposed for the first time, consisting of Stathmopodidae, Scythrididae, Ashinagidae, Blastobasidae and Momphidae. Moreover, geometric morphometric analyses using merged landmark data set from fore and hind wings of 118 representative species are conducted. The phenetic tree shows that the monophyly and phylogenetic relationships correspond with the results of molecular phylogeny largely, which well proves its importance and potential application in both phylogenetic reconstruction and species identification. [ABSTRACT FROM AUTHOR]

The present paper is concerned with the oscillatory stability and selection condition of dendritic growth from a system of binary mixture with enforced flow. We consider the case of large Schmidt number (Sc>1) and obtain the uniformly valid asymptotic solution by following the approach of the interfacial wave (IFW) theory of dendritic growth developed by Xu in the 1990s [Phys. Rev. A 43, 930 (1991); Phys. Rev. E 53, 5051 (1996)]. The results obtained show that the oscillatory wave instability mechanism explored in the IFW theory remains in the case under study. The quantitative changes in the critical number of stability criterion and selected condition for the velocity of the dendrite tip affected by the strength of the enforced flow are given under various growth conditions and material properties. [ABSTRACT FROM AUTHOR]

We have comparatively investigated the adsorption behaviors of Sc atom on the external and internal surfaces of the pristine, Stone-Wales (SW), and single-vacancy (SV) defect nanotubes based on the density functional theory. Our results reveal that the stability of Sc atom onto the external and internal surfaces of the carbon nanotubes is in following orders by defect: SV>SW1>SW2>pristine (external surfaces), SV>SW2>SW1>pristine (internal surfaces). To explore the reactivity of Sc@CNT/SW/SV complexes which can serve as a gas sensor or a catalyst in direct methanol fuel cell (DMFC), the interaction between a CO molecule and Sc@CNT/SW/SV is also examined. The SV defect in carbon nanotubes can make the confined Sc atom with good CO adsorption property, while the confined Sc in the SW defect carbon nanotube has good anti-CO poisoning. By our studies, it plays an important guidance role in improving the activity of metal catalyst and the sensitivity and stability of metal particles to functional molecules, and provides the theoretical basis for designing new carbon nanotube-based metal catalyst. [ABSTRACT FROM AUTHOR]

Currently, two types of problems exist in the design of measurement matrices in compressed sensing. One is that random measurement matrices are difficult to be realized by hardware. The other is that the size of deterministic matrices which are based on polynomials or algebraic curves cannot be arbitrary. To cope with these problems, this paper introduced a measurement matrices construction method based on deterministic random sequences. The proof that the matrices satisfy the Restricted Isometry Property (RIP) was also given in the paper. In the simulation experiments, the proposed matrices were compared with Gaussian random matrices, Bernoulli matrices, sparse matrices and chaotic matrices. Experi-ment results show that the matrices designed by the proposed strategy have equal performance with other popular measurement matrices. Also, deterministic random matrices were used for speech compression and reconstruction. Subjective and objective evaluation results of speech quality both show that the proposed matrices exhibit excellent performance in speech reconstruction. [ABSTRACT FROM AUTHOR]

Background: The transmission of schistosomiasis japonica in a local setting is still poorly understood in the lake regions of the People's Republic of China (P. R. China), and its transmission patterns are closely related to human, social and economic factors. Methodology/Principal Findings: We aimed to apply the integrated approach of artificial neural network (ANN) and logistic regression model in assessment of transmission risks of Schistosoma japonicum with epidemiological data collected from 2339 villagers from 1247 households in six villages of Jiangling County, P.R. China. By using the back-propagation (BP) of the ANN model, 16 factors out of 27 factors were screened, and the top five factors ranked by the absolute value of mean impact value (MIV) were mainly related to human behavior, i.e. integration of water contact history and infection history, family with past infection, history of water contact, infection history, and infection times. The top five factors screened by the logistic regression model were mainly related to the social economics, i.e. village level, economic conditions of family, age group, education level, and infection times. The risk of human infection with S. japonicum is higher in the population who are at age 15 or younger, or with lower education, or with the higher infection rate of the village, or with poor family, and in the population with more than one time to be infected. Conclusion/Significance: Both BP artificial neural network and logistic regression model established in a small scale suggested that individual behavior and socioeconomic status are the most important risk factors in the transmission of schistosomiasis japonica. It was reviewed that the young population (≤15) in higher-risk areas was the main target to be intervened for the disease transmission control. Author Summary: Schistosomiasis japonica is one of the serious infectious diseases causing problems in public health in People's Republic of China (P.R. China). The prevalence of schistosomiasis japonica is easily rebounding in the lake regions due to unique environmental settings. By considering the importance in assessing the risk factors for transmission of schistosomiasis, we conducted an epidemiologic investigation of schistosomiasis in Jiangling County, a lake region of P.R. China. Results showed that the top risk factors included integration of water contact history and infection history, infection times, main lifestyle of water contact, main recreation of water contact, etc., illustrated by both back-propagation artificial neural network and multivariable logistic regression approaches. It was found that the population at age 15 or younger having one or two times of infections was the high-risk group in the study settings. We concluded that socioeconomic factors are far more important than environmental factors in the transmission of schistosomiasis at local settings or in a small scale in Jiangling County, P.R. China. [ABSTRACT FROM AUTHOR]

Background: The transmission of schistosomiasis japonica in a local setting is still poorly understood in the lake regions of the People's Republic of China (P. R. China), and its transmission patterns are closely related to human, social and economic factors. Methodology/Principal Findings: We aimed to apply the integrated approach of artificial neural network (ANN) and logistic regression model in assessment of transmission risks of Schistosoma japonicum with epidemiological data collected from 2339 villagers from 1247 households in six villages of Jiangling County, P.R. China. By using the back-propagation (BP) of the ANN model, 16 factors out of 27 factors were screened, and the top five factors ranked by the absolute value of mean impact value (MIV) were mainly related to human behavior, i.e. integration of water contact history and infection history, family with past infection, history of water contact, infection history, and infection times. The top five factors screened by the logistic regression model were mainly related to the social economics, i.e. village level, economic conditions of family, age group, education level, and infection times. The risk of human infection with S. japonicum is higher in the population who are at age 15 or younger, or with lower education, or with the higher infection rate of the village, or with poor family, and in the population with more than one time to be infected. Conclusion/Significance: Both BP artificial neural network and logistic regression model established in a small scale suggested that individual behavior and socioeconomic status are the most important risk factors in the transmission of schistosomiasis japonica. It was reviewed that the young population (#15) in higher-risk areas was the main target to be intervened for the disease transmission control. [ABSTRACT FROM AUTHOR]

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We study the phenomenon of spatial coherence resonance (SCR) on Hodgkin–Huxley (HH) neuronal networks that are characterized with information transmission delay. In particular, we examine the ability of additive Gaussian noise to optimally extract a particular spatial frequency of excitatory waves in diffusive and small-world networks on which information transmission amongst directly connected neurons is not instantaneous. On diffusively coupled HH networks, we find that for short delay lengths, there always exists an intermediate noise level by which the noise-induced spatial dynamics is maximally ordered, hence implying the possibility of SCR in the system. Importantly thereby, the noise level warranting optimally ordered excitatory waves increases linearly with the increasing delay time, suggesting that extremely long delays might nevertheless preclude the observation of SCR on diffusive networks. Moreover, we find that the small-world topology introduces another obstacle for the emergence of ordered spatial dynamics out of noise because the magnitude of SCR fades progressively as the fraction of rewired links increases, hence evidencing decoherence of noise-induced spatial dynamics on delayed small-world HH networks. Presented results thus provide insights that could facilitate the understanding of the joint impact of noise and information transmission delay on realistic neuronal networks. [ABSTRACT FROM AUTHOR]