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A series of cerium phosphate catalysts with different crystal phases were synthesized by hydrothermal method and co-precipitation method. Hexagonal cerium phosphate (CePO4-H) shows better NH3-SCR denitration activity than monoclinic cerium phosphate (CePO4-M) and mixed phases of CePO4-H and CePO4-M. Moreover, CePO4-H also exhibits excellent activity stability with stream time and cycle used stability. Various characterizations were carried out to explain the effects of different crystal phases of CePO4 on the activity. Among these catalysts, CePO4-H has much stronger surface acidity that is conducive to the adsorption and activation of NH3, and more surface adsorbed oxygen species that can effectively improve SCR activity. In situ DRIFTS were performed to investigate the adsorption and reaction of NH3 and NOx on CePO4-H and CePO4-M, and the results suggest that the better activity over CePO4-H follows mainly the E-R mechanism in the activity temperature window (300–500 oC) with 100% NO conversion.

Wireless Sensor Networks is a network system which is composed of one or more sinks and many sensor nodes in generally. The process of wireless communication exists path loss in the wireless channel, which can be affected by the distance between receiver and transmitter, the operating frequency or the other factors. It is especially vital for choosing the optimal relay nodes in the case of energy limitation. To emphasize the energy optimally, a method of relay nodes selection based on the energy model is proposed which is considering the effective data transmission and the energy consumption. Theoretical analysis and experiments show that the energy consumption of the next hop relay nodes is smaller.

Background Goose astrovirus (GoAstV) is an important pathogen that causes joint and visceral gout in goslings. It has been circulating in many provinces of China since 2017. Goose astrovirus genotypes 2 (GoAstV-2) is the main epidemic strain, and its high morbidity and mortality have caused huge economic losses to the goose industry. An accurate point-of-care detection for GoAstV-2 is of great significance. In this study, we developed a real-time reverse transcription recombinase polymerase amplification (RT-RPA) method for the on-site detection of GoAstV-2 infection. Results The real-time RT-RPA reaction was carried out at a constant temperature of 39°C, and the entire detection time from nucleic acid preparation to the end of amplification was only 25 min using the portable device. The results of a specificity analysis showed that no cross-reaction was observed with other related pathogens. The detection limit of the assay was 100 RNA copies/µL. The low coefficient of variation value indicated excellent repeatability. We used 270 clinical samples to evaluate the performance of our established method, the positive concordance rates with RT-qPCR were 99.6%, and the linear regression analysis revealed a strong correlation. Conclusions The established real-time RT-RPA assay showed high rapidity, specificity and sensitivity, which can be widely applied in the laboratory, field and especially in the resource-limited settings for GoAstV-2 point-of-care diagnosis.

Background. This study used a combination of network pharmacology and experimental confirmation to clarify the mechanism of the compound kidney-invigorating granule (CKG) in treating osteoporosis (OP). Methods. The main bioactive compounds and corresponding targets of CKG were collected and screened via the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), Yet another Traditional Chinese Medicine (YaTCM), and UniProt databases. Disease targets of OP were summarized in GeneCards and the Comparative Toxicogenomics Database (CTD). Targets of CKG for OP were obtained by Venn diagram. The protein-protein interaction (PPI) network was constructed by the STRING database and then screened for hub genes through Cytoscape 3.7.2 software. The Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment were analyzed and visualized by R software. Then, CB-Dock was used for molecular docking verification. Finally, we confirmed the antiosteoporosis effect of CKG through animal and cell experiments. Results. A total of 250 putative targets were obtained from 65 bioactive compounds in CKG. Among them, 140 targets were related to OP. Topological analysis of the PPI network yielded 23 hub genes. Enrichment analysis showed the targets of CKG in treating OP might concentrate on the MAPK signaling pathway, the TNF signaling pathway, the PI3K-Akt signaling pathway, etc. The results of molecular docking showed the bioactive components in CKG had good binding ability with the key targets. The experimental results showed that CKG-medicated serum had a promoting effect on proliferating hBMSCs, increasing the expression of AKT, PI3K, ERK1, and IkB in cells and decreasing the expression of IKK in cells. Conclusion. CKG has a complex of multicomponent, multitarget, and multipathway. This study lays the theoretical foundation for further in vitro and in vivo experimental studies and further expands the clinical applications of CKG.

The formation of K–O–Mn bond weaken the bond of Mn–O–Mn which increases oxygen species mobility leading to excellent catalytic oxidation performance over OMS-2 by introducing different amounts of K.

It is highly desirable but quite challenging to replace precious metals with cheaper elements in the catalytic selective hydrogenation of unsaturated aldehydes. Herein, we report the preparation of a series of CuxNi3-xAlOy mixed-metal oxides (x = 0.5, 1, 2) derived from CuxNi3-xAl hydrotalcite to be used as catalysts for the promotion of the selective hydrogenation of furfural (FAL) to furfuryl alcohol (FOL). It was found that the catalyst with the Cu2Ni1AlOy stoichiometry exhibited the best performance, with 98% FAL conversion and 99% selectivity toward FOL after 1.5 h at 120 °C and under a H2 pressure of 1.6 MPa, and also good reusability. On the basis of the combined results from catalyst characterization studies using XRD, H2-TPR, TEM, XPS, and in-situ FT-IR, it was concluded that the CuOx species on the surface of the CuxNi3-xAlOy catalysts can be reduced in situ to metallic copper during reaction, and that this Cu0 species is likely the responsible for the adsorption and conversion of FAL. The addition of Ni to these mixed-metal oxides helps disperse the Cu phase and hence make it easier to reduce and activate. It may also be that NiO can promote H2 dissociation to aid with the hydrogenation catalysis. Our work advances a new strategy for the design of simple, cheap, and efficient catalysts for the hydrogenation of FAL to FOL.

Catalytic oxidation is considered a high-efficient method to minimize efficiently toluene emission. It is still a challenge to improve the catalytic performance for toluene oxidation by modifying the surface properties to enhance the oxidation ability of catalyst. Herein, a series of CuaCo1−aOx (a = 0.1, 0.2, 0.4, 0.6) catalysts were synthesized via solvothermal method and applied for toluene oxidation. The effects of the Cu/Co ratio on the texture structure, morphology, redox property and surface properties were investigated by various characterization technologies. The Cu0.4Co0.6Ox catalyst with dumbbell-shaped flower structure exhibited much lower temperature of 50% and 100% toluene conversion and far higher reaction rate (13.96 × 10−2 μmol·g−1·s−1) at 220 °C than the Co based oxides in previous reports. It is found that the good activity can be attributed to the fact that the proper Cu/Co ratio can significantly improve the formation of more surface adsorbed oxygen and Co3+ species, leading to the much higher oxidation ability came from the strong interaction between Cu and Co oxides. It is suggested that toluene should be oxidized more rapidly to CO2 and H2O over the Cu0.4Co0.6Ox catalyst than Co3O4 based on the results of in situ DRIFTS.

Catalytic oxidation is considered as the most effective and economical method to remove low concentration volatile organic compounds (VOCs). Activation of oxygen to form active oxygen species on metal oxides catalyst plays a key role in the process. Three copper-manganese oxide catalysts with cubic Cu

The detection of indoor formaldehyde gas is important because of its highly toxic nature. Herein, the two-dimensional α-MoO3 nanosheets and three-dimensional α-MoO3 hierarchical flowers have been prepared by simple hydrothermal strategy and used as the formaldehyde sensing materials. Their microstructures, morphologies and gas sensing characteristics towards formaldehyde were studied. The test results exhibited that, at the optimal temperature of 250 °C, the sensor performances were enhanced due to the assembly of 2D nanosheets into 3D hierarchical structure. The improved properties were contributed to the formation of the hierarchical microstructure constructed by nanosheets. The hierarchical microstructure based gas sensor has significant potential in indoor air sensing application.

The Pt/(Fe, Mn/Co)-BTC catalysts were fabricated by a facile ultrasonic impregnation assisted hydrothermal polyol reduction method using first MIL-100(Fe, Mn/Co) MOFs as supports and tested for selective hydrogenation of furfural (FAL) to furfuryl alcohol (FOL). Various characterizations including XRD, TG, FT-IR, N2 physical adsorption, ICP-OES, SEM, TEM and XPS were applied for exploring structure changes and surface properties of the catalysts. Over 98% conversion of FAL and 99% selectivity to FOL were achieved over Pt/(Fe, Mn)-BTC and Pt/(Fe, Co)-BTC, moreover, Pt/(Fe, Co)-BTC showed higher turnover frequency (TOF) of 1,044 h−1 and better cycle stability, which are better than other catalysts prepared by using H2, NaBH4, and formaldehyde as reductants. Overall, the formation of highly dispersed small-sized Pt NPs (about 1.7 nm) with much higher content of surface Pt0 on the catalysts is the key of excellent hydrogenation activity due to the strong interaction between Pt NPs and the bimetallic supports.

Background: Despite some insurance plans now paying for home-based palliative care, recent reports have suggested that insurance coverage for palliative care may be insufficient in expanding patient access to home-based palliative care. Aim: To identify patients’ and caregivers’ perceived barriers to home-based palliative care and their recommendations for overcoming these barriers. Design: We conducted a qualitative study using semi-structured individual interviews. Our interview protocol elicited participants’ perspectives on home-based palliative care services; positive and negative aspects of the palliative program explanation; and suggestions for improving messaging around home-based palliative care. Setting/Participants: Twenty-five participants (patients, proxies, and their caregivers) who were eligible for a randomized controlled trial of home-based palliative care were interviewed by telephone. Results: Themes related to home-based palliative care referral barriers included reluctance to have home visits, enrollment timing, lack of palliative care knowledge, misconceptions about palliative care, and patients’ self-perceived health condition. Themes related to recommendations for overcoming these obstacles included ensuring that palliative care referrals come from healthcare providers or insurance companies and presenting palliative care services more clearly. Conclusion: Findings reinforce the need for additional palliative care education among patients with serious illness (and their caregivers) and the importance of delivering palliative care information and referrals from trusted sources.

Older adults have higher risk of experiencing medication related problems (MRPs), leading to increased morbidity, healthcare utilization, and mortality. Few studies have examined the relationship between non-native English speaking (NNES) and MRPs and their association with health service use. This study aimed to explore language disparities in MRPs and their relationship to emergency room (ER) visits among community-dwelling older adults. We used secondary enrollment data from a community medication program for older adults (N=180). We conducted linear regression to examine the relationship between NNES and MRPs, and logistic regression to explore the association between MRPs and ER visits. Generalized structural equation modeling (GSEM) with bootstrapping was used to test the indirect effect between NNES through MRPs to ER visits. The sample was diverse with 40% White, 30% Hispanic, 22% African American, and 8% of other races; 18% were non-native English speakers. Analysis showed NNES was associated with having 2.7 more MRPs than native English-speaking participants, while race was not significant, after controlling for covariates. Each additional MRP was associated with a 9% increased probability of having an ER visit. The GSEM results found a significant indirect effect between NNES through MRPs to ER visits (β, 0.27; 95% CI, 0.07 to 0.61). Although NNES was not directly related to ER visits, it may have inhibited the ability of Hispanics to read important medication instructions, contributing to their elevated risk of experiencing MRPs, thus indirectly increasing potential risks leading to ER visits. Further research is needed to better understand this relationship.

Health care costs remain high at the end of life. It is not known if there is a relationship between advance directive (AD) completion and hospital out-of-pocket costs. This analysis investigated whether AD completion was associated with lower hospital out-of-pocket costs at end of life.We used Health and Retirement Study participants who died between 2000 and 2014 (N = 9228) to examine the association between AD completion status and hospital out-of-pocket spending in the last 2 years of life through the use of a two-part model controlling for socioeconomic status, death-related characteristics and health insurance coverage.About 44% of decedents had completed ADs. Having an AD was significantly associated with $673 lower hospital out-of-pocket costs, with a higher magnitude of savings among younger decedents. Decedents who completed ADs 3 months or less before death had higher out-of-pocket costs ($1854 on average) than those who completed ADs more than 3 months before death ($1176 on average).AD completion was significantly associated with lower hospital out-of-pocket costs, with greater out-of-pocket savings among younger decedents. Early AD completers experienced lower costs than decedents who completed ADs closer to death.

Precious metals have been shown to play a vital role in the selective hydrogenation of α,β-unsaturated aldehydes, but still suffer from challenges to control selectivity. Herein, we have advanced the design of catalysts made out of Pt–Co intermetallic nanoparticles (IMNs) supported on a MIL-101(Cr) MOF (3%Pty%Co/MIL-101(Cr)), prepared by using a polyol reduction method, as an effective approach to enhance selectivity toward the production of α,β-unsaturated alcohol, the desired product. XRD, N2 adsorption–desorption, FTIR spectroscopy, SEM, TEM, XPS, CO adsorption, NH3-TPD, XANES and EXAFS measurements were used to investigate the structure and surface properties of our 3%Pty%Co/MIL-101(Cr) catalysts. It was found that the Co-modified 3%Pty%Co/MIL-101(Cr) catalysts can indeed improve the hydrogenation of cinnamaldehyde (CAL) to cinnamyl alcohol (COL), reaching a higher selectivity under mild conditions than the monometallic Pt/MIL-101(Cr) catalysts: 95% conversion of CAL with 91% selectivity to COL can be reached with 3%Pt3%Co/MIL-101(Cr). Additionally, high conversion of furfural (97%) along with high selectivity to furfural alcohol (94%) was also attained with the 3%Pt3%Co/MIL-101(Cr) catalyst. The enhanced activity and selectivity toward the unsaturated alcohols are attributed to the electronic and geometric effects derived from the partial charge transfer between Co and Pt through the formation of uniformly dispersed Pt–Co IMNs. Moreover, various characterization results revealed that the addition of Co to the IMPs can promote the Lewis acid sites that facilitate the polarization of the charge-rich CO bonds and their adsorption via their oxygen atom, and also generate new interfacial acid sites.

Unstable pressure and u-equilibrium states are introduced and investigated for a partially hyperbolic diffeomorphism f. We define the unstable pressure $P^{u}(f, \varphi )$ of f at a continuous function $\varphi $ via the dynamics of f on local unstable leaves. A variational principle for unstable pressure $P^{u}(f, \varphi )$ , which states that $P^{u}(f, \varphi )$ is the supremum of the sum of the unstable entropy and the integral of $\varphi $ taken over all invariant measures, is obtained. U-equilibrium states at which the supremum in the variational principle attains and their relation to Gibbs u-states are studied. Differentiability properties of unstable pressure, such as tangent functionals, Gateaux differentiability and Fréchet differentiability and their relations to u-equilibrium states, are also considered.

The addition of a suitable co-catalyst is an encouraging way to enhance the catalytic performance of Pd based catalyst with low content. Herein, we describe an easy synthesis of Mo2N-TiO2 with well-dispersed Mo2N nanoparticles through one pot evaporation-induced self-assembly and nitridation treatment method. Moreover, a green bio-reductive approach with Catalpa Fruit (CF) extract was adopted to fabricate Pd/Mo2N-TiO2 catalysts for promoting selective hydrogenation of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) as model reaction. Among these Pd/Mo2N-TiO2 catalysts, 0.8 wt%Pd/Mo2N-TiO2 exhibits significantly high catalytic activity for selective hydrogenation of various nitrophenols and cinnmaldehyde. Importantly, the catalytic activity of the catalyst prepared by the reduction method of the CF extract is higher than that prepared by the reduction method of NaBH4. A serials of characterization, including XRD, N2 adsorption–desorption, TEM, XPS, CO chemisorption and CO-FTIR etc., was carried out to investigate the influence of the prepared method on the surface Pd species and activity. The high performance can be attributed to the specific nanostructure characteristics of the catalyst and the good synergistic effect between Pd and Mo2N, improving the dispersion of Pd nanoparticles atoms and the exposure of more active Pd atoms (surface Pd0 species) on 0.8 wt%Pd/Mo2N-TiO2 due to the CF extract as reductant.

In this paper, the pressure of a potential via the dynamics of preimage structure are investigated for noninvertible systems and the properties for the related equilibrium states are considered. For a continuous map on a compact metric space, a notion of preimage pressure via the preimages of single points is introduced, and then some fundamental properties are considered and a variational principle is established for the system with uniform separation of preimages. For a C 1 -partially hyperbolic endomorphism on a closed Riemannian manifold, a notion of stable pressure via the preimages of local stable manifolds is introduced and a corresponding variational principle is established. Moreover, equilibrium states and tangent functionals for pointwise preimage pressures and stable pressures are also considered. By describing the set of equilibrium states and tangent functionals and a sense of continuous dependence of equilibrium states with respect to the potential, we prove that the continuous potentials with unique equilibrium state form a dense G δ set. In addition, for any finite collection of ergodic measures, we can find a continuous potential such that its set of equilibrium states contains the given set.

The adsorption and delivery of reactants to active sites are the first two steps of catalytic reactions, however, which receive less attention compared with the design of highly active sites. Herein, we provide an improvement of the two crucial steps by designing perovskite oxides-carbon composites (LaFeO3_N) for catalytic transfer hydrogenation (CTH) of furfural to furfuryl alcohol. The principle is to ensure that the reactants can be timely supplied to the active sites for reaction. Indeed, the reaction rate over LaFeO3_N increases tremendously to 5.17 mmol g−1 h−1 that is 6 times higher than that over LaFeO3_A (0.81 mmol g−1 h−1) without carbon material. The results suggest that LaFeO3_N can improve the migration of reactants from solution to LaFeO3 active sites due to the presence of carbon, which has the ability to absorb and deliver the reactants. Effects of carbon content and carbon texture on the reaction are fully investigated. The current strategy of improving the catalytic performances of perovskite oxides can be easily applied to other catalytic systems with low surface area.

For non-invertible dynamical systems, we investigate how ‘non-invertible’ a system is and how the ‘non-invertibility’ contributes to the entropy from different viewpoints. For a continuous map on a compact metric space, we propose a notion of pointwise metric preimage entropy for invariant measures. For systems with uniform separation of preimages, we establish a variational principle between this version of pointwise metric preimage entropy and pointwise topological entropies introduced by Hurley [On topological entropy of maps. Ergod. Th. & Dynam. Sys.15 (1995), 557–568], which answers a question considered by Cheng and Newhouse [Pre-image entropy. Ergod. Th. & Dynam. Sys.25 (2005), 1091–1113]. Under the same condition, the notion coincides with folding entropy introduced by Ruelle [Positivity of entropy production in nonequilibrium statistical mechanics. J. Stat. Phys.85(1–2) (1996), 1–23]. For a $C^{1}$-partially hyperbolic (non-invertible and non-degenerate) endomorphism on a closed manifold, we introduce notions of stable topological and metric entropies, and establish a variational principle relating them. For $C^{2}$ systems, the stable metric entropy is expressed in terms of folding entropy (namely, pointwise metric preimage entropy) and negative Lyapunov exponents. Preimage entropy could be regarded as a special type of stable entropy when each stable manifold consists of a single point. Moreover, we also consider the upper semi-continuity for both of pointwise metric preimage entropy and stable entropy and give a version of the Shannon–McMillan–Breiman theorem for them.

MoaMnTi10Ox (a= 0.2, 0.4, 0.6 and 0.8) catalysts have been prepared by sol-gel and applied in the NH3-SCR of NO reaction. These catalysts were characterized by XRD, H2-TPR, NH3-TPD, XPS and in situ DRIFTS. Among the MoaMnTi10Ox catalysts, Mo0.6MnTi10Ox exhibits the excellent NH3-SCR performance with a broaden activity temperature window even in presence of 5 vol.% H2O, together with an excellent resistance of H2O and SO2. Compared with MnTi10Ox, the Mo addition leads to the reduction of redox ability, improvement of the surface acid sites and inhibition of NO adsorption. A serial of characterizations confirms that the synergistic effect between redox property and surface acidity plays a key role in the much better NH3-SCR activity over Mo0.6MnTi10Ox. Furthermore, the in situ DRIFTS studies reveal the NH3-SCR reaction is following the E-R mechanism over Mo0.6MnTi10Ox at 210 °C. In addition, the effects of H2O on the NH3-SCR reaction are investigated by in situ DRIFTS.

To save time and economic cost of the synthesis of SAPO-34 zeolites, the effects of hydrothermal time on the structure and methanol-to-olefin (MTO) catalytic activity of SAPO-34 zeolites were investigated in detail. A series of SAPO-34 zeolites (SAPO-34-x h, x = 3, 4, 8, 12, 24 and 48) were obtained using the traditional hydrothermal method by changing the synthesis time at 210 °C. The obtained catalysts were characterized by XRD, N2 adsorption–desorption, SEM, TG-DTA, ICP, 29Si and 27Al MAS NMR and NH3-TPD techniques. Among these samples, SAPO-34-4 h with a higher Si/(Si + Al + P) ratio shows a much longer lifetime (518 min) and higher light olefin selectivity (82.0%) in the MTO reaction, which can be attributed to the unique Si distribution and low acidity. Moreover, the SAPO-34-4 h sample can maintain good MTO performance even under long time storage without complicated processing or after several cycles of regeneration. This facile synthesis procedure may be beneficial for large scale industrial catalyst production because of its short synthesis time.