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Solvothermal reactions of Co(NO3)2·6H2O, 3-amino-1,2,4-triazole, and 1,2,4,5-benzenetetracarboxylic acid afforded a Co-MOF: {[Co2(Hatz)(bta)]·H2O}n. Furthermore, a unique metal–organic-framework-ba...

As a stable chemical material, polypropylene (PP) micro-nanofibrous membranes are widely used in medical and health care. However, PP fibrous membranes with single nano scale diameter are conducive to high packing density, which results in large flow resistance across the membrane. Therefore, to improve the material’s water and air permeability, polyethylene glycol (PEG), an incompatible polymer with PP, was introduced by blending in a modified method using a melt blowing process. This proposed approach allows large 10 um diameter fibers to be entangled with fine 300 nm diameter fibers to produce highly porous binary structured fibrous membranes with small pore size. Because of its binary structure, the air permeability in the material reached 569.56 mm/s and the water vertical velocity was 70.15 mm/s. Additionally, the three-dimensional numerical calculations suggested that the high porosity and binary structure were key to enhancing water permeability in the fibrous membranes. These binary structured micro-nanofibrous membranes are expected to be used for filtration, separation, health care, oil/water separation, medical wound dressings, and other applications.

Polymorphism has attracted significant attention in the area of pharmaceutical chemistry and materials chemistry. For energetic materials, polymorphism may affect their physical performances such a...

Our aim was to study whether radial pulse wave signals can improve the risk prediction of incident hypertension and are associated with its concomitant metabolic risk factors beyond the traditional cardiovascular risk factor Ba-PWV. By enrolling 523 Chinese subjects in this study, linear and stepwise regression analysis was performed to assess the association of radial artery pulse wave signals and Ba-PWV with blood pressure and its related metabolic risk factors such as fasting plasma glucose (FPG), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and uric acid (UA). The area under the receiver-operating characteristic curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were calculated by risk assessment plot to compare the discriminative ability among models with and without radial artery pulse wave signals. After adjusting related confounding factors, radial artery pulse wave variable h3/h1 was selected as the sensitive influential factor for blood pressure. Moreover, a new model with h3/h1 had a higher AUC than the reference model without it (0.86 vs 0.84; P=0.030). And the NRI and IDI for the new model was 50.0% (P=0.017) and 3.16% (P=0.044), respectively. In addition to Ba-PWV, we found that the decrease of t4, t5, and h5 might be associated with higher FPG, TC, LDL-C, and UA and lower HDL-C. This research might provide a valuable additional tool for remote wearable monitoring of radial artery pulse wave signals in hypertension risk evaluation and management.

Fused heterocyclic energetic cation was rarely reported despite the development of energetic cation has attracted increasing attention in recent years. In this work, a new 1H-imidazo[4,5-d]pyridazi...

Polypropylene (PP) fibrous membranes are widely used in medical and healthcare due to its sustainability. However, pristine PP fibrous membranes show poor flexibility, which limits their advanced functional application in medical and healthcare. Therefore, to improve the flexibility of PP fibrous membranes, propylene-based elastomer (PBE), a copolymer compatible with PP, was introduced by using the melt blowing technique in this study. The SEM images show that the PP/PBE fibrous membrane samples expressed a binary structured network morphology consisting of fibers with a diameter distribution ranging from 0.4 to 15 µm. With an increase in PBE mass ratio from 15 to 80 wt%, the frequency of fibers with a diameter 3/m2 · h as the mass per unit area of the samples decreased from 129.9 to 40.1 g/m2. This work provides an alternate method for producing flexible fibrous membranes that have potential for application in items such as surgical gown cuffs, bandages, and face mask ear loops.

In the current study, we have successfully prepared two new Yb(III)-based coordination polymers with the chemical formulae of {[Yb(cptz)2(H2O)4]·NO3}n (1, Hcptz = (4-carboxylphenyl)-3-(prazin-2-yl)...

Producing acetaldehyde, an important industrial chemical, by direct catalytic non-oxidative dehydrogenation of ethanol presents many advantages over current production methods, including generating hydrogen. However, a stable, active, and selective catalyst is currently unavailable. This work demonstrates that the high activity and selectivity of nanoporous (np) NiCu for this reaction can be stabilized by keeping the catalyst in a metastable (“kinetically trapped”) state. Using a combination of in situ ambient-pressure and ex situ X-ray photoelectron spectroscopy, environmental transmission electron microscopy, and density functional theory calculations enabled correlating changes in surface composition with the changes in activity and stability upon treatment of np NiCu with H2 and O2. Reduction of Ni-doped nanoporous Cu by H2 exposure enhanced the initial activity but led to complete catalyst deactivation within ∼40 hours. In contrast, O2 pretreatment of the same catalyst increased both activity and long-term stability, with only 15% activity loss over 40 hours. The stability of np NiCu as a catalyst inversely correlates with the amount of metallic Ni at the surface, which is enriched by the H2 pretreatment, while the O2 pretreatment leads to a kinetically trapped Ni2+ subsurface state. This work emphasizes that detailed understanding of pretreatment-induced nanoscale structural and compositional changes is necessary to optimize catalyst performance.

Multi-functional membranes with high permeance and selectivity that can mimic nature's designs have tremendous industrial and bio-medical applications. Here, we report a novel concept of a 3D nanometer (nm)-thin membrane that can overcome the shortcomings of conventional membrane structures. Our 3D membrane is composed of two three-dimensionally interwoven channels that are separated by a continuous nm-thin amorphous TiO2 layer. This 3D architecture dramatically increases the surface area by 6000 times, coupled with an ultra-short diffusion distance through the 2–4 nm-thin selective layer that allows for ultrafast gas and water transport, ∼900 l m−2 h−1 bar−1. The 3D membrane also exhibits a very high ion rejection (R ∼ 100% for potassium ferricyanide) due to the combined size- and charge-based exclusion mechanisms. The combination of high ion rejection and ultrafast permeation makes our 3DM superior to the state-of-the-art high-flux membranes whose performances are limited by the flux-rejection tradeoff. Furthermore, its ultimate Li+ selectivity over polysulfide or gas can potentially solve major technical challenges in energy storage applications, such as lithium–sulfur or lithium–O2 batteries.

A mixed-ligand strategy has been used to construct stable luminescent coordination polymers (CPs). An ultra-stable Zn(ii) coordination polymer, [Zn(H3tpb)(Hbtc)]n (1) was hydrothermally synthesized by employing a new tripodal pyrazole ligand H3tpb and a classical carboxylic ligand H3btc (H3tpb = 1,3,5-tris(pyrazolyl)benzene, H3btc = 1,3,5-benzenetricarboxylic acid). Complex 1 exhibits a 2D sql network. Importantly, 1 not only possesses excellent thermal stability but also shows superior chemical stability in terms of water resistance, acid/base aqueous solutions tolerance (pH = 2-12), and organic solvents resistance. This excellent structural stability was further illustrated from the perspective of thermal decomposition kinetics. The luminescence properties were investigated, showing that complex 1 displays high sensitivity and selectivity for detecting Fe3+ and Cr2O72- ions in aqueous solutions via luminescence quenching effects.

As a virtual digital model that can reflect physical entities or systems, digital twins are revolutionizing industry. The first prerequisite for the construction of digital twins is the establishment of high-precision and complex entities or system models. A 47-components numerical system is established for the core engine test rig main test system by using the finite volume modularization modeling method. A comprehensive solution to the system-level valve-spool/orifice throttling modeling, the key issue of the fluid pipeline system modeling, is presented, and the algorithms of throttling and mixing are deepened and expanded. The full-process simulation study on two tests of normal-temperature 1400 s and low-temperature 1240 s shows that the combined regulation of five regulator valves and the change of cold source directly decide dynamic change of the system in each stage; the simulation reveals the phenomena such as the gas cylinder cooling with deflation, the air cooling when expanding from main pipeline to two branch pipelines, shunting flow by branch pipeline, and the cold and hot gases mixing; the overall variation trends of the simulation curves are consistent with those of all the experimental curves of the test rig normal-temperature/low-temperature air supply lines, exhaust bypass, and engine main line in two operating conditions, and the maximum error between simulation curves and test curves of pressure, total pressure, and total temperature is less than 12%. The numerical system can be used for the construction of virtual models of digital twins, and the modeling method provides a feasible solution to the key technology of digital twins.

Gradual riparian wetland drying is increasingly sensitive to global warming and contributes to climate change. Riparian wetlands play a significant role in regulating carbon and nitrogen cycles. In this study, we analyzed the emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) from riparian wetlands in the Xilin River basin to understand the role of these ecosystems in greenhouse gas (GHG) emissions. Moreover, the impact of the catchment hydrology and soil property variations on GHG emissions over time and space was evaluated. Our results demonstrate that riparian wetlands emit larger amounts of CO2 (335–2790 mgm-2h-1 in the wet season and 72–387 mgm-2h-1 in the dry season) than CH4 and N2O to the atmosphere due to high plant and soil respiration. The results also reveal clear seasonal variations and spatial patterns along the transects in the longitudinal direction. N2O emissions showed a spatiotemporal pattern similar to that of CO2 emissions. Near-stream sites were the only sources of CH4 emissions, while the other sites served as sinks for these emissions. Soil moisture content and soil temperature were the essential factors controlling GHG emissions, and abundant aboveground biomass promoted the CO2, CH4, and N2O emissions. Moreover, compared to different types of grasslands, riparian wetlands were the potential hotspots of GHG emissions in the Inner Mongolian region. Degradation of downstream wetlands has reduced the soil carbon pool by approximately 60 %, decreased CO2 emissions by approximately 35 %, and converted the wetland from a CH4 and N2O source to a sink. Our study showed that anthropogenic activities have extensively changed the hydrological characteristics of the riparian wetlands and might accelerate carbon loss, which could further affect GHG emissions.

A rich variety of smart materials developed via supramolecular assembly strategies have been introduced in the past decades. However, most materials reside in the thermodynamic equilibrium state, opposed to those nonequilibrium structures with sophisticated functions that are observed in living systems. To develop advanced synthetic systems, chemists have begun to focus on how to use strategies similar to those used in biological systems for fabricating artificial out‐of‐equilibrium systems. Heretofore, a rich variety of artificial out‐of‐equilibrium systems have been developed. In this review, we have summarized the recent progress of artificial out‐of‐equilibrium systems and categorized them in terms of the chemical fuel used, including adenosine triphosphate (ATP), acid/base, carbodiimide reagents, and many others. For these self‐assembling systems, their design strategies, potential applications, as well as advantageous features have been discussed. At the end of this review, the remaining challenges and an outlook of the chemical‐fuel‐driven out‐of‐equilibrium systems were also discussed. It is believed that this review has provided some insights and could be useful for those who are interested in the out‐of‐equilibrium supramolecular assembling systems and their subsequent constructing strategies for various transient materials.

Various sensing platforms based on molecular or nanosystems are widely exploited through molecular diversity and specific recognition. However, it is extremely challenging to develop systems with tunable sensing ability and utilize the systems as information carriers/covers for communication and safety. Herein, DNA nanosensing systems based on cobalt oxyhydroxide (CoOOH) nanosheets were constructed for tunable detection and valence distinction of metal ions, molecular crypto-steganography, and information coding. CoOOH nanosheets absorb fluorescence-labeled single-stranded DNA with different bases and lengths, resulting in fluorescence quenching. The binding priority of bases with CoOOH nanosheets was guanine (G) > cytosine (C) > adenine (A) ≈ thymine (T) and the short chain excelled long chain. Due to the differences in the interaction among CoOOH, DNA, metal ions and variability of DNA bases, various DNA−CoOOH nanosystems have significantly different selective response patterns (that is selectivity) to metal ions and tunable linear ranges to Fe3+, Hg2+, Cr3+. Interestingly, by utilizing their molecular diversity, recognition, selective patterns, DNA−CoOOH sensing systems can be served as doubly cryptographic and steganographic systems to implement information encoding, encryption, and hiding and to reversely improve the selectivity of metal ions. This study provides an idea and platform for adjustable detection and valence distinction of metal ions, and gives a set of “molecular programming languages” for designing intelligent programmable sensing and molecular information communication and safety systems.

Three-dimensional porous flow-through electrodes promise the realization of higher current densities in the electrochemical carbon dioxide reduction reaction (CO2RR) by overcoming mass-transport li...

Nucleotide synthesis is essential to proliferating cells, but the preferred precursors for de novo biosynthesis are not defined in human cancer tissues. We have employed multiplexed stable isotope-resolved metabolomics to track the metabolism of [(13)C(6)]glucose, D(2)-glycine, [(13)C(2)]glycine, and D(3)-serine into purine nucleotides in freshly resected cancerous and matched noncancerous lung tissues from nonsmall cell lung cancer (NSCLC) patients, and we compared the metabolism with established NSCLC PC9 and A549 cell lines in vitro. Surprisingly, [(13)C(6)]glucose was the best carbon source for purine synthesis in human NSCLC tissues, in contrast to the noncancerous lung tissues from the same patient, which showed lower mitotic indices and MYC expression. We also observed that D(3)-Ser was preferentially incorporated into purine rings over D(2)-glycine in both tissues and cell lines. MYC suppression attenuated [(13)C(6)]glucose, D(3)-serine, and [(13)C(2)]glycine incorporation into purines and reduced proliferation in PC9 but not in A549 cells. Using detailed kinetic modeling, we showed that the preferred use of glucose as a carbon source for purine ring synthesis in NSCLC tissues involves cytoplasmic activation/compartmentation of the glucose–to–serine pathway and enhanced reversed one-carbon fluxes that attenuate exogenous serine incorporation into purines. Our findings also indicate that the substrate for de novo nucleotide synthesis differs profoundly between cancer cell lines and fresh human lung cancer tissues; the latter preferred glucose to exogenous serine or glycine but not the former. This distinction in substrate utilization in purine synthesis in human cancer tissues should be considered when targeting one-carbon metabolism for cancer therapy.

Polyethylene glycol (PEG) was inserted into polypropylene (PP) in one-step melt blowing process to strengthen the filtration quality of the melt-blown nonwovens. The micro-nanofiber nonwovens with branch structure were fabricated by controlling the ratio of PEG in blend and process parameters in melt blowing process. The results showed that nanofibers with the diameter range of less than 800 nm were interspersed among microfibers, which demonstrated the laminated structure in thickness direction and quasi-continuous branch structure in horizontal direction. Furthermore, as the PEG ratio increasing from 0% to 15%, the ratio of fibers with diameter of 1500 nm increased from 37.50% to 231.82%. The filtration efficiency of the nonwovens followed typical behavior for the particles of 0.26 μm at air velocities of 0.05–0.142 m/s. The quality factor displayed an escalating trend with the increase of PEG ratio from 0% to 12% and achieved a maximum value of 0.02614 Pa−1 at the airflow rate of 0.053 m/s. Furthermore, the mechanism of formation of branch networks in nonwovens and its filter efficiency were discussed in detail. This work provides the feasibility of fast preparation of micro-nanofiber nonwovens with branch networks under high effective air filtration. Keywords: Nonwoven, Porous materials, Embedded, Air filtration, Micro-nanofiber

Dicarbohydrazide bis[3-(5-nitroimino-1,2,4-triazole)] (DCBNT) was firstly synthesized by ion exchange and salt formation reaction. A combination of single-crystal X-ray diffraction (SXRD), FTIR, 1H NMR, 13C NMR, and elemental analysis was utilized to analyze the structure and composition of DCBNT. DCBNT exhibits a high detonation velocity of 9234.87 m s−1 and a detonation pressure of 31.73 GPa as calculated by EXPLO5 v6.02 program. In addition, the sensitivities (impact sensitivity >40 J, H50 = 90 cm, and friction sensitivity = 216 N) and thermal stability (>230 °C) of DCBNT were investigated. Moreover, we measured the solubility of DCBNT in 12 common solvents by a polythermal method system which demonstrates its poor solubility in common organic solvents and water. These excellent physicochemical properties make DCBNT an environmentally friendly, low-sensitivity and high-energy explosive.

Background Gastric cancer (GC) derived exosomes (Exos) aggravate GC development by facilitating M2 macrophage polarization and long non-coding RNA (lncRNA) HCG18 was highly expressed in GC. This study aimed to investigate whether the exosomal lncRNA HCG18 regulated the M2 macrophage polarization in GC and the possible mechanism. Methods The isolated GC cells (GCCs)-Exos were identified using transmission electron microscopy, Nanoparticle Tracking Analysis and Western blot. The GCCs-Exos function was verified by enzyme-linked immunosorbent assay and flow cytometry. Meanwhile, the exosomal lncRNA HCG18 function was determined using thein vitro assays. Furthermore, the underlying mechanism of the exosomal lncRNA HCG18 that regulated M2 macrophage polarization in GC was investigated using dual-luciferase reporter gene assay and RNA pull-down. Results After the validation of GCCs-Exos, the GCCs-Exos facilitated the M2 macrophage polarization. The in vitro assays confirmed that the exosomal lncRNA HCG18 positively regulated the M2 macrophage polarization. Mechanistically, lncRNA HCG18 bound to miR-875-3p, miR-875-3p bound to KLF4. Furthermore, GCCs-exosomal lncRNA HCG18 elevated the KLF4 expression by decreasing miR-875-3p in macrophages to facilitate M2 macrophage polarization, thus alleviating GC. The in vivo assays clarified that the GCCs-exosomal lncRNA HCG18 restrained the tumor growth of GC induced by M2 macrophages. Conclusion GCCs-exosomal lncRNA HCG18 elevated KLF4 expression by decreasing miR-875-3p in macrophages to facilitate the M2 macrophage polarization.

Septic cardiomyopathy is a common complication of severe sepsis, which is one of the leading causes of death in intensive care units. Therefore, finding an effective therapy target is urgent. Neferine is an alkaloid extracted from the green embryos of mature seeds of Nelumbo nucifera Gaertn., which has been reported to exhibit various biological activities and pharmacological properties. This study aims to explore the protective effects of neferine against lipopolysaccharide (LPS)-induced myocardial dysfunction and its mechanisms. The LPS-induced cardiac dysfunction mouse model was employed to investigate the protective effects of neferine. In this study, we demonstrated that neferine remarkably improved cardiac function and survival rate and ameliorated morphological damage to heart tissue in LPS-induced mice. Neferine also improved cell viability and mitochondrial function and reduced cell apoptosis and the production of reactive oxygen species in LPS-treated H9c2 cells. In addition, neferine significantly upregulated Bcl-2 expression and suppressed cleaved caspase 3 activity in LPS-induced mouse heart tissue and H9c2 cells. Furthermore, neferine also upregulated the phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin (PI3K/AKT/mTOR) signaling pathway in vivo and in vitro. Conversely, LY294002 (a PI3K inhibitor) reversed the protective effect of neferine in LPS-induced H9c2 cells. Our findings thus demonstrate that neferine ameliorates LPS-induced cardiac dysfunction by activating the PI3K/AKT/mTOR signaling pathway and presents a promising therapeutic agent for the treatment of LPS-induced cardiac dysfunction.

Background: How bone properties would change after exercise intervention in patients with comorbidities are largely unknown. This study investigated the impact of Nordic walking on bone properties in postmenopausal women with pre-diabetes and non-alcohol fatty liver disease (NAFLD).Methods: The study is a part of a large randomized controlled trial. Of the eligible participants, 63 postmenopausal women (aged 50-65 years) with prediabetes and NAFLD participated in either a progressive supervised Nordic walking training (60-75% VO2max intensity), 2-3 times/week, 30-60 min/sessions for 8.6-month (AEx, n=33), or maintained their daily lifestyle during intervention (Con, n=30). Bone mineral content (BMC) and density (BMD) of the whole body (WB), total femur (TF), femoral neck (FN) and lumbar spine (L2-4) were assessed by a dual-energy X-ray absorptiometry. Venous blood samples were analyzed for serum osteocalcin, pentosidine and receptor activator of nuclear factor kappa-B ligand (RANKL) levels by ELISA assay. Results: After 8.6-month intervention, the AEx group maintained their BMCTF, BMDTF, BMCL2-4 and BMDL2-4, and increased their BMCFN (pTF (pTF (pL2-4 (pL2-4 (p=0.013). Decreased pentosidine was correlated with increased BMCWB (=-0.352, p=0.019). The intervention has no significant effect on osteocalcin and RANKL. Conclusions: Our results suggest that Nordic walking is effective in preventing bone loss among postmenopausal women with pre-diabetes and NAFLD. Changing of bone mass is associated with changing of pentosidine. However, this effect is not associated with osteocalcin and RANKL.Trial registration: ISRCTN registry, ISRCTN 42622771, registered 23 April 2013, https://www.isrctn.com/

In the present study, a methanogenic alkane-degrading (a mixture of C9 to C12n-alkanes) culture enriched from production water of a low-temperature oil reservoir was established and assessed. Significant methane production was detected in the alkane-amended enrichment cultures compared with alkane-free controls over an incubation period of 1 year. At the end of the incubation, fumarate addition metabolites (C9 to C12 alkylsuccinates) and assA genes (encoding the alpha subunit of alkylsuccinate synthase) were detected only in the alkane-amended enrichment cultures. Microbial community analysis showed that putative syntrophic n-alkane degraders (Smithella) capable of initiating n-alkanes by fumarate addition mechanism were enriched in the alkane-amended enrichment cultures. In addition, both hydrogenotrophic (Methanocalculus) and acetoclastic (Methanothrix) methanogens were also observed. Our results provide further evidence that alkanes can be activated by addition to fumarate under methanogenic conditions.

Etched aluminum foil for aluminum electrolytic capacitor was first boiled in water for different time to form hydrous film on Al foil and then anodized in H3BO4 solution at 530 V to form anodic oxide barrier film as insulating dielectric layer. The obtained films were characterized by field-emission scanning electron microscopy, transmission electron microscope and X-ray diffraction for surface morphology, microstructure and crystallinity examination. Small-current charging, LCR meter and electrochemical impedance spectroscopy were exploited to measure the propertied of the anodized oxide film such as withstanding voltage (Uw), specific resistance (Rox) and specific capacitance (Cs and Cox) for its electrochemical performance. The results show that the hydrous film is pseudoboehmite (PB) with a dense inner layer and a fibrous outer layer. The crystallinity of the PB film increases with hydration time. During anodization, the PB film was transformed into anodic oxide (γ′-Al2O3) barrier film. Prolonging hydration time promotes transformating PB into γ′-Al2O3 and improves the crystallinity of the barrier film, leading to increase in Cs and Cox and decrease in Rox and Uw.

A novel carbon-supported cyanogel (C@cyanogel)-derived strategy is used to synthesize an intermetallic Pd3Fe/C compound of the desired ordered Pd3Fe phase with a small particle size. The novelty of this work lies in using carbon-supported K2PdIICl4/K4FeII(CN)6 cyanogel as a reaction precursor, generated through the substitution of two chloride ligands by the nitrogen ends of the cyanide ligands on the metal center. The inherent nature of cyanogels can effectively suppress the movement of Pd0 and Fe0 nuclei in the crystal, benefiting the formation of the intermetallic, which is otherwise challenging via traditional synthesis techniques. The ordered Pd3Fe/C catalyst exhibits excellent catalytic activity and good cycle stability for the formic acid oxidation (FAO) reaction relative to the properties of disordered Pd3Fe/C and commercial Pd/C catalysts, demonstrating that the ordered Pd3Fe/C is a promising replacement for commercial Pd-based catalysts. The outstanding performance can be ascribed to the full isolation of active sites in the ordered Pd3Fe structure and the modified electronic structure of the active components. This work provides an effective and novel route to obtain Pd-based intermetallic compounds with potential applications in a wide range of electrocatalysis.

Gold is examined here as an alternative to copper for the selective dehydrogenation of ethanol to acetaldehyde and hydrogen. Despite its high selectivity, gold is only active at temperatures higher than 250 °C for this reaction. We demonstrate that addition of a small amount of Ni on either supported or unsupported Au surfaces induces resistance to sintering, along with a beneficial effect on the catalytic activity. NiAu alloys prepared here with Ni as the minority component to the limit of atomic dispersion in the gold surfaces, catalyze the reaction beginning below 150 °C. A significant decrease of the apparent activation energy from 96 ± 3 kJ/mol for the monometallic Au to 59 ± 5 kJ/mol for the alloy was found. The Ni dispersion and concentration as a function of gas environment was followed by in situ DRIFTS and by XPS. The stability of the catalyst morphology was investigated through post-reaction microscopy imaging and long-term stability tests under reaction conditions. As shown via dynamic reaction experiments, acetaldehyde and H2 were selectively produced up to 280 °C. A small drop of selectivity at higher temperatures is attributed to the formation of Ni clusters, as proven by CO-DRIFTS on the used sample. Comparison with samples of higher Ni loading, where Ni clusters are formed, clearly shows that they catalyze the undesired full decomposition of ethanol to CO, CH4, and H2.

Cu-based catalysts currently offer the most promising route to actively and selectively produce value-added chemicals via electrochemical reduction of CO2 (eCO2R); yet further improvements are required for their wide-scale deployment in carbon mitigation efforts. Here, we systematically investigate a family of dilute Cu-based alloys to explore their viability as active and selective catalysts for eCO2R through a combined theoretical–experimental approach. Using a quantum–classical modeling approach that accounts for dynamic solvation effects, we assess the stability and activity of model single-atom catalysts under eCO2R conditions. Our calculations identify that the presence of eCO2R intermediates, such as CO*, H*, and OH*, may dynamically influence the local catalyst surface composition. Additionally, we identify through binding energy descriptors of the CO*, CHO*, and OCCO* dimer intermediates that certain elements, such as group 13 elements (B, Al, and Ga), enhance the selectivity of C2+ species relative to pure Cu by facilitating CO dimerization. The theoretical work is corroborated by preliminary testing of eCO2R activity and selectivity of candidate dilute Cu-based alloy catalyst films prepared by electron beam evaporation in a zero-gap gas diffusion electrode-based reactor. Of all studied alloys, dilute CuAl was found to be the most active and selective toward C2+ products like ethylene, consistent with the theoretical predictions. We attribute the improved performance of dilute CuAl alloys to more favorable dimerization reaction energetics of bound CO species relative to that on pure Cu. In a broader context, the results presented here demonstrate the power of our simulation framework in terms of rational catalyst design.

Polyene macrolide antibiotics, which selectively bind ergosterols in fungal membranes, are important antifungal agents for the treatment of both superficial and invasive fungal infections. But severe side effects, such as nephrotoxicity, are caused by their binding to cholesterol in mammalian membranes and undermine their therapeutic values. Nevertheless, because of their excellent fungicidal efficacy, broad spectrum of activities and minimal resistance development, polyene macrolide antibiotics continue to command interest. Therefore, the pharmacological and yield improvement of polyene macrolide antibiotics becomes urgent. In past few decades, much attention was paid on the genetic and chemical modifications of polyene macrolides, and a variety of genetic engineering strategies were applied to improve the yield of polyene macrolides. Based on the literature, we summarized the structural modifications of polyene macrolides in polyene region, polyol region, exocyclic carboxyl group and sugar moiety. The heptaene nystatin analog S44HP shows considerably higher antifungal activity than that of nystatin and equal to that of amphotericin B. While the exocyclic carboxyl modifications of polyene macrolides usually led to comparable or slightly improved antifungal activity and significantly reduced hemolytic toxicity, most of alterations in polyol region resulted in decreased antifungal activity and hemolytic toxicity. Furthermore, the polyene macrolides harboring a di–sugar moiety exhibited reduced hemolytic toxicity and improved water solubility, and the modifications in C3′ amino group or C2′ hydroxyl group considerably improved the pharmacological properties. Moreover, the action mechanisms and structure–activity relationship of polyene macrolide antibiotics were elucidated, according to the data of structural modifications. It indicated that the modifications in exocyclic carboxyl group, C3′ amino group or C2′ hydroxyl group disrupt the intramolecular polar interactions and thus favor a shift to an alternate conformer that selectively binds ergosterol rather than cholesterol. In addition, the strategies for yield improvement of polyene macrolide antibiotics were summarized, including the engineering of pathway-specific and pleiotropic regulatory genes, engineering of quorum–sensing communication, and optimization of precursor supply. Although transcriptional regulation has been investigated for amphotericin, nystatin and candicidin/FR–008 biosynthesis, most detailed genetic engineering strategies for yield improvement were only carried out on pimaricin. The yield of pimaricin was improved via the overexpression of pathway- specific or pleiotropic positive regulatory genes and GBL biosynthetic genes, the disruption of pathway-specific or pleiotropic negative regulatory genes and GBL receptor encoding genes, and the addition of inducing compounds or small molecular precursors. Finally, we pointed out the challenges and problems in the structural modifications and yield improvement of polyene macrolide antibiotics, such as the possibility to obtain more modified polene analogs with exocyclic carboxyl or C3′ amino group via genetic engineering, combinational strategies for further yield improvement of polyene macrolides, and so on.

An efficient and convenient method for C5-benzylation of quinoline frameworks is developed with the using of inexpensive FeCl3 catalyst. A range of N-bisbenzylic and N-monobenzylic sulfonamides smoothly react with aliphatic amides and aromatic amides, giving the corresponding products in moderate to excellent yields.

A Cu/PPh3-catalyzed propargylic substitution reaction of diborylmethane is reported. Different substituted propargyl electrophiles can be employed in this reaction, and various synthetic valuable functional groups can be tolerated. Di-deuterated diborylmethane can also be used under these conditions and generates α-deuterated alkylboronic esters in good yield.

Dose-dependent cardiotoxicity is the leading adverse reaction seen in cancer patients treated with doxorubicin. Currently, dexrazoxane is the only approved drug that can partially protect against this toxicity in patients, however, its administration is restricted to those patients receiving a high cumulative dose of anthracyclines. Investigations into the mechanisms of cardiotoxicity and efforts to improve cardioprotective strategies have been hindered by the limited availability of a phenotypically relevant in vitro adult human cardiac model system. Here, we adapted a readily reproducible, functional 3D human multi-cell type cardiac system to emulate patient responses seen with doxorubicin and dexrazoxane. We show that administration of two NRF2 gene inducers namely the semi-synthetic triterpenoid Bardoxolone methyl, and the isothiocyanate sulfurophane, result in cardioprotection against doxorubicin toxicity comparable to dexrazoxane as evidenced by an increase in cell viability and a decrease in the production of reactive oxygen species. We further show a synergistic attenuation of cardiotoxicity when the NRF2 inducers and dexrazoxane are used in tandem. Taken together, our data indicate that the 3D spheroid is a suitable model to investigate drug induced cardiotoxicity and we reveal an essential role of the NRF2 pathway in cardioprotection providing a novel pharmacological mechanism and intervention route towards the alleviation of doxorubicin-induced toxicity.

This study investigated the impact of Nordic walking on bone properties in postmenopausal women with pre-diabetes and non-alcohol fatty liver disease (NAFLD). A total of 63 eligible women randomly participated in the Nordic walking training (AEx, n = 33), or maintained their daily lifestyle (Con, n = 30) during intervention. Bone mineral content (BMC) and density (BMD) of whole body (WB), total femur (TF), femoral neck (FN), and lumbar spine (L2-4) were assessed by dual-energy X-ray absorptiometry. Serum osteocalcin, pentosidine, receptor activator of nuclear factor kappa-B ligand (RANKL) levels were analyzed by ELISA assay. After an 8.6-month intervention, the AEx group maintained their BMCTF, BMDTF, BMCL2−4, and BMDL2−4, and increased their BMCFN (p = 0.016), while the Con group decreased their BMCTF (p = 0.008), BMDTF (p = 0.001), and BMDL2−4 (p = 0.002). However, no significant group × time interaction was observed, except for BMDL2−4 (p = 0.013). Decreased pentosidine was correlated with increased BMCWB(r = −0.352, p = 0.019). The intervention has no significant effect on osteocalcin and RANKL. Changing of bone mass was associated with changing of pentosidine, but not with osteocalcin and RANKL. Our results suggest that Nordic walking is effective in preventing bone loss among postmenopausal women with pre-diabetes and NAFLD.

The formation of urea linkages is a limitation to the application of solid amine CO2 adsorbents. Therefore, the development of solid amine adsorbents with resistance to urea linkage formation has attracted much interest over the last 5 years. In this study, we developed a facile method for synthesizing solid amine adsorbents with effective resistance to urea linkage formation. For the first time, metal nitrates were used to modify amorphous nano SiO2 to support polyethyleneimine (PEI). Three metal nitrates were investigated: aluminum, magnesium, and zinc nitrates. A series of adsorbents were prepared by controlling the mass ratios of metal nitrates and nano SiO2. After 50 cycles of adsorption–desorption tests, adsorbing at 75 °C under 15 % CO2 balanced with N2 and desorbing at 130 °C under pure CO2, Al-20%@SiO2-PEI, Al-15%@SiO2-PEI, Al-10%@SiO2-PEI, Zn-10%@SiO2-PEI, and Mg-10%@SiO2-PEI lost only 2.6 %, 4.0 %, 5.2 %, 15.9 %, and 28.8 % of their original CO2 adsorption capacities, respectively. However, SiO2-PEI, calcined SiO2-PEI, and Al-5%@SiO2-PEI lost 42.9 %, 48.6 %, and 49.6 %, respectively. By combining the infrared spectra of all the adsorbents through cyclic adsorption–desorption tests, inhibitory effects on urea linkage formation were proven for Al-20%@SiO2-PEI, Al-15%@SiO2-PEI, Zn-10%@SiO2-PEI, and Mg-10%@SiO2-PEI, and especially for Al-10%@SiO2-PEI. Through a relatively comprehensive analysis, we found that a desirable amount of metal nitrates could modify nano SiO2 samples and their corresponding adsorbents possessed a stronger H2O binding ability at 130 °C. The retained H2O could act as an inhibiting agent for the inhibition of urea linkage formation.

A stable suspension has been obtained by disbursing Mn 1.5 Co 1.5 O 4 (MCO) particles (100–300 nm in diameter) in ethanol using a ball milling process. The suspension is used for deposition of a uniform MCO coating (5–8 μm thick) on a steel (T441) substrate preheated to 200 °C by aerosol spraying. It is found that the grain size of spinel crystals in the MCO coatings ranges from 100 nm to 1 μm, and remains uniform and stable when exposed to air at 800 °C for 1000 h. However, a Cr-rich oxide scale of approximately 0.75 μm thick appears between the MCO coating and the T441 substrate during the exposure. In contrast, a bare T441 sample (without the MCO coating) is oxidized significantly more under the same exposure, forming an oxide scale of 4 μm thick. The result indicates that the spinel coating had effectively improved the oxidation resistance of T441 by inhibiting the transport of Cr. Besides, the results also suggest that aerosol spraying is a simple and cost-effective method for deposition of thin and dense protective coating.

The extremely high surface-to-volume ratio of nanoporous platinum (np-Pt) produced by dealloying was applied for tuning electrical resistance by surface charging. In the as-dealloyed state, a characteristic sign-inversion of the charging-induced resistance variation occurs, which can be associated with the electronic structure of PtO. After electrochemical reduction, the relative resistance variations of np-Pt of up to 58% could be generated by electrochemically induced adsorption and desorption, which was 1 order of magnitude larger compared with that of cluster-assembled nanocrystalline Pt. Although the maximum resistance variation was also higher than that of dealloyed nanoporous gold (np-Au), the resistance variation related to the imposed charge was reduced owing to the higher bulk resistance of Pt compared with that of Au. The sign-inversion behavior of the resistance could be recovered by re-oxidation.

Although a number of studies have been conducted on the association between plasminogen activator inhibitor-1 (PAI-1) 4G/5G polymorphism and diabetic nephropathy (DN) in Chinese population, this association remains elusive and controversial. To further assess the effects of PAI-1 4G/5G polymorphism on the risk of DN, a meta-analysis was performed in the Chinese population. Relevant studies were identified using PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure, and Chinese Biology Medicine through November, 2015. Pooled odds ratios (ORs) and 95 % confidence intervals (CIs) were used to assess the strength of the associations. This meta-analysis identified nine studies, including 777 DN cases, 413 healthy controls, and 523 DM controls. In the total analyses, a significantly elevated risk of DN was associated with variants of PAI-1 4G/5G when compared with the healthy group (4G vs. 5G, OR 2.46, 95 % CI 1.45–4.16; 4G/4G vs. 5G/5G, OR 4.32, 95 % CI 1.79–10.39; 4G/4G vs. 4G/5G +5G/5G, OR 2.96, 95 % CI 1.59–5.53; 4G/4G +4G/5G vs. 5G/5G, OR 2.78, 95 % CI 1.34–5.75) and DM group (4G vs. 5G, OR 1.93, 95 % CI 1.28–2.92; 4G/4G vs. 5G/5G, OR 2.99, 95 % CI 1.44–6.21; 4G/4G vs. 4G/5G +5G/5G, OR 2.84, 95 % CI 1.77–4.54). In the subgroup analyses stratified by ethnicity and geographic areas, it revealed the significant results in Chinese Han, in North and South China. This meta-analysis showed that the PAI-1 4G/4G variant, 4G allele might be risk alleles for DN susceptibility in the Chinese population, and further studies in other ethic groups are required for definite conclusions.

A Cu/(NHC)-catalyzed SN2'-selective substitution reaction of allylic electrophiles with gem-diborylalkanes is reported. Different substituted gem-diborylalkanes and allylic electrophiles can be employed in this reaction, and various synthetic valuable functional groups can be tolerated. The asymmetric version of this reaction was initially researched with chiral N-heterocyclic carbene (NHC) ligands.

A systematic theoretical study has been carried out on the visible light-mediated gold-catalyzed oxyarylation of alkenes. The detailed mechanism of the dual Au and photoredox-catalyzed difunctionalization, including both the photoredox and gold catalytic cycles, has been investigated. The calculation results show that the oxidative quenching of the photoredox catalyst is more favorable than reductive quenching. The favorable gold catalytic cycle is the sequence of radical addition, single electron transfer (SET), coordination, cyclization, and reductive elimination. The facility of the favorable mechanism is determined by two factors: First, both oxidation steps (i.e., radical addition and SET) occur prior to the cyclization step to generate the feasible cyclization precursor of the Au(III) complex. Second, the radical addition formally increases the electron density on the gold center and thus favors the radical addition followed by SET sequence.

The Pd-catalyzed synthesis of benzylboronic esters through coupling of aryl triflates with 1,1-diborylalkane under ambient conditions is described. Varieties of primary and secondary arylboronic esters could be successfully synthesized by this strategy. Competitive reaction demonstrated that aryl C–OTf bond was more inert than aryl bromide.

Here, we characterized a flap endonuclease 1 (FEN1) plus hairpin DNA probe (hpDNA) system, designated the HpSGN system, for both DNA and RNA editing without sequence limitation. The compact size of the HpSGN system make it an ideal candidate for in vivo delivery applications. In vitro biochemical studies showed that the HpSGN system required less nuclease to cleave ssDNA substrates than the SGN system we reported previously by a factor of ∼40. Also, we proved that the HpSGN system can efficiently cleave different RNA targets in vitro. The HpSGN system cleaved genomic DNA at an efficiency of ∼40% and ∼20% in bacterial and human cells, respectively, and knocked down specific mRNAs in human cells at a level of ∼25%. Furthermore, the HpSGN system was sensitive to the single base mismatch at the position next to the hairpin both in vitro and in vivo. Collectively, this study demonstrated the potential of developing the HpSGN system as a small, effective, and specific editing tool for manipulating both DNA and RNA without sequence limitation.

A high liquid-transportation capability is required for high-performance moisture-functional wound-dressing fabrics. However, simultaneously accelerating liquid wetting and penetration aspects remains challenging. Herein, we fabricated a fluffy polypropylene–polyethylene glycol (PP-PEG) fabric with branched micro- and nanofiber via an environmentally friendly and cost-effective melt-blowing technique. The introduction of incompatible PEG reduced the viscosity of the PP melt and decreased the dimension of fibers; thus, a branched micro- and nanofibrous structure was obtained. By incorporating the amount of 15 wt% PEG, the water content of the outer face increased from 70.3% to 270.6%. A fluffy structure in the fabric's thickness direction was achieved by tailoring the die-to-collector distance (DCD) during the melt-blowing process. The porosity increased from 87.1% to 90.1% with the DCD increased from 10 cm to 30 cm, which achieved a vertical penetration velocity of 7.02 cm/s at the water head of 90 mm. Moreover, micro- and nanofibrous morphology with the excellent mechanical properties and fine hydrolytic stability could enhance the water retention capacity that maintain the humidity of a microenvironment. This branched fluffy fabric with fast water-transportation capability is expected to be used in hygienic and medical fabric.

A polypropylene/polyester (PP/PET) composite fabric with surface roughness due to a linear valley-like structure at the micro/nano scale and broad fiber diameter distribution of 0.3–16 μm was fabricated by melt blowing with incompatible components, followed by etching of the fiber surface with sodium hydroxide. The unique valley-like structure increased the fiber surface roughness up to 0.99, resulting in a high water contact angle of 140.7°. Due to the rough morphology of the valley-like structure, the saturation adsorption capacity for soybean oil reached 20.86 g/g. Because of these outstanding properties, the PP/PET composite micro/nano-fabric with valley-like surface structure provides an alternative to high-efficiency oil sorbents.

Endothelial cells have presented a wide variety of applications including tissue engineering, artificial organs, and pharmaceutical drug screening. The new insight in exploring synthetic hydrogels which are suitable for expansion of endothelial cells and keeping their original functions will open a new era of soft and wet biomaterials as active templates for cell expansion. In this chapter, we introduce a cell culture system based on protein-free synthetic hydrogels for expansion of endothelial cells. The negatively charged synthetic hydrogels, such as PNaAMPS and PNaSS, can promote endothelial cell proliferation to form a monolayer, without surface modification of any cell-adhesive proteins or peptides, under the environment of serum-containing medium. Moreover, the synthetic hydrogels can maintain the original functions of the expanded cells. In the sections of the effect of chemical structure and zeta potential on cell behaviors, we introduce the effect of physicochemical properties of fully synthetic hydrogels, i.e., chemical structure, charge density, and surface topography, on static cell behaviors (adhesion, spreading, morphology, proliferation, cytoskeletal structure, and focal adhesion) and dynamic cell behaviors (migration velocity, morphology oscillation). In addition, the effect of hydrogel properties on cell behaviors is correlated well with the adsorption of protein derived from cell culture medium. In the section of application of protein-free hydrogels in biomedical field, the platelet compatibility and surface friction of endothelial cell monolayers cultured on hydrogel templates, selective cell adhesion and proliferation on micro-patterned hydrogel surfaces, as well as proliferation of endothelial cells on tough hydrogels are introduced.

Autophagy is a regulated process that sequesters and transports cytoplasmic materials such as protein aggregates via autophagosomes to lysosomes for degradation. Dapper1 (Dpr1), an interacting protein of Dishevelled (Dvl), antagonizes Wnt signaling by promoting Dishevelled degradation via lysosomes. However, the mechanism is unclear. Here, we show that Dpr1 promotes the von Hippel-Lindau tumor suppressor (VHL)-mediated ubiquitination of Dvl2 and its autophagic degradation. Knockdown of Dpr1 decreases the interaction between Dvl2 and pVHL, resulting in reduced ubiquitination of Dvl2. Dpr1-mediated autophagic degradation of Dvl2 depends on Dvl2 aggregation. Moreover, the aggregate-prone proteins Dvl2, p62, and the huntingtin mutant Htt103Q promote autophagy in a Dpr1-dependent manner. These protein aggregates enhance the Beclin1-Vps34 interaction and Atg14L puncta formation, indicating that aggregated proteins stimulate autophagy initiation. Ubiquitination is not essential for the aggregate-induced autophagy initiation as inhibition of the ubiquitin-activation E1 enzyme activity did not block the aggregate-induced Atg14L puncta formation. Our findings suggest that Dpr1 promotes the ubiquitination of Dvl2 by pVHL and mediates the protein aggregate-elicited autophagy initiation.