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Hydrogenation of CO2 using renewable hydrogen to build block chemicals, such as lower olefins and aromatics, not only mitigates the CO2 emissions, but also realizes the utilization of CO2 as a carbon resource. However, it is difficult to activate the inert CO2 and precisely control the C–C coupling. As a result, the hydrogenation of CO2 mainly produces C1 product, and selective synthesis of hydrocarbon chemicals with C–C chains is challenging. In 2016, Chinese scientists first reported the relay catalysis, in which metal oxides and acidic zeolites were integrated together as bifunctional catalysts, for converting synthesis gas to lower olefins and aromatics. Inspired by this, a number of bifunctional catalysts have been recently reported for the hydrogenation of CO2 to lower olefins and aromatics, using the concept of replay catalysis. In this review, we summarize the recent advances in the transformation of CO2 to high-value chemicals and try to clarify how to connect two reactions with different characteristics. The key factors that affect the product distribution are also discussed.

In this work, a series of Cu(II)-doped Bi2WO6 nanomaterials with good photo-response properties were facile synthesized and used to obtain efficient peroxymonosulfate (PMS) activation activity for norfloxacin (NOF) removal under visible LED light irradiation. It was found that Cu–Bi2WO6 presents superior catalytic performance for NOF degradation in comparison with pristine Bi2WO6, attributed to the partial substitution of Bi3+ by Cu ions. Moreover, the effects of experimental conditions were carefully investigated, including PMS concentration, catalyst dosage and initial pH, and the experimental data fitted well with the pseudo-first-order model. Experimental results implied that there was a synergic effect of visible LED light energy and the sulfate radical (SR)-Fenton reaction. Additionally, the 5Cu–Bi2WO6 nanomaterial presented the best degradation efficiency of 89.27% and exhibited high NOF degradation in 5 cycles with limited Cu leaching. Furthermore, EPR and radical quenching experiments were performed to identify the reactive oxygen species presented in the SR-photo-Fenton reaction. Finally, the major degradation intermediates of NOF were detected, and a possible degradation pathway was given. Thus, a mechanism of the significant photocatalytic activity enhancement by copper doping of the Bi2WO6 catalyst was proposed.

Weathering is a key process in the transfer of material from continents to the hydrosphere. A latosol profile in Zhanjiang, Guangdong Province, South China, formed through intense weathering of basalt, was studied to improve understanding of Ba isotopic fractionation during basalt weathering. Profile horizons were grouped into Ba-depleted and Ba-enriched layers (D- and E-layers, respectively) according to the mass fraction of Ba lost or gained from the weathered profile relative to bedrock. δ137/134Ba values in the soil profile ranged from −0.22‰ to +0.02‰, lower than those of the parent basaltic rock (0.03‰ ± 0.03‰). In the D-layers, Ba isotopic fractionation can be explained by Rayleigh fractionation, implying that heavy Ba isotopes are preferentially leached. The Rayleigh fractionation model is not applicable to the E-layers because they preferentially acquired isotopically light Ba isotopes during weathering. Results indicate a net loss of heavy Ba isotopes during strong weathering of basalt due to the precipitation of Fe Mn (oxyhydr)oxides and adsorption on secondary minerals. A mass-balance model indicates that the average δ137/134Ba value of materials leached from the weathered profile is ~0.08‰, slightly higher than that of the bedrock. This suggests a loss of heavy Ba isotopes into the hydrosphere during weathering of basalt, consistent with the enrichment of heavy Ba isotopes in river waters.

The Sumdo eclogite, located in the central Lhasa Terrane, Tibet, has received much attention as it has important implications for the tectonic evolution of the Tibet orogenic belt. Aiming to constrain the Lithium (Li) isotope characteristics of rocks in subduction zones, we investigated whole-rock major and trace elements, Li isotopes as well as oxygen (O) and radiogenic (Sr, Nd, and Pb) isotopes on 20 Sumdo eclogite samples. The investigated samples display REE patterns similar to N-MORB, with relatively homogeneous bulk eNd(t=260Ma) values ranging from +4.0 to +7.8. These data suggest that protoliths of the Sumdo eclogite were N-MORB-type oceanic basalts. Yet, initial 87Sr/86Sr and δ18O are heterogeneous and range from 0.703703 to 0.706645 and from +4.9 to +8.9‰, respectively. A positive correlation between Sr and oxygen isotopic compositions suggests that the MORB protoliths had experienced low temperature seafloor alteration prior to subduction. The Li contents and δ7Li values of Sumdo eclogite vary from 3.64 to 29.7 µg/g and −1.1 to +4.0‰, respectively, significantly lower than those of low T altered MORBs (AOC) that usually have high Li contents (up to 33 µg/g) and heavy Li isotopic compositions (δ7Li up to +14‰). Modelling results suggests limited Li isotopic fractionation during dehydration. After eliminating the effect of diffusion, we suggest that a rehydration stage during exhumation may be responsible for the Li isotope systematics of the Sumdo eclogite. The fluids (

Recently, to improve the anti-fouling flashover performance of porcelain and glass insulators, room temperature vulcanized (RTV) silicone rubber coatings have been widely applied to their surface. However, it was found that, in warm and humid areas in China, the presence of RTV silicone coating could facilitate the growth of biological contamination such as algae. This study firstly analyzed the biofouling regularity of algae growth on the surface of outdoor RTV-coated insulators, considering growth direction, distribution on sheds, substation equipment, insulating material and effect of corona discharge. The effects of algae on the surface micro morphology, functional groups and flashover voltage of field insulator were then studied. The effects of environmental factors on algae growth were studied in detail. Finally, the influence of algae on the hydrophobicity and flashover characteristics of the RTV coating was examined. Through research, the growth regularity of algae on insulator surface is presented and put forward some measures to prevent and control algae growth. The results also showed that the presence of algae could decrease flashover performance of the RTV-coated insulators. However, the effect of algae on the aging of materials was insignificant.

Genetic transformation through somatic embryogenesis is a major tool for improving cotton’s (Gossypium hirsutum L.) development and defenses. However, the low efficiency of somatic embryogenesis seriously limits cotton’s biotechnology-based breeding and gene functional analyses. In this study, the effects of different light qualities on callus morphology and embryogenic callus induction in cotton were evaluated. Embryogenic callus formation was affected by different light regimes during the induction and expression phases. Red light treatments during the induction phase significantly promoted the formation of embryogenic calli, reaching 94.0%, and the differentiation period was reduced to 30 days compared with more than 60 days under white light conditions. Calli were of a moderate size and had moderate peroxidase, superoxidase dismutase, and catalase activity levels under red light conditions, which may maintain the balance between callus growth and differentiation. The highest total polyamine, spermidine, and spermine contents, and the lowest putrescine content, were detected during red light treatments. Additionally, endogenous auxin levels were significantly greater in red light-treated calli, and the expression levels of the somatic embryogenesis marker genes AGAMOUS-like 15, LEAFY COTYLEDON1, LEAFY COTYLEDON2, BABY BOOM, and WUSCHEL were up-regulated under red light compared with white light conditions. Thus, red light applied in the induction phase favored embryogenic callus differentiation, possibly through physiological responses to light quality. A high-efficiency cotton somatic embryogenesis protocol using red light applications will help clarify the mechanism of somatic embryogenesis.

Organometal halide perovskite solar cells are regarded as a remarkable progress in the field of photovoltaic technology. However, the poor stability of perovskite solar cells becomes a serious issue restricting the commercial applications. Here, we investigate the doping of cesium cations in methylammonium lead iodide perovskite solar cells and the effect on the device stability. Homogeneous doping of cesium into methylammonium lead iodide has been obtained with a concentration up to 15%. For the doped solar cells, an efficiency of 13.2–16.5% has been achieved without significant loss compared with the undoped cells. More importantly, the device stability has been dramatically improved by cesium doping. After staying in a dark atmospheric environment for 7 and 30 days, the unencapsulated devices with 20% cesium doping retained 83% and 60% of the initial efficiency, while the undoped cells remained only 59% and 25% of the initial efficiency, respectively. Density functional theory calculations suggest that the cesium dopants are more positively charged than the methylammonium cations. Meanwhile, the doping of cesium increases the averaged charge of iodines. As a result, the Coulomb interactions between the methylammonium cations and the framework of [PbI6] octahedrons are strengthened, which is considered as an efficient factor to prohibit the diffusion of methylammonium cations and therefore stabilize the perovskite structure.

Metal oxide-zeolite bifunctional catalysts allow coupling of reactions and so enhance catalytic processes, but structure and reactivity control is difficult. Here, a general synthesis is presented for metal oxide-zeolite double-shelled hollow spheres, which outperform other catalysts for petroleum production. Metal-zeolite composites with metal (oxide) and acid sites are promising catalysts for integrating multiple reactions in tandem to produce a wide variety of wanted products without separating or purifying the intermediates. However, the conventional design of such materials often leads to uncontrolled and non-ideal spatial distributions of the metal inside/on the zeolites, limiting their catalytic performance. Here we demonstrate a simple strategy for synthesizing double-shelled, contiguous metal oxide@zeolite hollow spheres (denoted as MO@ZEO DSHSs) with controllable structural parameters and chemical compositions. This involves the self-assembly of zeolite nanocrystals onto the surface of metal ion-containing carbon spheres followed by calcination and zeolite growth steps. The step-by-step formation mechanism of the material is revealed using mainly in situ Raman spectroscopy and X-ray diffraction and ex situ electron microscopy. We demonstrate that it is due to this structure that an Fe2O3@H-ZSM-5 DSHSs-showcase catalyst exhibits superior performance compared with various conventionally structured Fe2O3-H-ZSM-5 catalysts in gasoline production by the Fischer-Tropsch synthesis. This work is expected to advance the rational synthesis and research of hierarchically hollow, core-shell, multifunctional catalyst materials.

Thermal responses and fatigue behaviors of the tungsten armor of monoblock divertor under steady-state and transient high heat flux (HHF) loads as well as the coupling of the two were simulated and analyzed by the finite element method. It was found that, under the action of thermal cycle loads, the earliest fatigue failure area of tungsten armor is on the surface, and with the increasing of HHF load, the damage area of the armor extends also, while the transient load only causes damage on surface of the armor. The fatigue lifetime of tungsten armor decreases rapidly with the increase of load, whether under steady-state load or transient load. Different transient load under the same steady-state load is researched. When two loads are coupled, the fatigue life is shorter as the load value is high, while the fatigue lifetime is basically unchanged when the transient load is the same under different steady-state loads, that is to say, the steady-state load has little influence on the results, and the transient load during ELMs is the leading factor for the fatigue lifetime.

Long-term excessive alcohol intake can easily lead to gastritis, gastric ulcer, and gastric bleeding. In this paper, the gastric acid-responsive hydrogel of CS-NAC/alginate/tilapia collagen peptide (CS-NAC/ALG/TCP) was developed. Its structure and properties were determined. The alcohol-induced gastric mucosal injury models in mice were established to evaluate the protective effects of CS-NAC/ALG/TCP. The results showed that CS-NAC/ALG/TCP was successfully fabricated, and it showed a sustained release of TCP, strong mucoadhesion, and excellent biodegradability in vitro. In the animal experiments, CS-NAC/ALG/TCP improved the oxidative stress status of the gastric mucosa by increasing the levels of SOD, GSH, and CAT in tissues. It also down-regulated the expression of MPO, TNF-α, IL-1β, and IL-6, and increased the production of gastric protective factors such as PGE2 and NO in mouse stomach, thereby reducing the alcohol-induced inflammation and protecting the gastric mucosal injury. Besides, CS-NAC/ALG/TCP can also increase the activities of alcohol metabolism enzymes to improve alcohol metabolism, thereby reducing alcoholic damage. In conclusion, CS-NAC/ALG/TCP is a promising candidate for the treatment of alcohol-induced gastric injury.

In plants, light is an important environmental signal that induces meristem development and interacts with endogenous signals, including hormones. We found that treatment with 24 h of low-fluence red light (24 h R) or 24 h of darkness (24 h D) following root excision greatly increased the frequency of shoot generation, while continuous low-fluence red light in callus and shoot induction stages blocked the explants&rsquo, ability to generate shoots. Shoot generation ability was closely associated with WUS expression and distribution pattern. 1-N-naphthylphtalamic acid (NPA) disrupted the dynamic distribution of the WUS signal induced by early 24 h R treatment, and NPA plus 24 R treatment increased the average shoot number compared with early 24 h R alone. Transcriptome analysis revealed that differentially expressed genes involved in meristem development and hormone signal pathways were significantly enriched during 24 R or 24 D induced shoot regeneration, where early 24 h R or 24 h D treatment upregulated expression of WOX5, LBD16, LBD18 and PLT3 to promote callus initiation and formation of root primordia, and also activated WUS, STM, CUC1 and CUC2 expression, leading to initiation of the shoot apical meristem (SAM). This finding demonstrates that early exposure of explants to transient low-fluence red light or darkness modulates the expression of marker genes related with callus development and shoot regeneration, and dynamic distribution of WUS, leading to an increased ability to generate shoots.

To investigate the behaviour of Ba isotopes during carbonatite petrogenesis and to explore the possibility of using carbonatites to constrain the Ba isotopic composition of the mantle, we report high-precision Ba isotopic analyses of: (1) carbonatites and associated silicate rocks from the only active carbonatite volcano, Oldoinyo Lengai, Tanzania, and (2) Archean to Cenozoic carbonatites from Canada, East Africa, Germany and Greenland. Carbonatites and associated phonolites and nephelinites from Oldoinyo Lengai have similar δ137/134Ba values that range from +0.01 to +0.03‰, indicating that Ba isotope fractionation during carbonatite petrogenesis is negligible. The limited variation in δ137/134Ba values from −0.03 to +0.09‰ for most carbonatite samples suggests that their mantle sources have a relatively homogeneous Ba isotopic composition. Based on the carbonatites investigated in this work, the average δ137/134Ba value of their mantle sources is estimated to be +0.04 ± 0.06‰ (2SD, n = 16), which is similar to the average value of +0.05 ± 0.06‰ for mid-ocean ridge basalts. The lower δ137/134Ba value of −0.08‰ in a Canadian sample and higher δ137/134Ba values of +0.14‰ and + 0.23‰ in two Greenland samples suggest local mantle isotopic heterogeneity that may reflect the incorporation of recycled crustal materials in their sources.

LncRNA PCGEM1 (PCGEM1) has been reported to exert essential effects on the development and progress of various tumors, while the detailed effects and possible mechanisms of PCGEM1 in cervical carcinoma remain unknown. In the present study, PCGEM1 was over-expressed in cervical carcinoma cells as evidenced by real-time quantitative polymerase chain reaction (RT-qPCR) assay. Knockdown of PCGEM1 significantly repressed proliferation, migration, and invasion, while induced G1 arrest in cervical carcinoma cells. In addition, PCGEM1 was predicted to target miR-642a-5p by bioinformatics software, which was further confirmed by luciferase reporter assay. Besides, RT-qPCR assay indicated that miR-642a-5p expression was decreased in cervical carcinoma cells and knockdown of PCGEM1 could accelerate miR-642a-5p expression. Moreover, inhibition of miR-642a-5p partly abolished the functions of PCGEM1 knockdown on proliferation, cell cycle, migration and invasion of cervical carcinoma cells. Furthermore, miR-642a-5p could bind to the 3'-UTR of LGMN, which was over-expressed in the cervical carcinoma cells. Suppression of LGMN partly restored the functions of miR-642a-5p inhibitor on proliferation, cell cycle distribution, migration and invasion in the cervical carcinoma cells treated with the PCGEM1 shRNA. Taken together, our data indicated that knockdown of PCGEM1 inhibited proliferation, migration and invasion in cervical carcinoma by modulating the miR-642a-5p/ LGMN axis.

Fluids released from subducting slabs play an important role in mantle metasomatism and arc magmatism. Magnesium could be mobile in subduction-zone fluids and Mg isotopic signatures of melange rocks may provide information on crust-mantle interactions at subduction zones. To investigate the behaviour of Mg isotopes during fluid metasomatism along the slab-mantle interface, we report Mg isotopic compositions of a set of well-characterized samples from the ultramafic blocks in the Franciscan Complex of California. The partially serpentinized and completely serpentinized peridotites have δ26Mg values (from −0.26 to −0.14) clustered around the mantle value, indicating small Mg isotope fractionation during peridotite serpentinization. Samples with serpentine completely replaced by talc have lower MgO contents and heavier Mg isotopic compositions (δ26Mg of −0.13 to −0.01) than serpentinized peridotites, implying that Mg was non-conservative during this metasomatic replacement. The shift toward higher δ26Mg values of talc-dominated metaperidotites reflects the preferential loss of light Mg isotopes into fluids via Rayleigh distillation during the dehydration reactions that produced talc from serpentine. On the other hand, samples with talc completely replaced by tremolite have lighter Mg isotopic compositions (δ26Mg of −0.50 to −0.41) and higher CaO contents than the talc-dominated samples. These features suggest a metasomatic process involving isotopically light carbonate-rich fluids derived from the subducting slab. Collectively, large Mg isotope fractionation occurs during multistage fluid-rock interactions within the Franciscan subduction channel, which provides direct evidence for significant Mg isotopic variation during fluid metasomatism along the slab-mantle interface. This may account for the observed heterogeneous Mg isotopic compositions of arc lavas. Magnesium isotopes thus could be a potentially useful tracer of crust-mantle interactions at subduction zones.

The upper continental crust (UCC) is an important reservoir of Ba within the Earth. We report high precision (≤±0.05‰, 2SD) Ba isotopic data for 71 samples (including granites, granodiorites, loess, glacial diamictites, and river sediments) to constrain the Ba isotopic composition of the UCC. I-type granites from the Fogang batholith, Southeastern (SE) China, exhibit variable δ137/134Ba (−0.16‰ to 0.01‰), which may be due to isotopic fractionation during the latest stages of magmatic differentiation. The δ137/134Ba of S-type granites from Darongshan-Shiwandashan, SE China (−0.03‰ to 0.11‰) correlate with ɛNd (t), likely reflecting mixing of heterogeneous crustal source materials. Five A-type granites with high SiO2 contents (∼76 wt%) from Nankunshan, SE China have remarkably low δ137/134Ba (−0.47‰ to −0.33‰), which possibly arose from magmatic differentiation or assimilation of crustal materials with light Ba isotopic compositions. Loess from northwestern China has homogeneous δ137/134Ba (−0.02‰ to 0.03‰) that shows no correlation with bulk compositions, sample locations, or degree of chemical weathering, suggesting that loess is representative of the average Ba isotopic composition of the UCC. Three river sediments from northern China have δ137/134Ba similar to that of loess. The δ137/134Ba of glacial diamictites vary with CIA values: those with high CIA (≥60) have heterogeneous δ137/134Ba (−0.19‰ to 0.35‰), while those with low CIA ( √ n , n = 71), which is similar to the average Ba isotopic composition of the upper mantle, but significantly lower than δ137/134Ba of seawater.

The influence of the Ti alloy substrate (α, β, α + β) on the anodic oxidation process was studied. The surface morphology, composition and crystalline structure were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). It was shown that the surface morphology and crystalline structure of anodic oxide films were considerably affected by the Ti alloy substrate. The surface morphologies of the oxide films retain their matrix microstructure characteristics. The oxide film on the residual β phase contains a trace amount of V, Zr, Mo element for TA15. Compared to the secondary α phase, the β phase has a higher degree of oxidation for TB6. The oxide film has the higher Al content on the secondary α phase, while the oxide film formed on β-phase has the higher V content. The XPS results show that the Al, Mo, V, Zr alloy elements of TA15 are involved in anodic oxidation and exist as Al2O3, MoO3, V2O5, ZrO2. Likewise, the Al, V alloy elements of TB6 are involved in anodic oxidation and exist as Al2O3, V2O5, but Fe element is not involved in anodic oxidation. The anodic oxide films are partly crystallized and mainly amorphous for the three kinds of titanium alloys. The TA15 anodic oxide film has the highest crystal content, and TB6 has the least.

Lowering the oxygen content in biofuels is of vital importance, since high oxygen level content leads to low stability, low heat value, and corruption in engines. Here we report on the thermally activated decarboxylation of fatty acids, raw materials for biofuel production, on an anisotropic Au(110) surface. Due to the one-dimensional (1D) geometrical constraint of the surface reconstruction, linear fatty acid molecules (C30H60O2) are decarboxylated and polymerized at their terminal ends at mild temperatures, resulting in the formation of oxygen-free aliphatic hydrocarbons. Different reaction stages of the decarboxylation were monitored by high-resolution scanning tunneling microscopy and X-ray photoemission spectroscopy. On the basis of density functional theory calculations, a two-step process was proposed for the fatty acid decarboxylation. Our work demonstrates a novel strategy for deoxygenation of fatty acids on a 1D constrained surface as a model catalytic system for producing low oxygen content bio...

s CuO-ZnO/SiO2 catalysts with various Zn/Cu molar ratios were prepared by precipitation and characterized by XRD, H2-TPR, TEM, XAES and catalytic performance for hydrogenation of dimethyl oxalate. Characterizations revealed that suitable zinc incorporation resulted in higher Cu+ content on the surface of catalysts, better dispersion of Cu0 particles and better sintering resistance. Cu0.8Zn0.2/SiO2 exhibited the best activity and sintering resistance with 99.5% DMO conversion and 91.5%selectivity to ethylene glycol, after deactivation treatment (T = 400 °C, H2 atmosphere, 2.0 h), the catalyst maintained its activity with DMO conversion of 99.0%, while selectivity to ethylene glycol increased to 95.2%.

Cu(OH)2 nanowires were prepared and incorporated into poly(vinylidene fluoride) (PVDF) to fabricate Cu(OH)2-PVDF ultrafiltration (UF) membrane via immersion precipitation phase inversion process. The effect of Cu(OH)2 nanowires on the morphology of membranes was investigated by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) measurements. The results showed that all the Cu(OH)2-PVDF membranes had wider fingerlike pore structure and better hydrophilicity, smoother surface than pristine PVDF membrane due to the incorporation of Cu(OH)2 nanowires. In addition, water flux and bovine serum albumin (BSA) rejection were also measured to investigate the filtration performance of membranes. The results indicated that all the Cu(OH)2-PVDF membranes had high water flux, outstanding BSA rejection and excellent antifouling properties. It is worth mentioning that the optimized performance could be obtained when the Cu(OH)2 nanowires content reached 1.2 wt%. Furthermore, the membrane with 1.2 wt% Cu(OH)2 nanowires showed outstanding oil-water emulsion separation capability.

N-butanol, as a biofuel, could be one kind of engine fuel to relieve energy crisis and reduce particle emission. In this paper, n-butanol was applied to a spark-ignition engine equipped with dual-injection system. Three different fuel injection approaches were tried, including direct injection of gasoline and n-butanol with different volume mixing ratio (GNDI), n-butanol intake port injection combined with gasoline direct injection (N-GxDI) and gasoline intake port injection combined with n-butanol direct injection (G-NxDI), and finally the best method was recommended based on combustion and particle emission characteristics. Experiments were conducted under stoichiometric and rich mixture (excess air coefficient was at 0.9) condition to obviously present particle emission characteristics, including particle number (PN), particle matter (PM) and particle distribution. The results indicated that with the rising of n-butanol blending volume ratio (NBr) for GDNI, indicated mean effective pressure (IMEP) increased firstly and decreased afterward, total particle matter (TPM) decreased constantly, however, total particle number (TPN) and nucleation mode particle number (NPN) dropt first and then rose, accumulation mode particle number (APN) increased continuously. 20% was regarded as the best NBr, because it had the highest IMEP, TPN could be decreased by 8.63%, and TPM could be decreased by 30.88% compared with GDI under stoichiometric condition; With the increasing of fuel (gasoline or n-butanol) direct injection ratio (DIr) for G-NxDI and N-GxDI, IMEP decreased constantly, TPM increased continually, however, TPN and NPN both decreased firstly and increased afterward, APN increased endlessly. There was also one best DIr to achieve the lowest TPN; Comparing three injection approaches, N-GxDI with 40% DIr was the best, because it owned the lowest TPN which was decreased by 51.07% and TPM could almost be ignored compared with GDI under stoichiometric condition. However, this approach had to sacrifice 1% decrease of IMEP compared with pure gasoline intake port injection, while the value was still above GDI.

An investigation on the removal of aluminum ions from phosphoric acid by ion exchange resin (001X7)732 was carried out for optimizing the wet process of phosphoric acid (WPA). Various parameters such as contact time, temperature, ratio between resin and solution, and agitation speed were studied to evaluate their effects on the ion exchange equilibrium and optimizing the process conditions. The experimental conditions of temperature 40 °C, contact time 20 min, ratio between resin and solution 50 g/200 g, and agitation speed 500 rpm could get the best sorption capacity at 6.62 × 10−3 g/g and removal efficiency at 49.8 %. Empirical kinetic equations such as pseudo-first-order and pseudo-second-order kinetic equations, and broadly applicable diffusion models such as film diffusion, pore diffusion, and moving boundary process were employed to process the dates. Results showed the ion exchange process followed the pseudo-second-order model. In addition, the rate limiting steps in the ion exchange reaction were both of film and particle diffusion. The activation energy (10.77 KJ/mol) also indicated a diffusion controlled process. Furthermore scanning electron microscopy (SEM) coupled with X-ray energy dispersed spectrometer and FTIR analyses for the resin before and after aluminum adsorption, demonstrated that aluminum containing nodules existed in the interior of the resin, the functional group is –SO3–. This article is protected by copyright. All rights reserved

De novo root regeneration in stem cutting is essential for massive propagation of Platycladus orientalis (L.) Franco, which is one of the major ecological and economic tree species in China. However, the details of adventitious root (AR) formation and how it is controlled by inherent hormones are still ambiguous. In this study, histological analysis, immunohistochemical localization combined with quantitative hormonal analysis were conducted to investigate how cutting induces the AR formation of P. orientalis. It was explicitly seen that AR emerged from either calli- or non-calli- covered barks. The anatomical structure showed that cutting initiated the inducible formation of AR primordia in multiple sites, including xylem, phloem, medullary ray, and annulus randomly. The tissue-specific accumulations of indole-3-acetic acid (IAA) surged in cambia-derived calli, basal boundaries of AR primordia, and AR, supporting the idea that the mode action of auxin was key to diverse types of root organogenesis. Meanwhile, the data showed that similar to that of IAA, the contents of abscisic acid (ABA) and zeatin (ZT) peaked at early stages of AR formation and deceased gradually in both phloem and xylem across the later stages, suggesting their indispensable roles in AR initiation. On contrary, jasmonic acid (JA) roughly maintained at extremely high levels in phloem comparing with the xylem tissues thoroughly, indicating its presence was involved in phloem-specific reorganization during AR formation. Collectively, the results provide a time-course histological dissection of AR formation, revealing developmental homeostasis of four main endogenous hormones, and providing theoretically a potential way to improve performance of stem-cutting in P. orientalis through regulating hormone actions in the future.

The catalytic performance of composite catalysts is not only affected by the physicochemical properties of each component, but also the proximity and interaction between them. Herein, we employ four representative oxides (In 2 O 3 , ZnO, Cr 2 O 3 , and ZrO 2 ) to combine with H-ZSM-5 for the hydrogenation of CO 2 to hydrocarbons directed by methanol intermediate and clarify the correlation between metal migration and the catalytic performance. The migration of metals to zeolite driven by the harsh reaction conditions can be visualized by electron microscopy, meanwhile, the change of zeolite acidity is also carefully characterized. The protonic sites of H-ZSM-5 are neutralized by mobile indium and zinc species via a solid ion-exchange mechanism, resulting in a drastic decrease of C 2+ hydrocarbon products over In 2 O 3 /H-ZSM-5 and ZnO/H-ZSM-5. While, the thermomigration ability of chromium and zirconium species is not significant, endowing Cr 2 O 3 /H-ZSM-5 and ZrO 2 /H-ZSM-5 catalysts with high selectivity of C 2+ hydrocarbons. This work preliminarily unveils the overlooked element migration and its profound impact on the catalytic behaviors of bifunctional catalysts for CO/CO 2 hydrogenation, providing insights into the rational design of emerging multifunctional catalysts.

A novel magnetic nano-sorbent Fe3O4/Ag was synthesized and applied to capture the elemental mercury from the simulated flue gas. The morphology, components and crystal phase of the sorbents were characterized by transmission electron microscope (TEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD), respectively. The mercury removal performance of the sorbents was investigated through the fixed-bed tests. The results indicated that silver was successfully loaded on the surface of Fe3O4 particles, which could significantly enhance the Hg0 removal performance of the sorbents. Flue gas components, including CO2, SO2, and NO, have little impact on the Hg0 removal performance of Fe3O4/Ag sorbents, while O2 has a slightly positive effect. The Hg0 removal efficiency decreased with the increasing of temperature, Hg0 inlet concentration and gas hourly space velocity. Only one broad mercury desorption peak at approximately 210 °C could be observed during the temperature-programmed desorption (TPD) process, which indicated that mercury species existing on the surface of Fe3O4/Ag sorbents might be elemental mercury instead of oxidized mercury. Furthermore, the reusability tests showed that the Fe3O4/Ag sorbents could be efficiently regenerated and reused. Finally, the theoretical analysis based on the DFT method showed that a weak chemisorption of Hg0 on Fe3O4 sorbents changed to a strong chemisorption when silver was loaded. The results of theoretical analysis conformed to the experiments results well.

Firmness of skin is an important quality of processing cucumbers, which is a feature of the palisade epidermis in these types compared to flat epidermis in fresh cucumbers. This study was conducted to map the Pe (palisade epidermis) and analyse the candidate gene. Populations derived from the cross of two inbred lines, NCG122 with fruit flat epidermis and NCG121 with fruit palisade epidermis, were used to identify the inheritance of palisade epidermis and to map the gene involved in its development. The results showed that the palisade epidermis trait is controlled by a single gene, Pe, that is dominant over flat epidermis. Seven simple sequence repeat (SSR) and five insertion deletion (Indel) markers were identified to be linked to the Pe gene. It was mapped to cucumber chromosome 5 (Chr.5) between SSR14611 and Indelpe12 with genetic distances of 0.3 cM and 0.2 cM, respectively. The physical distance of the genomic region harbouring the gene was 227.5 kb with 26 predicted candidate genes. The accuracy of marker-assisted selection using the molecular markers, Indelpe12 and SSR14611, was 68% and 88%, respectively.

Arctiin is the most abundant bioactive compound contained in the Arctium lappa plant. In our previous study, we isolated one single bacterium capable of bioconverting arctigenin, an aglycone of arctiin, to 3′-desmethylarctigenin (3′-DMAG) solely. However, to date, a specific bacterium capable of producing other arctiin metabolites has not been reported. In this study, we isolated one single bacterium, which we named Eggerthella sp. AUH-JLD49s, capable of bioconverting 3′-DMAG under anaerobic conditions. The metabolite of 3′-DMAG by strain AUH-JLD49s was identified as 3′-desmethyl-4′-dehydroxyarctigenin (DMDH-AG) based on electrospray ionization mass spectrometry (ESI–MS) and 1H and 13C nuclear magnetic resonance spectroscopy. The bioconversion kinetics and bioconversion capacity of strain AUH-JLD49s were investigated. In addition, the metabolite DMDH-AG showed an inhibitory effect on cell growth of human colon cancer cell line HCT116 and human breast cancer cell line MDA-MB-231.

A majority of perovskite solar cells use indium–tin oxide (ITO) or fluorine-doped tin oxide (FTO) as the transparent electrodes. As a promising transparent electrode material, aluminum-doped zinc oxide (AZO) possesses comparable transmittance and conductivity and is environment-friendly and low-cost. Herein, we report the fabrication of perovskite solar cells using AZO as the transparent electrodes. A fullerene derivative layer was used to adjust the energy level alignment and to promote electron transport between the CH3NH3PbI3–xClx absorption layer and the AZO electrode. Power conversion efficiency of 13.07% and open-circuit voltage of 1.02 V have been achieved. Our work demonstrates the potential of fabricating cost-effective solar cells on AZO with mild processing temperatures.

An engine experimental platform with gasoline port injection and hydrogen/gasoline direct injection was built to study the effects of combined injection mode and ignition timing on combustion and emission characteristics of a spark-ignition engine. The study was performed in three modes, including gasoline port injection (GPI) mode, gasoline port injection plus gasoline direct injection (GPI + GDI) mode, and gasoline port injection plus hydrogen direct injection (GPI + HDI) mode, under the conditions of a constant excess air ratio and speed. Through the comparison and analysis of the three modes, the results reveal that combined injection is beneficial to increasing brake power and decreasing brake-specific fuel consumption and hydrocarbon (HC) and carbon monoxide (CO) emissions. The combustion process will be accelerated and concentrated with combined injection as well as hydrogen addition, and the effect of adding hydrogen is stronger than that of gasoline direct injection. Brake thermal efficiency and ...

The effects of a rolling process and heat treatment on the mechanical and thermal properties of an Al-Si-Fe alloy were studied. The achieved thermal conductivity of the as-rolled alloy treated by a T6 heat treatment was 188.22 W/(m&middot, K), which is as good as that of the as-cast alloy treated by the T6 heat treatment directly, mostly because of changes in the silicon morphology. The results also revealed that the lower quantity of precipitated Al8Fe2Si and Mg2Si phases had no obvious effect on the thermal properties of the material because the interphase spaces between precipitated phases were larger than the mean free path of electrons. However, the precipitated second phases influenced the elongation. The best mechanical properties of the Al-Si-Fe alloy were obtained by rolling and T6 treatment. The corresponding best tensile strength, yield strength, and elongation were 244 MPa, 295 MPa, and 9.56%, respectively, which are attributed to the near-spherical shape, small size, homogeneous distribution of the Si particles, and the precipitation strengthening of Mg2Si.

New protecting group chemistry is used to greatly simplify imaging probe production. Temperature and organic solvent-sensitive biomolecules are covalently attached to a biotin-bearing dioxaborolane, which facilitates antibody immobilization on a streptavidin-agarose solid-phase support. Treatment with aqueous fluoride triggers fluoride-labeled antibody release from the solid phase, separated from unlabeled antibody, and creates [(18)F]-trifluoroborate-antibody for positron emission tomography and near-infrared fluorescent (PET/NIRF) multimodality imaging. This dioxaborolane-fluoride reaction is bioorthogonal, does not inhibit antigen binding, and increases [(18)F]-specific activity relative to solution-based radiosyntheses. Two applications are investigated: an anti-epithelial cell adhesion molecule (EpCAM) monoclonal antibody (mAb) that labels prostate tumors and Cetuximab, an anti-epidermal growth factor receptor (EGFR) mAb (FDA approved) that labels lung adenocarcinoma tumors. Colocalized, tumor-specific NIRF and PET imaging confirm utility of the new technology. The described chemistry should allow labeling of many commercial systems, diabodies, nanoparticles, and small molecules for dual modality imaging of many diseases.

Porous TiO2 ceramic coatings with high contents of Si and P were fabricated on a Ti6Al4V alloy using hybrid processing of laser surface melting (LSM) and microarc oxidation (MAO). The effect of LSM pretreatment on the growth behavior and mechanical properties of the MAO coating was studied. The results showed that the MAO coating on LSM pretreatment Ti6Al4V (LSM-MAO) had quite different surface morphologies, thickness, and compositions compared to the MAO coating on as-received titanium alloy. Grain refinement and dislocation in the LSM-treated Ti6Al4V alloy provided extra energy and more numbers of discharge channels during the MAO process. LSM–MAO coating exhibited a more uniform pore distribution, relatively small pores, and larger thickness compared to the MAO coating. The LSM-MAO coating had higher hardness and better wear resistance than the MAO coating. LSM is deduced to be an appropriate and efficient pretreatment method for achieving a high-quality MAO coating on titanium alloy.Porous TiO2 ceramic coatings with high contents of Si and P were fabricated on a Ti6Al4V alloy using hybrid processing of laser surface melting (LSM) and microarc oxidation (MAO). The effect of LSM pretreatment on the growth behavior and mechanical properties of the MAO coating was studied. The results showed that the MAO coating on LSM pretreatment Ti6Al4V (LSM-MAO) had quite different surface morphologies, thickness, and compositions compared to the MAO coating on as-received titanium alloy. Grain refinement and dislocation in the LSM-treated Ti6Al4V alloy provided extra energy and more numbers of discharge channels during the MAO process. LSM–MAO coating exhibited a more uniform pore distribution, relatively small pores, and larger thickness compared to the MAO coating. The LSM-MAO coating had higher hardness and better wear resistance than the MAO coating. LSM is deduced to be an appropriate and efficient pretreatment method for achieving a high-quality MAO coating on titanium alloy.

Thermal management plays an important role in battery modules, especially under extreme operating conditions. Phase change materials (PCMs)-based cooling has been recognized as a promising approach that can prolong the life span of batteries and endure the passive thermal accumulation in the module. In this study, various mass fractions (0 wt%, 5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt%) of aluminum nitride (AlN) were added to composite PCMs to serve as heat-transfer promoters. The effect of the AlN additives on the thermal conductivity, mechanical properties, and volume resistivity were analyzed, and the root causes originating from the morphologies and structures of the composite PCMs were further examined. The results indicated that adding 20 wt% of the AlN in the composite PCMs was an optimal strategy. In addition, an AlN/paraffin (PA)/expanded graphite (EG)/epoxy resin composite PCMs-based 18650 LiFePO4 battery module was designed for thermal management. This battery module exhibited much better heat dissipation and temperature uniformity than an air-cooled battery module, leading to a 19.4% decrease of the maximum temperature and a less than 1 °C temperature difference at a high discharge rate of 3C. Thus, it could be concluded that the AlN-enhanced composite PCMs thermal management system exhibited a prominent controlling temperature and balancing temperature capacity for the battery module.

Intracellular tau accumulation forming neurofibrillary tangles is hallmark pathology of Alzheimer's disease (AD), but how tau accumulation induces synapse impairment is elusive. By overexpressing human full-length wildtype tau (termed hTau) to mimic tau abnormality as seen in the brain of sporadic AD patients, we found that hTau accumulation activated JAK2 to phosphorylate STAT1 (Signal Transducer and Activator of Transcription 1) at Tyr701 leading to STAT1 dimerization, nuclear translocation and its activation. STAT1 activation suppressed expression of N-methyl-D-aspartate receptors (NMDARs) through direct binding to the specific GAS element of GluN1, GluN2A and GluN2B promoters, while knockdown STAT1 by AAV-Cre in STAT1flox/floxmice or expressing dominant negative Y701F-STAT1 efficiently rescued hTau-induced suppression of NMDARs expression with amelioration of synaptic functions and memory performance. These findings indicate that hTau accumulation impairs synaptic plasticity through JAK2/STAT1-induced suppression of NMDARs expression, revealing a novel mechanism for hTau-associated synapse and memory deficits.

Non-toxigenic Bacteroides fragilis is regarded as a potential candidate for probiotic owing to its various advantages. We previously isolated a new strain of B. fragilis (ZY-312) and verified its biosafety and capability of inhibiting the growth of pathogens in vivo. However, the colonization of ZY-312 in gastrointestinal (GI) tract remains to be determined. To track the colonization of ZY-312, mice were gavaged with ZY-312 labeled by means of metabolic oligosaccharide engineering and bioorthogonal click chemistry or given AF647-dibenzocyclooctyne (DIBO) directly. Then the fluorescence was detected in GI tract, spleen and kidneys. Results showed that ZY-312 could be labeled by metabolic oligosaccharide engineering, and the optimal incubation time with AF647-DIBO was 5 h in vitro. Following oral gavage with AF647-DIBO labeled ZY-312 or AF647-DIBO alone, mice were subjected to in vivo imaging and the fluorescence intensity was similar in both groups 3 h, 6 h, and 12 h post the gavage. The fluorescence of AF647-DIBO group disappeared 24 h post gavage which was probably due to the excretion via GI tract. While the fluorescence of AF647-DIBO labeled ZY-312 retained in the cecum for as long as 48 h. Immunofluorescence assay further confirmed that labeled ZY-312 transiently colonized not only in cecum but also in stomach, ileum and colon of mice 48 h post-gavage and that no massive accumulation of ZY-312 was detected in other organs such as kidneys and spleen. In conclusion, ZY-312 could transiently colonize in GI tract, mainly in cecum, for at least 48 h, and it hardly disseminate to other organs, which shed new light on the future development of B. fragilis as a probiotic product.

A new aporphine, 3-hydroxyhernandonine (1) and a new lignin, 4&prime, O-demethyl-7-O-methyldehydropodophyllotoxin (2), have been isolated from the root wood of Hernanadia nymphaeifolia, together with thirteen known compounds (3&ndash, 15). The structures of these compounds were determined through mass spectrometry (MS) and spectroscopic analyses. The known isolate, 2-O-methyl-7-oxolaetine (3), was first isolated from natural sources. Among the isolated compounds, 3-hydroxyhernandonine (1), 4&prime, O-demethyl-7-O-methyldehydropodophyllotoxin (2), hernandonine (4), oxohernangerine (5), and oxohernagine (6) displayed inhibition (IC50 values &le, 5.72 &mu, g/mL) of superoxide anion production by human neutrophils in response to formyl-l-methionyl-l-leucyl-l-phenylalanine/cytochalasin B (fMLP/CB). In addition, 3-hydroxyhernandonine (1), 4&prime, O-demethyl-7-O-methyldehydropodophyllotoxin (2), oxohernangerine (5), and oxohernagine (6) suppressed fMLP/CB-induced elastase release with IC50 values &le, 5.40 &mu, g/mL.

In order to improve the processing efficiency and processing quality of silicon rods, and to optimize the process parameters during the cutting process of silicon rods, the sawing force of wire saw is studied from the aspects of cutting deformation and friction. Meanwhile, the mathematic model is established between the sawing force and some cutting process parameters. Besides, the quadratic regression model is also established by Box-Behnken center combination experiment and the response surface methodology(RSM), which can reflect the wire saw speed, workpiece feed rate and wire saw radius of the interaction of three process parameters on the wire saw sawing force. The results show that the model can accurately predict the sawing force and optimize the process parameters during the cutting process as well.

Map-based cloning was used to identify the ns gene, which was involved in the formation of cucumber numerous fruit spines together with other genes under regulation by plant hormone signal transduction. The cucumber (Cucumis sativus) fruit spine density has an important impact on the commercial value. However, little is known about the regulatory mechanism for the fruit spine formation. Here, we identified NUMEROUS SPINES (NS), which regulate fruit spine development by modulating the Auxin signaling pathway. We fine-mapped the ns using a 2513 F2 population derived from NCG122 (numerous fruit spines line) and NCG121 (few fruit spines line), and showed that NS encoded auxin transporter-like protein 3. Genetic diversity analysis of the NS gene in natural populations revealed that one SNP and one InDel in the coding region of ns are co-segregated with the fruit spine density. The NS protein sequence was highly conserved among plants, but its regulation of fruit spine development in cucumber seems to be a novel function. Transcriptome profiling indicated that the plant hormone signal transduction-related genes were highly enriched in the up-regulated genes in NCG122 versus NCG121. Moreover, expression pattern analysis of the auxin signal pathway-related genes in NCG122 versus NCG121 showed that upstream genes of the pathway (like ns candidate gene Csa2M264590) are down-regulated, while the downstream genes are up-regulated. Quantitative reverse transcription PCR confirmed the differential expression during the fruit spine development. Therefore, reduced expression of ns may promote the fruit spine formation. Our findings provide a valuable framework for dissecting the regulatory mechanism for the fruit spine development.

To evaluate the interlaboratory mass bias for high-precision stable Mg isotopic analysis of natural materials, a suite of silicate standards ranging in composition from felsic to ultramafic were analyzed in five laboratories by using three types of multicollector inductively coupled plasma mass spectrometer (MC-ICPMS). Magnesium isotopic compositions from all labs are in agreement for most rocks within quoted uncertainties but are significantly (up to 0.3‰ in 26Mg/24Mg, >4 times of uncertainties) different for some mafic samples. The interlaboratory mass bias does not correlate with matrix element/Mg ratios, and the mechanism for producing it is uncertain but very likely arises from column chemistry. Our results suggest that standards with different matrices are needed to calibrate the efficiency of column chemistry and caution should be taken when dealing with samples with complicated matrices. Well-calibrated standards with matrix elements matching samples should be used to reduce the interlaboratory mass bias.

Monodisperse micron-size poly(styrene-co-divinylbenzene) (PST-DVB) microspheres were successfully prepared by vibration dispersion. A vibrator was used to generate a controlled vibration to jet from a single nozzle of 200 µm to produce uniform droplets. The effects of variations in selected process parameters upon the droplets formation and the diameter of the microspheres were investigated. It was demonstrated that changes in the velocity of oil phase, drive frequency and destabilization amplitude have significant effects on the formation of uniform droplets and the average diameter of the microspheres. Rational polynomial regression equations of the above parameters were established. Based on these equations, we could calculate the operation conditions to produce uniform droplets with the desirable diameter.

In order to improve the extracellular endo-1,4-β-mannosidase (MAN) activity of recombinant Pichia pastoris, optimization of signal peptides was investigated. At first, five potential signal peptides (W1, MF4I, INU1A, αpre, HFBI) were chosen to be analyzed by SignalP 4.0, among which W1 was designed. Then, the widely used signal peptide α-factor in expression vector pGAPZαA was replaced by those five signal peptides to reconstruct five new expression vectors. MAN activity was assayed after expression vectors were transformed into Pichia pastoris. The data show that the relative efficiencies of W1, MF4I, INU1A, apre, and HFBI signal peptides are 23.5%, 203.5%, 0, 79.7%, and 120.3% compared with α-factor, respectively. The further gene copy number determination by the quantitative real-time PCR reveals that the MAN activities mediated by α-factor from 1 to 6 gene copy number levels are 12.95, 43.33, 126.63, 173.53, 103.23 and 88.63 U/mL, while those mediated by MF4I are 79.22, 133.89, 260.14, 347.5, 206.15 and 181.89 U/mL, respectively. The maximum MAN activity reached 347.5 U/mL with 4 gene copies mediated by MF4I. These results indicate that replacing the signal peptide α-factor with MF4I and increasing MAN gene copies to a proper number can greatly improve the secretory expression of MAN.

Magnesium isotopic compositions are reported for twenty-four international geological reference materials including igneous, metamorphic and sedimentary rocks, as well as phlogopite and serpentine minerals. The long-term reproducibility of Mg isotopic determination, based on 4-year analyses of olivine and seawater samples, was ≤ 0.07‰ (2s) for δ26Mg and ≤ 0.05‰ (2s) for δ25Mg. Accuracy was tested by analysis of synthetic reference materials down to the quoted long-term reproducibility. This comprehensive dataset, plus seawater data produced in the same laboratory, serves as a reference for quality assurance and inter-laboratory comparison of high-precision Mg isotopic data. Les compositions isotopiques du magnesium sont fournies pour vingt-quatre materiaux geologiques de reference internationaux, comprenant des roches ignees, metamorphiques et sedimentaires, ainsi qu'une phlogopite et des serpentines. La reproductibilite a long terme de la determination isotopique du Mg, basee des analyses sur quatre ans d’echantillons d'olivine et d'eau de mer, etait ≤ 0.07% (2s) pour δ26Mg et ≤ 0.05% (2s) pour δ25Mg. La precision a ete testee par l'analyse de materiaux de reference synthetiques jusqu’a la reproductibilite a long terme indiquee. Cette base de donnees complete, ainsi que des donnees d'eau de mer produites dans le meme laboratoire, servent de reference pour l'assurance qualite et la comparaison inter-laboratoires de haute precision des donnees isotopiques du Mg.

This present study is based on the single factor test and the significant factors of emulsification conditions, which influence the process of microencapsulation of B. bifidum BB28 and BB01, will be screen out by Plackett-Burman experimental. Bifidobacterium BB0I and BB28 were encapsulated by using emulsion method respectively. Several factors, such as alginate concentration, cell suspension-alginate ratios, CaCl2 concentration, Tween 80 concentration, emulsification time, encapsulating time and oil-water ratios have been investigated, the results showed that sodium alginate concentration, cell suspension-alginate ratios, encapsulating time and emulsification time have a significant effect for Bifidobacterium BB01 microcapsules; CaCl2 concentration, cell suspension-alginate ratios, sodium alginate concentration and emulsification time have a significant effect for Bifidobacterium BB28 microcapsules.

The experiments and numerical simulation were conducted for ZL205A aluminum alloy cylindrical shell casting. The formation mechanism of the linear segregation produced by the low pressure die casting (LPDC) process was investigated. And the heat transfer of the casting during solidification process was analyzed by simulation technique, resulting from the information of linear segregation obtained by plenty of experiments. The new linear segregation criterion was proposed through the simulation and experimental results. It was found that the melting metal with high Cu contents was feeding the crack shrinkage formed by the tearing under the effect of feeding pressure during the later solidification, which led to the formation of linear segregation. The control methods for the linear segregation were suggested based on the proposed mechanism. Finally, the criterion of linear segregation was confirmed by the production of the actual castings.

Interfacial carrier recombination is one of the dominant loss mechanisms in high efficiency perovskite solar cells, and has also been linked to hysteresis and slow transient responses in these cells. Here we demonstrate an ultrathin passivation layer consisting of a PMMA:PCBM mixture that can effectively passivate defects at or near to the perovskite/TiO2 interface, significantly suppressing interfacial recombination. The passivation layer increases the open circuit voltage of mixed-cation perovskite cells by as much as 80 mV, with champion cells achieving Voc ∼ 1.18 V. As a result, we obtain efficient and stable perovskite solar cells with a steady-state PCE of 20.4% and negligible hysteresis over a large range of scan rates. In addition, we show that the passivated cells exhibit very fast current and voltage response times of less than 3 s under cyclic illumination. This new passivation approach addresses one of the key limitations of current perovskite cells, and paves the way to further efficiency gains through interface engineering.

Hyperphosphorylated tau is the major protein component of neurofibrillary tangles in the brains of patients with Alzheimer’s disease (AD). However, the mechanism underlying tau hyperphosphorylation is not fully understood. Here, we demonstrated that exogenously expressed wild-type human tau40 was detectable in the phosphorylated form at multiple AD-associated sites in cytoplasmic and nuclear fractions from HEK293 cells. Among these sites, tau phosphorylated at Thr205 and Ser214 was almost exclusively found in the nuclear fraction at the conditions used in the present study. With the intracellular tau accumulation, the Ca(2+) concentration was significantly increased in both cytoplasmic and nuclear fractions. Further studies using site-specific mutagenesis and pharmacological treatment demonstrated that phosphorylation of tau at Thr205 increased nuclear Ca(2+) concentration with a simultaneous increase in the phosphorylation of Ca(2+)/calmodulin-dependent protein kinase IV (CaMKIV) at Ser196. On the other hand, phosphorylation of tau at Ser214 did not significantly change the nuclear Ca(2+)/CaMKIV signaling. Finally, expressing calmodulin-binding protein-4 that disrupts formation of the Ca(2+)/calmodulin complex abolished the okadaic acid-induced tau hyperphosphorylation in the nuclear fraction. We conclude that the intracellular accumulation of phosphorylated tau, as detected in the brains of AD patients, can trigger nuclear Ca(2+)/CaMKIV signaling, which in turn aggravates tau hyperphosphorylation. Our findings provide new insights for tauopathies: hyperphosphorylation of intracellular tau and an increased Ca(2+) concentration may induce a self-perpetuating harmful loop to promote neurodegeneration.

Oxidative stress and diabetes have a tendency to alter protein, lipid, and DNA moieties. One of the strategic methods used to reduce diabetes-associated oxidative stress is to inhibit the carbohydrate-digesting enzymes, thereby decreasing gastrointestinal glucose production. Plant-derived natural antioxidant molecules are considered a therapeutic tool in the treatment of oxidative stress and diabetes. The objective of this study was to identify tartary buckwheat rice flavonoids and evaluate the effect of in vitro digestion on their antioxidant and antidiabetic properties. High performance liquid chromatography (HPLC) analysis indicated the presence of rutin as a major component and quercitrin as a minor component of both digested and non-digested flavonoids. Both extracts showed a significant antioxidant capacity, but digested flavonoids showed reduced activity compared to non-digested. There were some decreases of the antioxidant activities (2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS), 2,2-diphenyl-1-picrylhydrazy (DPPH) radical, and ferric reducing antioxidant power (FRAP)) of digested tartary buckwheat rice flavonoids compared with non-digested. Flavonoids from both groups significantly inhibited reactive oxygen species (ROS) production and α-glucosidase activity. Both digested and non-digested flavonoids markedly increased glucose consumption and glycogen content in HepG2 cells. Tartary buckwheat rice flavonoids showed appreciable antioxidant and antidiabetic properties, even after digestion. Tartary buckwheat rice appears to be a promising functional food with potent antioxidant and antidiabetic properties.

The present work investigates the effect of the reheating temperature on the microstructure evolution and tensile properties of a magnesium composite reinforced by short carbon fibers. This composite was fabricated by semi-solid isothermal treatment and hot extrusion. The results indicate that the dynamic recrystallization grain size of the composite decreases with increasing reheating temperature, and there is strong interfacial bonding between the short carbon fibers and magnesium matrix. After reheating at 610 ?C for 30 min, the strength of the composite is significantly improved, particularly the yield strength. The refined grains and good interfacial bonding are responsible for the excellent strength of this composite.

Copper matrix composites consisting of chromium (Cr) or ferrochrome (Cr-Fe) as strengthening elements and molybdenum disulfide as a lubricant had been sintered in nitrogen and hydrogen atmosphere, respectively. Their morphology and energy-dispersive X-ray spectrometry (EDS) analysis showed that serious interaction occurred between MoS2 and Cr (or Cr-Fe) particles when the samples were sintered in hydrogen atmosphere. Chromium sulfide compound (Cr x S y ) was formed as a reaction product, which decreased the density and strength of the composites remarkably. This interaction was inhibited when the samples were sintered in nitrogen atmosphere; thus, the mechanical properties of the composites were improved.