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Silver nanowire (Ag NW)-based transparent back electrodes prepared via all solution-process are promising for bifacial and semitransparent perovskite solar cells (PSCs). However, the inadequate electrical contact between the silver nanowires themselves and the contact with substrate leads to reduced overall solar cell performance; meanwhile, serious corrosion of Ag NW in ambient environment restricting the further applications. In this work, polyvinylpyrrolidone (PVP) as a binder in Ag NW electrode significantly enhances the conductivity and transparency at the same time improving the interface electric contact. The PSC with PVP modified Ag NW electrode demonstrated frontside and backside efficiency approaching 18 % and 14.1 % (AM1.5, 1 Sun), respectively, which achieves 82 % efficiency with normal Ag device and bifacial factor of 79 %. The long-term storage stability of PSC is also improved by PVP protection. The final device structure is ITO/Ni O x /MeO/(FA0.92MA0.08)0.95Cs0.05Pb(I0.9Br0.1)3/PEAI/PC61BM/BCP/ Ag NW. This work highlights the method to fabricate robust transparent Ag NW electrode for bifacial perovskite solar cells. • Polyvinylpyrrolidone (PVP) in Ag nanowire (Ag NW) electrode significantly enhances the conductivity and transparency. • PVP modified Ag NW electrode improves the interface electric contact and charge transport of the solar cell. • The Perovskite solar cell (PSC) with PVP modified Ag NW electrode demonstrated high efficiency and bifacial factor. • The long-term storage stability of PSC is also improved by PVP protection. [ABSTRACT FROM AUTHOR]

The development of the mining industry and the overuse of inorganic fertilizers have led to an excess of manganese (Mn) in the soil, thereby, contaminating the soil environment and people's health. On heavy metal-contaminated soils, the combined arbuscular mycorrhizal fungi (AMF)-phytoremediation technique becomes a hotspot because of its environmentally friendly, in situ remediation. AMF inoculation often leads to a decrease in host Mn acquisition, which provides a basis for its application in phytoremediation of contaminated soils. Moreover, the utilization value of native AMF is greater than that of exotic AMF, because native AMF can adapt better to Mn-contaminated soils. In addition to the fact that AMF enhance plant Mn tolerance responses such as regionalization, organic matter chelation, limiting uptake and efflux, and so on, AMF also develop plant-independent fungal pathways such as direct biosorption of Mn by mycorrhizal hyphae, fungal Mn transporter genes, and sequestration of Mn by mycorrhizal hyphae, glomalin, and arbuscule-containing root cortical cells, which together mitigate excessive Mn toxicity to plants. Clarifying AMF-plant interactions under Mn stress will provide support for utilizing AMF as a phytoremediation in Mn-contaminated soils. The review reveals in detail how AMF develop its own mechanisms for responding to excess Mn and how AMF enhance plant Mn tolerance, accompanied by perspectives for future research. [Display omitted] • AMF inoculation diversely affects host Mn levels, dominated by reduced Mn uptake. • Mn-contaminated soils reduce AMF diversity, along with Glomus as the dominant genus and native AMF more tolerant. • AMF enhances plant Mn tolerance such as regionalization and chelation. • AMF hyphae have direct biosorption and sequestration of Mn. • Fungal Mn transporters, glomalin, and arbuscule-contained cortical cells mitigate Mn. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both laser/chlorine and laser/PS systems could efficiently degrade CBZ. • HO·, Cl· and ClO· were dominant for CBZ degradation in laser/chlorine system. • CBZ degradation in laser/PS system was primarily attributed to HO· and SO 4. -. • The degradation pathways of CBZ were proposed based on DFT analysis. Residual carbamazepine (CBZ) in water is difficult to remove through conventional treatment processes, threatening the safety of drinking water. Ultraviolet-based advanced oxidation processes (UV-AOPs) have shown promise in removing refractory organic pollutants, while the low energy and efficiency of traditional mercury lamps hinder their practical applications. In this study, the performance and mechanism of an intensive-energy light source, UV laser, were systematically explored in UV-AOPs (laser/chlorine, laser/persulfate (PS)). It was found that UV laser exhibited a significantly activating ability for chlorine and PS due to its precise wavelength and high pulse energy. When exposed to UV laser (266 nm, 4.2 mW/cm2) combined with 200 μM chlorine and PS, the kinetic rate constants for the degradation of 10 μM CBZ were determined to be 3.160 × 10-3 and 1.227 × 10-3 s−1, respectively. The degradation of CBZ was dominated by hydroxyl radicals (60.98 %) and sulfate radicals (23.15 %) in laser/PS system, while in laser/chlorine system, hydroxyl radicals (54.90 %), chlorine radicals (27.43 %), and chlorine oxide radicals (13.81 %) were primary reactive species. Furthermore, both the laser/chlorine and laser/PS systems demonstrated compatibility with a wide pH range of 5.0–9.0 and high resistance to anionic interference. Moreover, the electrophilic and nucleophilic sites of CBZ and energy barrier of the initial reaction were calculated based on the density functional theory (DFT). Additionally, the degradation pathways of CBZ and the toxicity of transformation products in laser/chlorine and laser/PS processes were proposed and evaluated. These results demonstrated that the UV laser-based processes exhibited promising prospects in eliminating refractory organic pollutants in water treatment. [ABSTRACT FROM AUTHOR]

Cell transplantation has brought about a breakthrough in the treatment of nerve injuries, and the efficacy of cell transplantation compared to drug and surgical therapies is very exciting. In terms of transplantation targets, the classic cells include neural stem cells (NSCs) and Schwann cells, while a class of cells that can exist and renew throughout the life of the nervous system - olfactory ensheathing cells (OECs) - has recently been discovered in the olfactory system. OECs not only encircle the olfactory nerves but also act as macrophages and play an innate immune role. OECs can also undergo reprogramming to transform into neurons and survive and mature after transplantation. Currently, many studies have confirmed the repairing effect of OECs after transplantation into injured nerves, and safe and effective results have been obtained in clinical trials. However, the specific repair mechanism of OECs among them is not quite clear. For this purpose, we focus here on the repair mechanisms of OECs, which are summarized as follows: neuroprotection, secretion of bioactive factors, limitation of inflammation and immune regulation, promotion of myelin and axonal regeneration, and promotion of vascular proliferation. In addition, integrating the aspects of harvesting, purification, and prognosis, we found that OECs may be more suitable for transplantation than NSCs and Schwann cells, but this does not completely discard the value of these classical cells. Overall, OECs are considered to be one of the most promising transplantation targets for the treatment of nerve injury disorders. [ABSTRACT FROM AUTHOR]

Background: The role of an adverse maternal environment (AME) in conjunction with a postweaning Western diet (WD) in the development of nonalcoholic fatty liver disease (NAFLD) in adult offspring has not been explored. Likewise, the molecular mechanisms associated with AME-induced NAFLD have not been studied. The fatty acid translocase or cluster of differentiation 36 (CD36) has been implicated to play a causal role in the pathogenesis of WD-induced steatosis. However, it is unknown if CD36 plays a role in AME-induced NAFLD.Objective: This study was designed to evaluate the isolated and additive impact of AME and postweaning WD on the expression and DNA methylation of hepatic Cd36 in association with the development of NAFLD in a novel mouse model.Methods: AME constituted maternal WD and maternal stress, whereas the control (Con) group had neither. Female C57BL/6J mice were fed a WD [40% fat energy, 29.1% sucrose energy, and 0.15% cholesterol (wt/wt)] 5 wk prior to pregnancy and throughout lactation. Non invasive variable stressors (random frequent cage changing, limited bedding, novel object, etc.) were applied to WD dams during the last third of pregnancy to produce an AME. Con dams consumed the control diet (CD) (10% fat energy, no sucrose or cholesterol) and were not exposed to stress. Male offspring were weaned onto either CD or WD, creating 4 experimental groups: Con-CD, Con-WD, AME-CD, and AME-WD, and evaluated for metabolic and molecular parameters at 120 d of age.Results: AME and postweaning WD independently and additively increased the development of hepatic steatosis in adult male offspring. AME and WD independently and additively upregulated hepatic CD36 protein and mRNA expression and hypomethylated promoters 2 and 3 of the Cd36 gene.Conclusions: Using a mouse AME model together with postweaning WD, this study demonstrates a role for CD36 in AME-induced NAFLD in offspring and reveals 2 regions of environmentally induced epigenetic heterogeneity within Cd36. [ABSTRACT FROM AUTHOR]

With escalating demand for urban parking structures, the columns within these structures are more susceptible to hazards resulting from vehicle collisions compared to other public buildings. Moreover, it is crucial to emphasize the significant increase in the risk of collapse in parking structures subjected to vehicle collisions, primarily owing to their heightened dynamic response and low required bearing capacity. Consequently, to prevent vehicles from directly crashing on the columns, besides providing an alternate load path, urgent implementation of protective measures utilizing energy-absorbing materials is necessary for parking structures. This study proposes a honeycomb panel-based (HP) protective device for steel parking structures aimed at absorbing energy and mitigating damage resulting from vehicle collisions. A simplified multi-scale simulation, considering reasonable material models and boundary conditions, is employed to study the performance of parking structures under transverse impact. The deformation patterns, impact loads, transverse deflections, internal energies, and horizontal reactions are compared for the parking structures with and without the HP protective devices. Innovatively, a classical progressive collapse loading scheme is employed to simulate the vertical residual resistance of the beam-column substructure after the transverse impact. Finally, a comprehensive investigation is conducted on the effects of critical parameters of HP protective device. The results demonstrate that a properly designed HP protective device can significantly enhance the resistance of parking structures to transverse impact, thereby effectively mitigating the risk of progressive collapse in such structures after impact. • A honeycomb panel-based (HP) protective device for steel parking structures is proposed. • A simplified multi-scale simulation considering reasonable material and boundary is employed. • A vertical residual resistance of substructure after transverse impact is innovatively simulated. • The HP protective device with a reasonable design can present a noticeable protective effect. [ABSTRACT FROM AUTHOR]

Titanium-based gradient bioceramic coating fabricated by laser cladding has been studied due to its excellent comprehensive performance and potential value in biomaterials. However, pore sizes of the coating prepared using traditional laser cladding technique are typically too small which can reduce its osteogenesis performance. To address this issue, a porous gradient bioceramic coating is successfully prepared on a titanium alloy surface by adding a pore-forming agent to the coating powder with subsequent laser cladding process. The bioceramic coating prepared with the optimized processing conditions (output power P = 1.8 kW, scanning speed V = 240 mm/min, and spot diameter D = 4 mm) exhibits a flat surface that comprises of a uniform enamel microstructure. The coating is metallurgically bonded to the substrate with a low number of microcracks. When the amount of pore-forming agent A = 2.5 wt%, the distribution of pores in coating becomes more uniform. When A = 2.5 to 10 wt%, the most probable pore size is 2.5 μm. It is shown that pore-forming agent quantity A = 2.5 wt% has a significant advantage in producing more large-sized pores in the coating. The number of pores in coating shows a trend of decreasing first, then increasing, and then decreasing. The coating phase consists of HA, β-TCP, TiO 2 , CaTiO 3 , etc., which is consistent with the coating material without pore-forming agent. In general, microhardness gradually decreases with increasing pore-forming agent quantity. The maximum microhardness values of coatings with and without pore-forming agent are 976 HV 0.2 and 2086 HV 0.2 , respectively. Therefore, with the addition of a suitable amount of pore-forming agent, a porous bioceramic coating can be fabricated by an optimized laser cladding technique. This porous morphology will be beneficial for improving the osteogenic properties of the coating. [ABSTRACT FROM AUTHOR]

In this paper, we study the influence of the parameters for the accelerating Kerr-Newman black hole on the shadows and the constraints, extensively. We find that the rotating parameter a , the charge parameter e , and the inclination angle θ 0 affect the shadow qualitatively similar to that of Kerr-Newman black holes. The result shows that the size of the shadow will scale down with the accelerating factor A. Besides, the factor A also can affect the best viewing angles, which make the observations maximum deviate from θ 0 = π 2 , and the degree of the deviations are less than 1%. Then, we assume the M87* as an accelerating Kerr-Newman black hole with the mass M = 6.5 × 10 9 M ⊙ and the distance r 0 = 16.8 M p c. Combining the EHT observations, we find that neither the observations, circularity deviation Δ C or axial ratio D x can distinguish the accelerating black hole or not. However, the characteristic areal-radius of the shadow curve R a can give corresponding constraints on the parameters of the accelerating Kerr-Newman black hole. The result shows that the bigger accelerating factor A is, the stronger constraints on the rotating parameter a and charged parameter e. The maximum range of the accelerating factor is A r 0 ≤ 0.558 for a accelerating Schwarzschild case with (a / M = e / M = 0) , and for an extremely slow accelerating case (A r 0 ≤ 0.01) , the ranges of rotating parameter a and charged parameter e are a / M ∈ (0 , 1) and e / M ∈ (0 , 0.9). [ABSTRACT FROM AUTHOR]

Abstract Recent research has demonstrated that cardiovascular deconditioning (i.e., cardiac atrophy and hypovolemia) contributes significantly to the Postural Orthostatic Tachycardia Syndrome (POTS) and its functional disability. Therefore, physical reconditioning with exercise training and volume expansion via increased salt and fluid intake should be initiated early in the course of treatment for patients with POTS if possible. The use of horizontal exercise (e.g., rowing, swimming, recumbent bike, etc.) at the beginning is a critical strategy, allowing patients to exercise while avoiding the upright posture that elicits their POTS symptoms. As patients become increasingly fit, the duration and intensity of exercise should be progressively increased, and upright exercise can be gradually added as tolerated. Supervised training is preferable to maximize functional capacity. Other non-pharmacological interventions, which include: 1) chronic volume expansion via sleeping in the head-up position; 2) reduction in venous pooling during orthostasis by lower body compression garments extending at least to the xiphoid or with an abdominal binder; and 3) physical countermeasure maneuvers, such as squeezing a rubber ball, leg crossing, muscle pumping, squatting, negative-pressure breathing, etc., may also be effective in preventing orthostatic intolerance and managing acute clinical symptoms in POTS patients. However, randomized clinical trials are needed to evaluate the efficacies of these non-pharmacological treatments of POTS. [ABSTRACT FROM AUTHOR]

The two-tone frequency modulation spectroscopy (TTFMS) is widely used for gas trace detection with its low noise absorption signal. In this paper we propose and implement the TTFMS scheme for frequency offset locking a single diode laser to an atomic resonance line by using its dispersion signal. The TTFMS theory is first discussed under the assumption that the intermediate modulation frequency is comparable to the linewidth of the absorption feature, and the dependence of the TTFMS absorption and dispersion features on the intermediate modulation frequency and modulation index are investigated theoretically. Based on a fiber-coupled electro-optic modulator (EOM) with two-tone modulation, we experimentally demonstrated the performance of the frequency offset locking method. The result shows a short-term frequency stability of the frequency offset locked laser reached around 1.1 × 10 −11 , with an averaging time of 2 s. This method can find wide applications in fields requiring widely tunable frequency offset locking a single laser to the atomic resonance line, like precision spectroscopy and Raman optics for atom interferometers. [ABSTRACT FROM AUTHOR]

Abstract Sodium-ion batteries are widely regarded as an alternative to lithium ion batteries, especially in large-scale energy storage applications. Developing a negative electrode material with high specific capacity and excellent cyclic stability is one of the most pressing problems for sodium-ion batteries. Herein, nitrogen and phosphorous dual-doped graphene aerogel (NPGA) is fabricated via a low temperature phosphidation of NH 2 -rich graphene aerogel precursor. Expanded interlayer spacing of 0.39 nm and high content of pyridinic-N are obtained in this architecture. These features lead to high sodium storage performance of NPGA, however, in a wide potential range. A large reversible capacity of 330 mAh g−1 at 50 mA g−1, and good rate capability of 218 mAh g−1 at 1 A g−1 and 189 mAh g−1 at 3 A g−1 can be achieved in the potential range from 0.005 to 3.0 V (vs. Na/Na+). Moreover, it delivers ultra-stable capacities of 195 mAh g−1 at 1 A g−1 after 1000 cycles and 132 mAh g−1 at 5 A g−1 after 2000 cycles. It should be underlined that in practice only half of this capacity values could be utilized in Na-ion accumulators, i.e., the capacity supplied from 0.005 to 1.5 V (vs. Na/Na+). The attractive electrochemical performance should be ascribed to the remarkable capacitive contribution. This strategy would be readily applied to construct high-performance carbonaceous anodes for sodium-ion batteries and/or electrochemical capacitors. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract For a high-current Radio Frequency Quadrupole (RFQ) accelerator, space charge will strongly affect the stability of beams, which brings challenges and difficulties to the beam dynamics design. For an in-depth study of this space charge effect, a project has been proposed by Peking University and the Institute of Modern Physics of the Chinese Academy of Sciences. This project requires a 162.5 MHz RFQ to accelerate a 100-mA continuous-wave (CW) proton beam to 3 MeV. The beam dynamics design of this RFQ is based on the four-section procedure with improved radial focusing strength along the RFQ. We have investigated the relationship between limiting current and beam transmission to analyze the reasons for emittance growth and beam loss. We have also carried out an irradiation experiment based on this beam dynamics design to study the irradiation damage of the electrode surface, as this can be one main reason for reduced transmission or unstable operation that most existing high-current RFQs encounter after long-time operation. The results show that low-energy beam losses need to be kept as low as possible to prolong the life of the RFQ electrodes. The final simulated transmission efficiency reached 99.8%, as confirmed by the code toutatis. [ABSTRACT FROM AUTHOR]

• The magnetic property and magnetocaloric effect of the rare-earth based metallic glasses R 55 Co 30 Al 10 Si 5 (R = Ho, Dy) ribbons were studies. • The typical spin glass behavior is observed in the metallic glasses R 55 Co 30 Al 10 Si 5 (R = Ho, Dy) ribbons. • The glass forming ability (GFA) of R 55 Co 30 Al 10 Si 5 (R = Ho, Dy) was evaluated by DSC traces. • The significant - Δ S M m a x and RC values make the metallic glasses R 55 Co 30 Al 10 Si 5 ribbons a promising hydrogen liquefaction magnetic refrigerant for applications. Metallic glass alloys are suitable systems for the development of magnetocaloric refrigerated materials due to the stable physical properties and the adjustable magnetic phase transition temperature. Here, the glass formation ability (GFA), magnetic properties and magnetocaloric effects of R 55 Co 30 Al 10 Si 5 (R = Ho, Dy) amorphous ribbons prepared by the melt-spinning technique were investigated. The X-ray diffraction and DSC measurement indicated that the metallic glass alloys have a completely amorphous structure and excellent glass formation ability. The amorphous ribbons were demonstrated to undergo a second-order magnetic phase transition (ferromagnetic to paramagnetic) around T c ∼ 18 K for Ho 55 Co 30 Al 10 Si 5 , ∼34 K for Dy 55 Co 30 Al 10 Si 5 , respectively. The maximum magnetic entropy change (- Δ S M max) and the corresponding refrigerant capacity (RC) values are 12.7 J/kg K, 343 J/kg for Ho 55 Co 30 Al 10 Si 5 , 9.1 J/kg K, 334 J/kg for Dy 55 Co 30 Al 10 Si 5 under a field change Δ H = 5 T. The large - Δ S M max and high RC suggest that R 55 Co 30 Al 10 Si 5 (R = Ho, Dy) amorphous ribbons have potential applications in low temperature magnetic refrigeration. [ABSTRACT FROM AUTHOR]

Biocorrosion of X80 steel for Desulfovibrio desulfuricans and Pseudomonas stutzeri under elastic stress and yield stress was performed in neutral soil environment. Electrochemical results showed that yield stress resulted in higher corrosion rate for X80 specimens compared to elastic stress. When both yield stress and Desulfovibrio desulfuricans were applied to the specimens, the surface pit diameter and depth of the X80 specimens were the largest of all conditions and numerous secondary pits appeared at the bottom of primary pits. However, the introduction of Pseudomonas stutzeri significantly reduced the corrosion caused by Desulfovibrio desulfuricans. • Yield stress causes more serious corrosion damage than elastic stress. • SRB and yield stress synergistically lead to the formation of secondary pits. • The synergistic effect of SRB and stress is greater than Pseudomonas stutzeri. • Pseudomonas stutzeri can significantly reduce the pit depth caused by SRB. [ABSTRACT FROM AUTHOR]

The sustainable use of ecosystem services (ES) can contribute to enhancing human well-being. Understanding the effects of land use and climate change on ES can provide scientific and targeted guidance for the sustainable use of ES. The objective of this study was to reveal the way in which land use and climate change influence the spatial and temporal variations of ES in the mountain-oasis-desert system (MODS). In this study, we assessed water yield, soil conservation, crop production, and sand fixation in 1990, 2000, and 2010 in Altay Prefecture, which is representative of the MODS, based on widely used biophysical models. Moreover, we analyzed the effects of different land use and climate change conditions on ES. The results show that the area of forest and bare land decreased in Altay Prefecture. In contrast, the area of grassland with low coverage and cropland increased. The climate of this area presented an overall warming-wetting trend, with warming-drying and cooling-wetting phenomena in some areas. Soil conservation in the mountain zone, water yield in the oasis zone, and sand fixation in the desert zone all decreased under the influence of land use change alone. The warming-drying trend led to decreased water yield in the oasis zone and increased wind erosion in the desert zone. Based on the results, we recommend that local governments achieve sustainable use of ES by planting grasslands with high coverage in the oasis zone, increasing investment in agricultural science and technology, and establishing protected areas in the mountain and desert zones. The methodology in our study can also be applied to other regions with a MODS structure. [ABSTRACT FROM AUTHOR]

We fabricated the Tm 20 Ho 20 Gd 20 Ni 20 Al 20 ribbons by melt-spun technology and determined its glass forming ability (GFA), magnetic properties, magnetic phase transition (MPT) character, and magnetocaloric performance. The Tm 20 Ho 20 Gd 20 Ni 20 Al 20 melt-spun ribbon exhibits fully amorphous nature and excellent GFA. A second order (SO) type MPT from ferromagnetic to paramagnetic was observed around the Curie temperature of 30.3 K. Moreover, considerable MCE and magnetocaloric performance in Tm 20 Ho 20 Gd 20 Ni 20 Al 20 amorphous ribbon were realized with the maximum magnetic entropy change, temperature-averaged entropy change of 10 K lift, and relative cooling powder/refrigerant capacity of 9.4 J/kgK, 9.0 J/kgK, and 527.2/422.1 J/kg under 0–5 T field change, respectively. These magnetocaloric parameters are close to most of the recently reported magnetocaloric materials, which made the Tm 20 Ho 20 Gd 20 Ni 20 Al 20 amorphous HE ribbon amorphous ribbon also of potential for practical cryogenic MR applications. • The amorphousized Tm 20 Ho 20 Gd 20 Ni 20 Al 20 ribbons were fabricated. • Magnetic properties and MCE in Tm 20 Ho 20 Gd 20 Ni 20 Al 20 amorphous ribbon were studied. • Tm 20 Ho 20 Gd 20 Ni 20 Al 20 ribbons are potential for practical cryogenic MR applications. [ABSTRACT FROM AUTHOR]

• ε-Al x Fe 2-x O 3 (x = 0, 0.125, 0.167, 0.222 and 0.4) nanoparticles were prepared by a new kind of mesoporous template-compacted fumed silica. • The doping of Al3+ can decrease the size of ε-Fe 2 O 3 nanoparticles and effectively reduce the formation of α-Fe 2 O 3 impurity in the samples. • With the increase of Al3+ content, the coercivity of ε-Al x Fe 2-x O 3 increases firstly to a maximum and then decreases. • The magnetic phase transition temperature of the ε-Al x Fe 2-x O 3 samples decreases with the increase of Al3+ and finally vanishes. ε-Al x Fe 2-x O 3 (x = 0, 0.125, 0.167, 0.222 and 0.4) nanoparticles were manufactured by a new kind of mesoporous template-compacted fumed silica. The effect of Al3+ composition on the purity and magnetic performances of the ε-Al x Fe 2-x O 3 samples were investigated. The structural and magnetic performances of the samples were characterized by X-ray diffraction, transmission electron microscope and SQUID magnetometer. The results indicate that the doping of Al3+ can decrease the dimension of ε-Fe 2 O 3 nanoparticles and effectively reduce the formation of α-Fe 2 O 3 impurity in the samples. And the magnetic phase transition temperature of the ε-Al x Fe 2-x O 3 samples decreases with the increase of Al3+. And the low temperature magnetic phase transition finally vanishes at x = 0.222. The ε-Al x Fe 2-x O 3 samples exhibit large coercivity. With the increase of Al3+ content, the coercivity of ε-Al x Fe 2-x O 3 increases firstly to a maximum and then decreases. [ABSTRACT FROM AUTHOR]

To investigate the hot deformation behaviors of a nickel-based superalloy, the hot compressive tests are conducted at the deformation temperature range of 920–1040 °C and strain rate range of 0.001-1s −1 . It is found that the effects of strain rate and deformation temperature on the grain boundary maps are significant. An almost competed dynamic recrystallization (DRX) microstructure occurs at relatively low strain rates. However, the increased strain rate easily leads to the uneven microstructures. The DRX degree notably increases with the increase of deformation temperature, because the high temperature enhances the grain boundary migration mobility and facilitates the nucleation and growth of DRX grains. Based on the experimental results, multi-gene genetic programming (MGGP), artificial neural network (ANN) and Arrhenius type phenomenological models are established to predict the flow stress. Due to the obvious over-fitting problem of MGGP model, a Hannan-Quinn information criterion based MGGP (HQC-MGGP) approach is proposed. The performances of MGGP, HQC-MGGP, ANN and phenomenological models are compared. It is found that HQC-MGGP model has the best performance to predict the flow stress under the experimental conditions. Therefore, HQC-MGGP model is accurate and reliable in describing the hot deformation behaviors of the studied nickel-based superalloy. [ABSTRACT FROM AUTHOR]

The effects of Desulfovibrio desulfurican (D. desulfurican) and Pseudomonas stutzeri (P. stutzeri) on the biocorrosion of X80 pipeline steel for different nitrate and nitrite concentrations were studied. After treatment with nitrate and nitrite, the number of D. desulfurican cells decreased rapidly, and the inhibition effect of nitrite was more significant. However, the samples treated with nitrate suffered serious pitting corrosion, while the surface of the samples treated with nitrite formed γ-Fe 2 O 3 passivation films, which hindered the formation of erosion pits. Furthermore, nitrite also resulted in a significant decrease in the content of FeS, which was helpful to reduce corrosion. • Nitrate weakens SRB corrosion but enhances NRB corrosion. • Nitrite can passivate the steel surface to prevent corrosion. • The production of sulfide can be greatly inhibited by nitrite. • Nitrite treatment of SRB corrosion is superior to nitrate. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenides (2D TMDCs) has aroused tremendous attention in recent years, because of their remarkable properties originated from their unique structure. In this review we report the synthesis, characterization and applications of monolayer MoS 2 and WS 2 . [ABSTRACT FROM AUTHOR]

Due to the outstanding bioactivity and biocompatibility, calcium phosphate (CaP) based materials have been widely investigated for applications in the biomedical fields. In this study, amorphous calcium phosphate (ACP) nanospheres and hydroxyapatite (HA) nanorods have been prepared and hybridized with poly( d , l -lactic acid) (PLA) to fabricate the composite nanofibers through electrospinning. The as-prepared ACP-PLA and HA-PLA composite nanofibers exhibit favorable mineralization behaviors in simulated body fluid (SBF). In the mineralization process, the ACP nanospheres and HA nanorods play an important role in the formation of HA nanosheets on the surface of composite nanofibers. The ACP-PLA and HA-PLA composite nanofibers show a high biocompatibility. The in vivo bone defect repair properties of the ACP-PLA and HA-PLA composite nanofibers are preliminarily investigated. The as-prepared ACP-PLA and HA-PLA composite nanofibers have promising applications in the biomedical fields. [ABSTRACT FROM AUTHOR]

• Microbial corrosion of X80 pipeline steel is studied. • Either SRB or NRB leads to pitting corrosion of X80 steel. • Biologically competitive exclusion process of SRB and NRB is revealed. • Nitrite, a metabolite of NRB, can chemically remove sulfide. In this paper, we have investigated the corrosion mechanism of X80 carbon steel in the presence of nitrate reducing bacteria (NRB), sulfate reducing bacteria (SRB) or both in the Shenyang soil solution. The results show that both SRB and NRB increase the corrosion rate of steel specimens and cause pitting corrosion of steel. Electrochemical tests and weight-loss data show that the addition of NRB in the SRB-containing environment leads to the reduction of corrosion. The thermodynamic analyses confirm the competitive advantage of NRB for the nutrients (organic carbon sources and irons) and the chemical oxidation of ferrous sulfide by nitrite, which results in a mitigation in the microbiologically influence corrosion (MIC) of SRB. [ABSTRACT FROM AUTHOR]

Experiments were performed to better understand the role of environmental factors on reaction pathways and corresponding carbon isotope fractionations during abiotic hydrothermal synthesis of organic compounds using piston cylinder apparatus at 750 °C and 5.5 kbars. Chemical compositions of experimental products and corresponding carbon isotopic values were obtained by a Pyrolysis–GC–MS–IRMS system. Alkanes (methane and ethane), straight-chain saturated alcohols (ethanol and n -butanol) and monocarboxylic acids (formic and acetic acids) were generated with ethanol being the only organic compound with higher δ 13 C than CO 2 . CO was not detected in experimental products owing to the favorable water–gas shift reaction under high water pressure conditions. The pattern of δ 13 C values of CO 2 , carboxylic acids and alkanes are consistent with their equilibrium isotope relationships: CO 2 > carboxylic acids > alkanes, but the magnitude of the fractionation among them is higher than predicted isotope equilibrium values. In particular, the isotopic fractionation between CO 2 and CH 4 remained constant at ∼31‰, indicating a kinetic effect during CO 2 reduction processes. No “isotope reversal” of δ 13 C values for alkanes or carboxylic acids was observed, which indicates a different reaction pathway than what is typically observed during Fischer–Tropsch synthesis under gas phase conditions. Under constraints imposed in experiments, the anomalous 13 C isotope enrichment in ethanol suggests that hydroxymethylene is the organic intermediate, and that the generation of other organic compounds enriched in 12 C were facilitated by subsequent Rayleigh fractionation of hydroxymethylene reacting with H 2 and/or H 2 O. Carbon isotope fractionation data obtained in this study are instrumental in assessing the controlling factors on abiotic formation of organic compounds in hydrothermal systems. Knowledge on how environmental conditions affect reaction pathways of abiotic synthesis of organic compounds is critical for understanding deep subsurface ecosystems and the origin of organic compounds on Mars and other planets. [ABSTRACT FROM AUTHOR]

Patients with the Postural Orthostatic Tachycardia Syndrome (POTS) have orthostatic intolerance, as well as exercise intolerance. Peak oxygen uptake (VO 2peak ) is generally lower in these patients compared with healthy sedentary individuals, suggesting a lower physical fitness level. During acute exercise, POTS patients have an excessive increase in heart rate and reduced stroke volume for each level of absolute workload; however, when expressed at relative workload (%VO 2peak ), there is no difference in the heart rate response between patients and healthy individuals. The relationship between cardiac output and VO 2 is similar between POTS patients and healthy individuals. Short-term (i.e., 3 months) exercise training increases cardiac size and mass, blood volume, and VO 2peak in POTS patients. Exercise performance is improved after training. Specifically, stroke volume is greater and heart rate is lower at any given VO 2 during exercise after training versus before training. Peak heart rate is the same but peak stroke volume and cardiac output are greater after training. Heart rate recovery from peak exercise is significantly faster after training, indicating an improvement in autonomic circulatory control. These results suggest that patients with POTS have no intrinsic abnormality of heart rate regulation during exercise. The tachycardia in POTS is due to a reduced stroke volume. Cardiac remodeling and blood volume expansion associated with exercise training increase physical fitness and improve exercise performance in these patients. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Br−-ABTS method was based on the oxidative coloration of ABTS by Br−-induced PMS. • The Br−-ABTS method was convenient, rapid, accurate, and sensitive. • The Br−-ABTS method could measure as low as 0.03 μM PMS concentration. • The Br−-ABTS method tolerated the interference of water matrix. • The Br−-ABTS method was more flexible than DPD method for monitoring PMS concentration. A sensitive spectrophotometric method (the Br−-ABTS method) for measuring monopersulfate (PMS) of 0–20 μM in water was established. The Br−-ABTS method was based on the oxidation coloration reaction where Br− as catalyst promoted PMS for oxidation of ABTS forming the green-colored ABTS radical (ABTS•+) under pH 3.0 (50 mM phosphate buffer). ABTS•+ could be quantitatively measured at 415 nm, 650 nm, 732 nm and 820 nm using UV–vis spectrophotometer. There was a well linear relationship between the absorbance of ABTS•+ and PMS concentration with the value of R2 being 0.999. The proposed Br−-ABTS method was highly sensitive, and the absorbance generated by Br−-ABTS at 415 nm was 6.59 × 104 cm−1 per M (mol L–1) of PMS. The changes of pH from 3.0 to 9.0 had an insignificant effect on the calibration curve of Br−-ABTS method. The reaction of PMS with ABTS had a stoichiometric coefficient of 1:1.96 at the pH 3.0. The residual absorbance of ABTS•+ in ultrapure water, Xiangjiang water and Hou-lake water was stable within 30 min. Moreover, the trace PMS concentration of 0.03–20 μM in ultrapure water, 0.05–20 μM in natural water (e. g. Xiangjiang water and Hou-lake water) and 1–20 μM in wastewater was accurately measured with the proposed Br−-ABTS method. Additionally, the interference of natural water matrix (e. g. humic acid), metal ions (e. g. Co(II), Fe(III) and Cu(II)) and hydroxylamine had barely interference for the proposed Br−-ABTS method. Furthermore, the Br−-ABTS method was more accurate and flexible to determine PMS concentration than DPD method during the decolorization of rhodamine B in the Co(II)/PMS system, Cu(II)/PMS system and hydroxylamine/Fe(III)/PMS process. [ABSTRACT FROM AUTHOR]

Abstract: The new ruthenium (II) phosphine complexes (η6-C6H6)RuCl2[μ- (PPh2CH2N)2CH2(C10H6)]RuCl2(η6-C6H6) (1) and RuCl2(PPh3)[(PPh2CH2N)2CH2(C10H6)] (2) were synthesized and characterized by 1H NMR, 31P {1H} NMR and elemental analysis. Moreover, the structure of ruthenium (II) phosphine complex 1 was confirmed by X-ray crystallography. With complex 1 as the catalyst, the transfer hydrogenation of ketones reacted well, affording the corresponding alcohols in good yields under mild conditions. [Copyright &y& Elsevier]

Patients with post-traumatic stress disorder (PTSD) have an increased risk for cardiovascular disease. The underlying mechanisms are unclear but impaired autonomic function may contribute. However, research in this field has shown contradictory results and the causal links between PTSD, autonomic dysfunction, and cardiovascular risk remain unknown. This brief review summarizes the current knowledge on alterations in autonomic function and cardiovascular risk in patients with PTSD. A PubMed search of the literature was performed using the following keywords: autonomic function, heart rate variability, blood pressure variability, sympathetic activity, baroreflex function, and cardiovascular risk in combination with PTSD. Evidence-based studies conducted between 2000 and 2021 were selected. In total 1221 articles were identified and of these, 61 (48 original research papers, 13 review articles) were included in this review. Many, though not all, studies have reported increased activity of the sympathetic nervous system and decreased activity of the parasympathetic nervous system (namely, autonomic imbalance) in PTSD patients. There seems to be enough evidence to suggest impairments in baroreflex function in PTSD, leading to blood pressure dysregulation. It appears that the chronicity of PTSD diagnosis and symptom severity are independent risk factors for cardiovascular disease, which may be linked with impaired autonomic function. Increased cardiovascular risk may be associated with autonomic dysfunction in PTSD. Whether autonomic dysfunction can serve as a biomarker for the onset and progression of PTSD remains to be determined. It also needs to determine if autonomic imbalance increases the risk of developing PTSD. [ABSTRACT FROM AUTHOR]

[Display omitted] • The corrosion of X80 pipeline steel by alternating current (AC) and nitrate reducing bacteria (NRB) is studied. • Either AC or NRB lead to pitting corrosion of X80 steel. • The cooperation of AC and NRB results in larger and deeper pits on the steel surface. • In the AC environment containing NRB, the samples have the deepest pitting pits and the highest corrosion rate. In this work, electrochemical measurements and surface analysis techniques were used to investigate the effects of alternating current (AC) and nitrate reducing bacteria (NRB) on the corrosion behavior of X80 pipeline steel in the Shenyang soil extract solution. Either AC or NRB increases the corrosion rate of X80 steel samples, and the combination of AC and NRB can make the corrosion rate reach about 16.5 times of that without AC and NRB. Confocal laser scanning microscopy (CLSM) images show that the maximum pitting depth is up to 38.3 μm through the synergistic effect of AC and NRB. The data in this paper strongly confirms that AC and NRB synergistically accelerate the pitting formation of X80 pipeline steel, and lead to the generation of deeper and larger pits. [ABSTRACT FROM AUTHOR]

Abstract: In order to evaluate the extent of CO2–water–rock interactions in geological formations for C sequestration, three batch experiments were conducted on alkali feldspars–CO2–brine interactions at 150–200°C and 300bars. The elevated temperatures were necessary to accelerate the reactions to facilitate attainable laboratory measurements. Temporal evolution of fluid chemistry was monitored by major element analysis of in situ fluid samples. SEM, TEM and XRD analysis of reaction products showed extensive dissolution features (etch pits, channels, kinks and steps) on feldspars and precipitation of secondary minerals (boehmite, kaolinite, muscovite and paragonite) on feldspar surfaces. Therefore, these experiments have generated both solution chemistry and secondary mineral identity. The experimental results show that partial equilibrium was not attained between secondary minerals and aqueous solutions for the feldspar hydrolysis batch systems. Evidence came from both solution chemistry (supersaturation of the secondary minerals during the entire experimental duration) and metastable co-existence of secondary minerals. The slow precipitation of secondary minerals results in a negative feedback in the dissolution–precipitation loop, reducing the overall feldspar dissolution rates by orders of magnitude. Furthermore, the experimental data indicate the form of rate laws greatly influence the steady state rates under which feldspar dissolution took place. Negligence of both the mitigating effects of secondary mineral precipitation and the sigmoidal shape of rate–ΔGr relationship can overestimate the extent of feldspar dissolution during CO2 storage. Finally, the literature on feldspar dissolution in CO2-charged systems has been reviewed. The data available are insufficient and new experiments are urgently needed to establish a database on feldspar dissolution mechanism, rates and rate laws, as well as secondary mineral information at CO2 storage conditions. [Copyright &y& Elsevier]

Objectives: The purpose of this study was to test the hypothesis that a small heart coupled with reduced blood volume contributes to the postural orthostatic tachycardia syndrome (POTS) and that exercise training improves this syndrome. Background: Patients with POTS have marked increases in heart rate during orthostasis. However, the underlying mechanisms are unknown and the effective therapy is uncertain. Methods: Twenty-seven POTS patients underwent autonomic function tests, cardiac magnetic resonance imaging, and blood volume measurements. Twenty-five of them participated in a 3-month specially designed exercise training program with 19 completing the program; these patients were re-evaluated after training. Results were compared with those of 16 healthy controls. Results: Upright heart rate and total peripheral resistance were greater, whereas stroke volume and cardiac output were smaller in patients than in controls. Baroreflex function was similar between groups. Left ventricular mass (median [25th, 75th percentiles], 1.26 g/kg [1.12, 1.37 g/kg] vs. 1.45 g/kg [1.34, 1.57 g/kg]; p < 0.01) and blood volume (60 ml/kg [54, 64 ml/kg] vs. 71 ml/kg [65, 78 ml/kg]; p < 0.01) were smaller in patients than in controls. Exercise training increased left ventricular mass and blood volume by approximately 12% and approximately 7% and decreased upright heart rate by 9 beats/min [1, 17 beats/min]. Ten of 19 patients no longer met POTS criteria after training, whereas patient quality of life assessed by the 36-item Short-Form Health Survey was improved in all patients after training. Conclusions: Autonomic function was intact in POTS patients. The marked tachycardia during orthostasis was attributable to a small heart coupled with reduced blood volume. Exercise training improved or even cured this syndrome in most patients. It seems reasonable to offer POTS a new name based on its underlying pathophysiology, the “Grinch syndrome,” because in this famous children''s book by Dr. Seuss, the main character had a heart that was “two sizes too small.” [Copyright &y& Elsevier]

Abstract: Batch reactor experiments were conducted to assess perthitic alkali-feldspar dissolution and secondary mineral formation in an initially acidic fluid (pH=3.1) at 200 °C and 300 bars. Temporal evolution of fluid chemistry was monitored by major element analysis of in situ fluid samples. Solid reaction products were retrieved from two identical experiments terminated after 5 and 78 days. Scanning electron microscopy revealed dissolution features and significant secondary mineral coverage on feldspar surfaces. Boehmite and kaolinite were identified as secondary minerals by X-ray diffraction and transmission electron microscopy. X-ray photoelectron spectroscopy analysis of alkali-feldspar surfaces before and after reaction showed a trend of increasing Al/Si ratios and decreasing K/Al ratios with reaction progress, consistent with the formation of boehmite and kaolinite. Saturation indices of feldspars and secondary minerals suggest that albite dissolution occurred throughout the experiments, while K-feldspar exceeded saturation after 216 h of reaction. Reactions proceeded slowly and full equilibrium was not achieved, the relatively high temperature of the experiments notwithstanding. Thus, time series observations indicate continuous supersaturation with respect to boehmite and kaolinite, although the extent of this decreased with reaction progress as the driving force for albite dissolution decreased. The first experimental evidence of metastable co-existence of boehmite, kaolinite and alkali feldspar in the feldspar hydrolysis system is consistent with theoretical models of mineral dissolution/precipitation kinetics where the ratio of the secondary mineral precipitation rate constant to the rate constant of feldspar dissolution is well below unity. This has important implications for modeling the time-dependent evolution of feldspar dissolution and secondary mineral formation in natural systems. [Copyright &y& Elsevier]

Abstract: A novel hyperbranched polymer endcapped with 4-methylcoumarin group (MCTH40) was prepared via thiol–ene addition reaction of thiol-modified hyperbranched polyester (fully thioglycolic acetate of Boltorn™ H40, TAH40) with a vinyl monomer (7-(4-vinyl-benzyloxyl)-4-methylcoumarin, VBMC), and characterized with 1H NMR and FT-IR spectroscopies. Its reversible photo-crosslinking/photo-cleavage behavior was evaluated based on the UV–vis spectroscopic analysis, and compared with the linear polymer, poly(7-(4-vinyl-benzyloxyl)-4-methylcoumarin (PVBMC)). The absorbance at 319nm in the UV–vis spectrum gradually decreased under UVA irradiation (λ max =365nm), and then rapidly recovered under UVC irradiation (λ max =254nm). The fluorescence intensity of MCTH40 (λ max =469nm) recovered to 85.2% of original level after photo-cleavage under UVC irradiation, higher than 83.5% of PVBMC (λ max =472nm). The UV–vis analysis results indicated that MCTH40 performs more rapid photo-response than linear PVBMC under the same conditions. Furthermore, the average doses of UVA irradiation for the maximum degree of photo-crosslinking were 22.08Jcm−2 for MCTH40 and 28.29Jcm−2 for PVBMC. The average UVC doses of complete photo-cleavage were 9.44Jcm−2 for MCTH40 and 9.58Jcm−2 for PVBMC. The GPC analysis indicated that the average molecular weight and its PDI of MCTH40 showed a slight increase after three reversible cycles. [Copyright &y& Elsevier]

Abstract: This report presents PRImer Selector (PRISE), a new software package that implements several features that improve and streamline the design of sequence-selective PCR primers. The PRISE design process involves two main steps. In the first step, target and non-target DNA sequences are identified. In the second step, primers are designed to amplify target (but not non-target) sequences. One important feature of PRISE is that it automates the task of placing primer–template mismatches at the 3'' end of the primers — a property that is crucial for sequence selectivity. Once a list of candidate primers has been produced, sorting tools in PRISE speed up the selection process by allowing a user to sort the primers by properties such as amplicon length, GC content and sequence selectivity. PRISE can be used to design primers with a range of specificities, targeting individual sequences as well as diverse assemblages of genes. PRISE also allows user-defined primers to be analyzed, enabling their properties to be examined in relation to target and non-target sequences. The utility of PRISE was demonstrated by using it to design sequence-selective PCR primers for an rRNA gene from the fungus Pochonia chlamydosporia. [Copyright &y& Elsevier]

Abstract: To understand reaction pathways and isotope systematics during mineral-catalyzed abiotic synthesis of hydrocarbons under hydrothermal conditions, experiments involving magnetite and CO2 and H2-bearing aqueous fluids were conducted at 400°C and 500 bars. A robust technique for sample storage and transfer from experimental apparatus to stable isotope mass spectrometer provides a methodology for integration of both carbon and hydrogen isotope characterization of reactants and products generated during abiogenic synthesis experiments. Experiments were performed with and without pretreatment of magnetite to remove background carbon associated with the mineral catalyst. Prior to experiments, the abundance and carbon isotope composition of all carbon-bearing components were determined. Time-series samples of the fluid from all experiments indicated significant concentrations of dissolved CO and C1–C3 hydrocarbons and relatively large changes in dissolved CO2 and H2 concentrations, consistent with formation of additional hydrocarbon components beyond C3. The existence of relatively high dissolved alkanes in the experiment involving non-pretreated magnetite in particular, suggests a complex catalytic process, likely involving reinforcing effects of mineral-derived carbon with newly synthesized hydrocarbons at the magnetite surface. Similar reactions may be important mechanisms for carbon reduction in chemically complex natural hydrothermal systems. In spite of evidence supporting abiotic hydrocarbon formation in all experiments, an “isotopic reversal” trend was not observed for 13C values of dissolved alkanes with increasing carbon number. This may relate to the specific mechanism of carbon reduction and hydrocarbon chain growth under hydrothermal conditions at elevated temperatures and pressures. Over time, significant 13C depletion in CH4 suggests either depolymerization reactions occurring in addition to synthesis, or reactions between the C1–C3 hydrocarbons and carbon species absorbed on mineral surfaces and in solution. [Copyright &y& Elsevier]

Abstract: This paper is concerned with the effects of adding tin and/or titanium dopant to sodium aluminium hydride for both dehydrogenation and re-hydrogenation reactions during their reversible storage of molecular hydrogen. Temperature programmed decomposition (TPD) measurements show that the dehydrogenation kinetics of NaAlH4 are significantly enhanced upon doping the material with 2mol% of tributyltin hydride, Sn(Bu)3H but the tin catalyst dopant is shown to be inferior than titanium. On the other hand, in this preliminary work, a significant synergetic catalytic effect is clearly revealed in material co-doped with both titanium and tin catalysts which shows the highest reversible rates of dehydrogenation and re-hydrogenation (after their hydrogen depletion). The re-hydrogenation rates of depleted Sn/Ti/NaAlH4 evaluated at both 9.5 and 140bars hydrogen are also found to be favourable compared to the Ti/NaAlH4, which clearly suggest the importance of the catalyst choice. Basing on these results some mechanistic insights for the catalytic reversible dehydrogenation and re-hydrogenation processes of Sn/Ti/NaAlH4 are therefore made. [Copyright &y& Elsevier]

Abstract: We report here on the high activity and stability of low-content gold–cerium oxide catalysts for the water–gas shift reaction (WGS). These catalysts are reversible in cyclic reduction–oxidation treatment up to 400°C, are non-pyrophoric, and are thus potential candidates for application to hydrogen generation for fuel cell power production. Low-content (0.2–0.9at.%) gold–ceria samples were prepared by single-pot synthesis by the urea gelation/coprecipitation method; and by sodium cyanide leaching of high-content (2–8at.%) gold–ceria materials prepared by various techniques. The low-content gold–ceria catalysts are free of metallic gold nanoparticles. Gold is present in oxidized form, as verified by a variety of analytical techniques. However, these materials display the same WGS activity as the high-content gold ones, and remain free of gold nanoparticles after use in a reaction gas stream composed of 11% CO–26% H2O–26% H2–7% CO2–balance He up to 300°C. We show that the determining factor for the retention of active gold in ceria is the surface properties of the latter. Measurements of lattice constant expansion indicate gold ion substitution in the ceria lattice. The turnover frequency of WGS under the assumption of fully dispersed gold is the same for a variety of low-content gold–ceria preparations. The stability of gold–ceria in various gas compositions and temperatures was good. The most serious stability issue is formation of cerium hydroxycarbonate in shutdown operation. [Copyright &y& Elsevier]

We investigated C-fiber discharges and cerebral potentials evoked by weak CO2 laser beams applied to a tiny skin area in five healthy subjects. Microneurography was performed from the peroneal nerve in the right popliteal area. Cerebral potentials were recorded from the Cz electrode referred to linked earlobes. The mean conduction velocity of five stable single units was 1.1±0.3 m/s. The mean latency of the positive peak of cerebral potentials was 1327.4±46.2 ms. These findings indicated that this new stimulation method selectively activated C-fiber nociceptors of the skin. [Copyright &y& Elsevier]

Nanostructured Au–ceria is a promising new catalyst for low-temperature water-gas shift (LTS). Preparation, characterization, and catalytic properties of this material are reported in this paper. Gold–ceria was prepared by deposition–precipitation (DP), coprecipitation (CP), and gelation methods. The gold loading was varied between 1 and 8.3 at.%, while lanthanum used as a dopant in ceria, was 4 or 10 at.%. Most gold is in metallic state, but ionic gold was also present as identified by XPS. The average ceria crystallite size in samples prepared by gelation was 4.5 and 7 nm, respectively, after calcination at 400 or 650 °C. The gold particle size in samples prepared by DP was <5 nm after 10 h long heating in air at 400 °C. The gold particle size did not increase with gold loading in these samples. A dramatic effect of gold on the reducibility of the surface oxygen of ceria was found by H2-temperature-programmed reduction (TPR). All of the available surface oxygen was reduced, while there was no effect on the bulk oxygen of ceria. The enhancement of cerium oxide reducibility by gold is independent of the method of catalyst preparation. Oxygen storage capacity (OSC) measurements using step pulses of CO were in agreement with the TPR results; the presence of gold greatly enhances the OSC of ceria. Similar tests with copper-containing ceria were conduced for comparison. Carbon-containing species left on the surface after the CO step, can be fully removed with O2 or partially removed with H2O. The high catalytic activity of Au–ceria for LTS reaction correlates well with the ceria structure and oxygen transfer properties. [Copyright &y& Elsevier]

Bulk Cr 1- x Mn x O 2 samples are prepared by high pressure synthesis technology. The crystal structure, magnetic properties and electronic structure of the samples are investigated by experiments and theoretical calculation. The crystal structure of the samples are indexed to a rutile structure with space group P 4 2 / mnm. The lattice parameter a of the samples remains basically unchanged in accordance with Vegard's law, but the lattice parameter c decreases due to increasing Mn dopant content (x) as well as strong Metal–Metal bonding along the c -axis. The saturation magnetization of the Cr 1- x Mn x O 2 samples decreases with an increase in x. According to XPS analysis, there is electron transfer between Mn and Cr in Cr 1- x Mn x O 2. Mn exists as Mn2+ and Mn3+ions, and part of Cr is oxidized to Cr6+. Based on the XPS analysis, the magnetic moment of Cr 1- x Mn x O 2 is calculated and its value is in accordance with the experimental data. [ABSTRACT FROM AUTHOR]

The effect of NRB on the corrosion behavior of X80 pipeline steel in the soil extract solution of Shenyang was studied using polarization curve, electrochemical impedance spectroscopy, weight-loss tests and scanning electron microscope. The results show that NRB accelerates the corrosion rate of steel and promotes the formation of pitting holes on the surface of steel. XPS results show that the types of corrosion products are unchanged. Moreover, electrochemical measurements can effectively evaluate the corrosion behavior of pipeline steel affected by NRB in real time. The data in this work support that NRB can be responsible for pipeline perforation and leakage. • Corrosion of X80 pipeline steel by nitrate reducing bacteria was investigated. • Nitrate reducing bacteria (NRB) accelerates the corrosion of X80 pipeline steel in the soil solution. • NRB can obtain electrons continuously from the surface of steel to accelerate corrosion. • Electrochemical measurements can effectively evaluate the corrosion behavior of NRB. [ABSTRACT FROM AUTHOR]

Magnetic nanocomposite material has undergone significant development in the past few years. However, it is inevitable to initiate mechanical damage during service. Herein, we developed a self-healing magnetic nanocomposite material composed of Fe 3 O 4 nanoparticle and disulfide-based epoxy resin with N , N -dimethylbenzylamine (BDMA) as catalyst. Owing to the catalytic effect of BDMA, the polymer network of the material is successfully formed via thiol-epoxy click reaction of pentaerythritol glycidyl ether (PTEGE) and polydisulfide dithiol (PSDT). More strikingly, BDMA could also catalyze the metathesis reaction of aliphatic disulfide bond and the magnetic nanocomposite material shows more than 60% self-healing efficiency at room temperature for 24 h. The self-healing performance of the magnetic nanocomposite material is investigated and the possible mechanism of disulfide metathesis catalyzed by BDMA is proposed. Besides, with the incorporation of 3 wt% Fe 3 O 4 nanoparticle, the mechanical strength and saturation magnetic induction of the magnetic nanocomposite material are up to 0.31 MPa and 0.51 emu/g, respectively. These results demonstrate that the as-prepared magnetic nanocomposite material has excellent comprehensive performance and can be used for the next generation magnetic material. Unlabelled Image • PSEN exhibit good self-healing performance at room temperature. • TBDMA acts as a double catalyst which can catalyze the thiol-epoxy reaction. [ABSTRACT FROM AUTHOR]

Phosphoglycerate kinase 1 (PGK1) is the first critical enzyme to produce ATP in the glycolytic pathway. PGK1 is not only a metabolic enzyme but also a protein kinase, which mediates the tumor growth, migration and invasion through phosphorylation some important substrates. Moreover, PGK1 is associated with poor treatment and prognosis of cancers. This manuscript reviews the structure, functions, post-translational modifications (PTMs) of PGK1 and its relationship with tumors, which demonstrates that PGK1 has indispensable value in the tumor progression. The current review highlights the important role of PGK1 in anticancer treatments. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy characterized by a complex tumor microenvironment. Angiogenesis is of paramount importance in the proliferation and metastasis of PDAC. However, currently, there are no well-defined biomarkers available to guide the prognosis and treatment of PDAC. In this study, we investigated the interactions between tumor-associated endothelial cells (TAECs) and tumor cells in PDAC, and identified a specific subset of TAECs characterized by high expression of COL4A1. COL4A1+ endothelial cells interact with tumor cells through the COLLAGEN signaling pathway to promote tumor cell proliferation, migration, and invasion. We also observed activation of HOXD9 in COL4A1+ endothelial cells. Based on these findings, we developed a prognostic model called TaEMS, which accurately predicts patient prognosis. TaEMS identified high-risk patients enriched in cell cycle-related pathways and low-risk patients enriched in focal adhesions, smooth muscle regulation, and immune pathways. Moreover, high-risk patients displayed a reduced level of immune cell infiltration, indicating the presence of a "cold tumor" phenotype. Overall, our study uncovered an intricate crosstalk between TAECs and tumor cells in PDAC, emphasizing the role of HOXD9 and highlighting the potential of TaEMS as a prognostic biomarker for precise therapies. • COL4A1+ endothelial cells displayed a close association with tumor cells and protumor cells. • COL4A1+ endothelial cells regulate tumor cell proliferation, migration, and invasion. • The prognostic model, TaEMS, accurately predicts patient prognosis and response to anti-angiogenic therapy. [ABSTRACT FROM AUTHOR]

As the typical multifunctional materials, multinary metal chalcogenides have attracted tremendous attention due to their broad applications. In this work, quinary chalcogenide CuNi x Zn 2− x InS 4 (x = 0–2) nanocrystals with a wurtzite structure have been successfully synthesized for the first time by a solution method. The phase structure analysis suggests that the fabricated wurtzite phase has a disordered structure in which all metal cations share the same position and have a random distribution in the unit cell. The transmission electron microscopy results reveal that the products show a morphological evolution from sphere-like nanocrystals of CuZn 2 InS 4 (x = 0) to bullet-like nanocrystals of CuNi 2 InS 4 (x = 2) together with a growing particle size. All the as-obtained wurtzite CuNi x Zn 2− x InS 4 nanocrystals show a strong and broad visible light absorption. More importantly, the band gap energy of these nanocrystals can be readily tuned from 2.20 eV to 1.44 eV by varying the value of x from 0 to 2, which decreases almost linearly with the composition x. This work demonstrates a new series of I–II 2 –III–VI 4 group chalcogenide semiconductors. Wurtzite structured CuNi x Zn 2− x InS 4 (0 ≤ x ≤ 2) nanocrystals are successfully prepared with tunable band gap for the first time. Image 1 • The quinary alloyed CuNi x Zn 2− x InS 4 nanocrystals are synthesized for the first time. • The obtained CuNi x Zn 2− x InS 4 samples have a cation-disordered wurtzite structure. • The CuNi x Zn 2− x InS 4 nanocrystals exhibit a broad and strong visible light absorption. • The CuNi x Zn 2− x InS 4 nanocrystals show a linear decrease in band gap with increasing x. [ABSTRACT FROM AUTHOR]

To explore anti-wear characteristics for valve pair, the influences of smooth and non-smooth surfaces on tribological properties of the carbon-fiber-reinforced polyetheretherketone (CFRPEEK) coupled with stainless steel 316L were investigated under natural seawater lubrication. The results show that the specimen with ellipsoidal pits has the best frictional performance, followed by the specimen with triangular pits, and the specimen with hemispherical pits is the worst. Microscope observation analysis showed that the reasonable non-smooth surface can reduce adhesion wear and improved the stability of friction system as compared to smooth surface. Results also indicated that the reasonable non-smooth unit can effectively store seawater and debris, and produce hydrodynamic lubrication effect, which surface shows the excellent tribological properties. In this paper, to explore the tribological characteristics of the end-face valve pair of seawater hydraulic motor, different types of bionic non-smooth macro units were processed on the surface of CFR/PEEK specimens using CNC machine tool and the friction pair was formed after coupling with another surface of 316L stainless steel. To study the friction and wear properties of bionic non-smooth surfaces with different morphologies under seawater lubrication, the relative rotating process of valve pairs in seawater was simulated by MMD-5A end-face wear tester, and the three-dimensional topography and roughness of all specimens before and after the experiment were observed by optical three-dimensional surface measuring instrument. Finally, some results were obtained and discussed.Fig.1. Schematic diagram of MMD-5A friction and wear tester and installation drawing of ring-on-disc tester. Image 1 • The effect of surface texture with different shapes and geometries on tribological characteristics under seawater lubrication was analyzed. • The friction and wear properties of bionic non-smooth surfaces with different morphologies were investigated. • The three-dimensional topography and roughness of all samples were observed by surface measuring instrument. • The specimen with ellipsoidal pits has the lowest friction coefficient and the best anti-wear effect. [ABSTRACT FROM AUTHOR]

Dynamic combinatorial chemistry (DCC) involves reversible reactions which can be controlled by thermodynamics method. Transesterification is one of the most widely explored DCC reactions. In this paper, transesterification was used to synthesize self-healing network. First, a three-arm star -shaped hydroxyl-terminated polyglycolide (HTPG) was fabricated though the ring-opening polymerization (ROP) of glycolide by using triethanolamine (TEA) as initiator and tetrabutyl titanate (TBT) as catalyst. Then the self-healing network i.e. isocyanate-based crosslinked star -shaped polyglycolide (ICSPG) was prepared through the crosslink between hexamethylene diisocyanate trimer (HDIT) and HTPG. In order to explore the mechanism of the self-healing, a polyurethane based on a tri-functional polyether polyol (PPPU)was synthesized. The structures of HTPG, ICSPG and PPPU were characterized by fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (1H NMR). The mechanical properties and self-healing properties were characterized by dynamic mechanical thermal analysis (DMTA) and polarizing optical microscopy (POM). And the welding test was used to further characterize the self-healing properties of ICSPG. It was found that mechanical recovery is about 70%. The POM results showed that ICSPG exhibited self-healing properties at high temperature. [ABSTRACT FROM AUTHOR]