Local Application of Tanshinone IIA protects mesenchymal stem cells from apoptosis and promotes fracture healing in ovariectomized mice.

BACKGROUND: Elderly patients suffering from osteoporotic fractures are more susceptible to delayed union or nonunion, and their bodies then are in a state of low-grade chronic inflammation with decreased antioxidant capacity. Tanshinone IIA is widely used in treating cardiovascular and cerebrovascular diseases in China and has anti-inflammatory and antioxidant effects. We aimed to observe the antioxidant effects of Tanshinone IIA on mesenchymal stem cells (MSCs), which play important roles in bone repair, and the effects of local application of Tanshinone IIA using an injectable biodegradable hydrogel on osteoporotic fracture healing. METHODS: MSCs were pretreated with or without different concentrations of Tanshinone IIA followed by H2O2 treatment. Ovariectomized (OVX) C57BL/6 mice received a mid-shaft transverse osteotomy fracture on the left tibia, and Tanshinone IIA was applied to the fracture site using an injectable hydrogel. RESULTS: Tanshinone IIA pretreatment promoted the expression of nuclear factor erythroid 2-related factor 2 and antioxidant enzymes, and inhibited H2O2-induced reactive oxygen species accumulation in MSCs. Furthermore, Tanshinone IIA reversed H2O2-induced apoptosis and decrease in osteogenic differentiation in MSCs. After 4 weeks of treatment with Tanshinone IIA in OVX mice, the bone mineral density of the callus was significantly increased and the biomechanical properties of the healed tibias were improved. Cell apoptosis was decreased and Nrf2 expression was increased in the early stage of callus formation. CONCLUSIONS: Taken together, these results indicate that Tanshinone IIA can activate antioxidant enzymes to protect MSCs from H2O2-induced cell apoptosis and osteogenic differentiation inhibition. Local application of Tanshinone IIA accelerates fracture healing in ovariectomized mice.

Continuous wave cavity ringdown spectroscopy incorporating with an off-axis arrangement, white noise perturbation, and optical re-injection.

We present an ultra-sensitive continuous wave cavity ringdown spectroscopy (cw-CRDS) spectrometer to record high resolution spectra of reactive radicals and ions in a pulsed supersonic plasma. The spectrometer employs a home-made external cavity diode laser as the tunable light source, with its wavelength modulated by radio-frequency white noise. The ringdown cavity with a finesse of ∼105 is arranged with an off-axis alignment. The combination of the off-axis cavity and the white-noise perturbed laser yields quasi-continuum laser-cavity coupling without the need of mode matching. The cavity is further incorporated with an extra multi-pass cavity for optical re-injection of light reflected off the master cavity, which significantly increases the throughput power of the high-finesse cavity. A fast switchable semiconductor optical amplifier is used to modulate the cw laser beam to square wave pulses and to initialize timing controlled ringdown events, which are synchronized to the plasma pulses with an accuracy of ∼3 µs. The performance and potential of the cw-CRDS spectrometer are illustrated and discussed, based on the high resolution near-infrared spectroscopic detection of trace 13C13C radicals generated in a pulsed supersonic C2H2/Ar plasma with a pulse duration of ∼50 µs.

Characterizing VOCs emissions of coal chemical enterprise in China: a case study in five coal chemical enterprises.

Coal chemical-induced climate change has become a global concern. However, the dearth of comprehensive case studies and fundamental data has obstructed the accurate quantification of volatile organic compounds (VOCs) emissions. This has failed to equip coal chemical industries with the necessary guidelines to implement effective emission reduction strategies. In response to this, the present study meticulously examined and contrasted the VOCs emissions from five distinct coal chemical enterprises in China. This was achieved through the application of life cycle assessment (LCA), a tool used to discern the primary factors influencing VOCs emissions and to identify potential avenues for VOCs emissions reduction. The analysis revealed that BT exhibited the highest emission intensity (5.58E-04 tons/ton), followed by ED (4.89E-04 tons/ton), YL (4.23E-04 tons/ton), XJ (2.94E-04 tons/ton), and SM (1.74E-04 tons/ton). Among these enterprises, coal-to-olefins enterprises predominantly discharged VOCs via sewage treatment (average 69.12%), while coal-to-methanol enterprises primarily emitted VOCs during circulating water cooling (40.02%). In coal-to-oil enterprises, storage and blending emerged as the principal source of VOCs emissions (56.83%). As a result, this study advocates that coal chemical enterprises concentrate on curbing VOCs emissions from highly concentrated wastewater, regulating the concentration of purgeable organic carbon in circulating water cooling systems, and instituting effective treatment methods for methanol storage tank emissions. These findings proffer invaluable insights for devising VOCs control measures in regions affected by intensive coal chemical production.

A BaGa4Se7 crystal based pulsed mid-infrared light source with a narrow linewidth in 4-12 µm.

We present a BaGa4Se7 (BGSe) crystal based coherent pulsed light source for high resolution mid-infrared (MIR) spectroscopy in the 4-12 µm region. The all-solid-state system consists of an injection seeded optical parametric generator (OPG) and an optical parametric amplifier (OPA) using two KTiOPO4 crystals. The idler output of OPG-OPA and the fundamental output (1064 nm) of a wavelength stabilized Nd:YAG laser are employed for difference frequency generation of MIR pulses in the BGSe crystal. Pulsed MIR radiation in the 4-12 µm range is obtained with typical pulse energies higher than 100 µJ and pulse durations of ∼5 ns. By measuring H2O absorption lines in the 8 µm region with this MIR light source and a cavity ring-down spectrometer, the linewidth of the MIR source is inferred as 120 ± 10 MHz, which is very close to the Fourier-transform limited linewidth of 5 ns laser pulses.

Photoelectron Spectroscopy Confirms the Gas-Phase Stability of the C3O2- Anion.

The carbon suboxide anion with an asymmetric zigzag structure, C3O2-, which was recently characterized in a solid neon matrix, has not been observed in the gas phase. Here, we have experimentally generated C3O2- in a supersonic plasma jet expansion and studied it by negative ion photoelectron spectroscopy. A spectral analysis based on the calculated Franck-Condon factors, in combination with quantum chemical calculations, has for the first time yielded a determination of the electron affinity of the neutral carbon suboxide, EA = +0.48(8) eV. Molecular orbital (MO) analysis indicates that, upon linear-to-zigzag geometric change, additional σ-π MO mixing significantly reduces the energy of the singly occupied MO of C3O2- and thus stabilizes the negative ion in the gas phase. This work provides a benchmark understanding of the gas-phase stability of the C3O2- anion.

Prediction of control temperature and emergency temperature of monadic/binary aromatic nitro compounds by quantitative structure-property relationship: correlation study of self-accelerating decomposition temperature in thermal hazard assessment.

CONTEXT: The thermal hazard of reactions caused by the structural instability of aromatic nitro compounds is a major concern in the field of chemical process safety and one of the main causes of major thermal runaway (TR) accidents such as fire and explosion. Among them, the self-accelerating decomposition temperature (SADT), as an important parameter, has been widely used to evaluate the thermal hazards of aromatic nitro compounds in actual storage and transportation processes. However, the control temperature (CT) and emergency temperature (ET), which depend on and are associated with SADT, have been rarely reported in previous studies. In this work, multiple linear regression (MLR) and artificial neural network (ANN) models for CT and ET were constructed based on the molecular descriptors corresponding to the stable structures of 27 monadic/binary aromatic nitro compounds, combined with advanced adiabatic accelerating calorimetric experiments and quantitative structure-property relationship (QSPR). The optimal subset of descriptors with significant contributions was screened out while the fit, predictive ability, and robustness of the four types of models were evaluated with internal and external validation parameters, and finally, two types of parameters (R2 and ARE) were selected as the main indicators for a comprehensive comparative analysis. The results show that the four models fit the experimental data well. During this period, the accuracy of ANN models is slightly higher than that of MLR models, and the QSPR models under the two modes (linear and nonlinear) are more inclined toward ET in prediction ability. Based on simplifying the calculation process and realizing rapid parameter prediction, this study is expected to provide technical support for engineering applications such as safe operation, safe storage and transportation of substances, and emergency response in the chemical industry. METHODS: In this work, we tested and calculated the thermal safety parameters of 27 monadic/binary aromatic nitro compounds by ARC and AKTS and further used the PubChem database and Gaussian 09 software program to obtain and optimize their corresponding molecular structures. The geometric optimization process adopts DFT on the B3LYP level and the 6-31 + G(d, p) basis set, while the same functional and basis set was used for vibration analysis. The OpenBabel toolbox and ChemDES platform were used for transformation coding and descriptor calculation. Finally, IBM SPSS Statistics 24 and MATLAB software were used to construct MLR models and ANN models, respectively.

Monotropein Protects Mesenchymal Stem Cells from Lipopolysaccharide-Induced Impairments and Promotes Fracture Healing in an Ovariectomized Mouse Model.

Monotropein is one of the active ingredients in Morinda Officinalis, which has been used for the treatment in multiple bone and joint diseases. This study aimed to observe the in vitro effects of Monotropein on osteogenic differentiation of lipopolysaccharide treated bone marrow mesenchymal stem cells (bMSCs), and the in vivo effects of local application of Monotropein on bone fracture healing in ovariectomized mice. Lipopolysaccharide was used to set up the inflammatory model in bMSCs, which were treated by Monotropein. Molecular docking analysis was performed to evaluate the potential interaction between Monotropein and p65. Transverse fractures of middle tibias were established in ovariectomized mice, and Monotropein was locally applied to the fracture site using injectable hydrogel. Monotropein enhanced the ability of primary bMSCs in chondro-osteogenic differentiation. Furthermore, Monotropein rescued lipopolysaccharide-induced osteogenic differentiation impairment and inhibited lipopolysaccharide-induced p65 phosphorylation in primary bMSCs. Docking analysis showed that the binding activity of Monotropein and p65/14-3-3 complex is stronger than the selective inhibitor of NF-κB (p65), DP-005. Local application of Monotropein partially rescued the decreased bone mass and biomechanical properties of callus or healed tibias in ovariectomized mice. The expressions of Runx2, Osterix and Collagen I in the 2-week callus were partially restored in Monotropein-treated ovariectomized mice. Taking together, local application of Monotropein promoted fracture healing in ovariectomized mice. Inhibition of p65 phosphorylation and enhancement in osteogenesis of mesenchymal stem cells could be partial of the effective mechanisms.

Photodissociation Dynamics of the [O2-H2O]+ Ionic Complex.

We present an experimental study on the photodissociation dynamics of [O2-H2O]+ in the 580-266 nm wavelength range using a cryogenic ion trap velocity map imaging spectrometer. The cryogenic ion trap produces mass selected and internally cold [O2-H2O]+ ions for photodissociation. By detecting both the O2+ and H2O+ photofragments using the time-of-flight mass spectrometry and velocity map imaging techniques, branching ratios and total kinetic energy release distributions of the O2+ + H2O and H2O+ + O2 product channels are experimentally measured at 16 different excitation energies. State-resolved photodissociation mechanisms of the parent [O2-H2O]+ are interpreted as (1) the O2(X3Σg-) + H2O+(X~2B1), O2(a1Δg) + H2O+(X~2B1), and O2(X3Σg-) + H2O+(A~2A1) channels are produced from direct dissociation of [O2-H2O]+ in its excited B~2A″, D~2A″, and F~2A″ states, respectively; (2) the O2+(X2Πg) + H2O(X~A11) channel is produced from nonadiabatic relaxations of the excited B~2A″, D~2A″, and F~2A″ states to the X~2A″ ground state with subsequent dissociation. The latter nonadiabatic processes involve charge-transfer on the potential energy surfaces, and the charge-transfer probabilities are determined from experimental results. The dissociation energy of the ground state to the lowest dissociation limit is experimentally refined as D0 = 1.05 ± 0.05 eV. This work provides important information to understand the charge-transfer dynamics in the photochemistry of [O2-H2O]+ and in the ion-molecule reaction O2 + H2O+ → O2+ + H2O.

Transient change in the binocular visual function after femtosecond laser-assisted in situ keratomileusis for myopia patients.

Purpose: The goal of this study was to compare the difference in binocular visual function for high and low-moderate myopes before and after femtosecond laser-assisted in situ keratomileusis (FS-LASIK). Methods: Thirty-three subjects (17 males and 16 females) were divided into two groups according to their preoperative refractive errors in spherical equivalent (SE): low-moderate myopia group (SE ≥-6.00 D) and high myopia group (SE <-6.00 D). The binocular visual function including accommodative amplitude (AA), accommodative facility (AF), positive and negative relative accommodation (PRA and NRA, respectively), horizontal phoria measurement, positive and negative fusion vergence, accommodative-convergence over accommodation (AC/A) ratio, and stereopsis were assessed with the best-corrected vision before patients received FS-LASIK and 7 and 30 days after the surgery. Repeated measures analysis of variance (ANOVA) was applied to study the change in binocular visual function. Results: The AF values in both groups were significantly reduced after 7 days of FS-LASIK (baseline vs. day 7 (mean): high myopia group: 7.85 vs. 5.62 cpm, repeated ANOVA, P = 0.01; low-moderate myopia group: 5.95 vs. 4.40 cpm, repeated ANOVA, P = 0.04). This change returned to the baseline level 30 days after the operation. In addition, the horizontal phoria values in both groups were significantly reduced for both distant (P = 0.019 and P = 0.001, respectively) and near (P = 0.003 and P = 0.049, respectively) 7 days after the operation, but they rebound to preoperative state after 30 days. Conclusion: A transient change in binocular visual function was noticed after 7 days of FS-LASIK operation, which could cause symptoms of asthenopia. Our data showed all the binocular visual functions returned to baseline level after 30 days of operation.

A real-time phase processing system for phase sensitive optical time domain reflectometer.

In order to improve the real-time performance of a phase-sensitive optical-time-domain reflectometer (Φ-OTDR), a fully digital phase processing system is demonstrated. Using digital down-conversion and field programmable gate array (FPGA) hardware calculation, the phase of the Rayleigh scattering light can be demodulated in real-time. Benefiting from the pipeline calculation in the FPGA, the real-time performance of this system is not affected by the interrogation rate and fiber sensing distance. Experiments show that this real-time detection system has the same vibration detection performance as an offline data process and has good stability. The dynamic strain sensing with a sensing distance of 50 km, an interrogation rate of 1 kHz, and a spatial sampling interval of 1 m is experimentally demonstrated. The obtained results indicate that the fully digital signal processing system can ensure the real-time detection of Φ-OTDR under the condition of long distance and high resolution.

High-Resolution Electronic Spectrum of the 1,4,6-Heptatrienyl Radical in the Gas Phase.

We report the gas-phase identification of the 1,4,6-heptatrienyl (C7H9) radical via its A~2B1-X~2A2 electronic transition spectrum. The optical absorption spectrum in the 590-630 nm region is recorded using cavity ring-down spectroscopy in combination with a supersonic plasma jet. An analysis of the rotationally resolved 000 origin band spectrum has allowed an accurate determination of spectroscopic constants for both the X~2A2 electronic ground and A~2B1 excited states of this radical. Ab initio calculations at the CASPT2/cc-pVTZ level have been performed to predict the radical structure and molecular constants that are in good agreement with the experimental results. By combination with available experimental data for the allyl and 1,4-pentadienyl radicals, we extrapolate an excitation energy gap between the ground and first excited states of a long C2n-1H2n+1 polyenyl chain converging to a residual energy gap, suggesting the presence of residual nonuniform C-C bond lengths in a long polyenyl chain.

Novel Magnetically Driven Superhydrophobic Sponges Coated with Asphaltene/Kaolin Nanoparticles for Effective Oil Spill Cleanup.

Fast and effective cleanup of oil spills remains a global challenge. A modified commercial sponge with superhydrophobicity, strong absorption capacity, outstanding magnetic response, and fire resistance were fabricated by a facile and inexpensive route of dip-coated melamine sponge carbonization. The low-cost petroleum asphaltene and kaolin nanoparticles were used as the dip-coating reagent. High absorption capacity of the fabricated sponges allowed rapid and continuous removal of oil contaminants. Taking advantage of the good refractory property, the sponges can be used in burning conditions and directly reused after burning out of the absorbed oil. Reusability tests showed that the modified sponges still maintained high absorption capacity (>85%) after six regeneration and reuse cycles. These characteristics make the fabricated sponge a promising aid to promote effective in situ burning cleanup of oil spills, contributing as a magnetic oil collector and a fire-resistant flexible boom. An example usage scenario of the sponges applied to in situ burning cleanup of oil spills is described.

Correction: Runx1 is a central regulator of osteogenesis for bone homeostasis by orchestrating BMP and WNT signaling pathways.

[This corrects the article DOI: 10.1371/journal.pgen.1009233.].

Gas-Phase Optical Spectra of the Indenyl Radical and Its Quantitative Detection in a Jet-Stirred Reactor.

Resonance-stabilized radicals (RSRs), such as the indenyl radical (C9H7), are proposed to be initiator radicals in soot inception and growth in hydrocarbon combustion processes, but spectroscopic data for many RSRs are still lacking. In this work, the gas-phase optical absorption spectra of the B̃2A2-X̃2A2 electronic transition of indenyl were identified in a supersonic indene/argon plasma jet. Spectroscopic parameters, including the transition energy, rotational constants, and upper-state lifetime broadening, were obtained from analysis of the experimental spectra. The results were readily applied to the quantitative detection of indenyl produced from high-temperature reactions in a jet-stirred reactor. This study now makes indenyl optically accessible in further reaction kinetics studies and in situ spectroscopic diagnostics of hydrocarbon combustion processes.

Improving the absorption load, high viscosity, and regeneration efficiency of CO2 capture using a novel tri-solvent biphasic solvents of TETA-AMP-1DMA2P.

Currently, biphasic solvents are receiving more attention for CO2 capture due to their energy-saving potential. Whereas, most of the current biphasic solvents still suffer from high viscosity and low regeneration efficiency. To solve this problem, a novel tri-solvent biphasic solvent triethylenetetramine (TETA)-2-amino-2-methyl-1-propanol (AMP)-1-dimethylamino-2-propanol (1DMA2P) was proposed in this study, and its absorption properties, viscosity changes, desorption properties, recyclability capacity, and reaction mechanism were explored. The results showed that the CO2 absorption load showed a trend of firstly increasing and then decreasing with the increase of AMP concentration. Although the volume of the rich phase increased with increasing AMP concentration after the absorption, it also decreases the viscosity growth. The viscosity of the solution decreased from 498 mPa•s to 91 mPa•s. During the desorption process, the maximal desorption rates of AMP-containing solvents is significantly greater than that of 2 mol/L (M) TETA + 2 M 1DMA2P (2T2D). Simultaneously, the recyclability capacity of the AMP-containing solvents were also significantly higher than that of 2T2D. The regeneration efficiency of 1.5 M TETA + 0.5 M AMP + 2 M 1DMA2P (1.5T0.5A2D) was 81.92%. It was concluded by 13C NMR analysis that amino groups in TETA and AMP can react with CO2 to form carbamates and carbonates. Since AMP in the biphasic solution can generate free protons through various pathways during the desorption process, it promotes the decomposition of TETA-carbamate. This process achieves the deep stripping of CO2 in biphasic solvent. Overall, TETA-AMP-1DMA2P solution is a promising energy-saving candidate for industrial CO2 capture due to its competitive absorption-desorption performance and low viscosity.

Chemical Process Alarm Root Cause Diagnosis Method Based on the Combination of Data-Knowledge-Driven Method and Time Retrospective Reasoning.

Due to the abrupt nature of the chemical process, a large number of alarms are often generated at the same time. As a result of the flood of alarms, it largely hinders the operator from making accurate judgments and correct actions for the root cause of the alarm. The existing diagnosis methods for the root cause of alarms are relatively single, and their ability to accurately find out complex accident chains and assist decision making is weak. This paper introduces a method that integrates the knowledge-driven method and the data-driven method to establish an alarm causal network model and then traces the source to realize the alarm root cause diagnosis, and develops the related system modules. The knowledge-driven method uses the hidden causality in the optimized hazard and operability analysis (HAZOP) report, while the data-driven method combines the autoregressive integrated moving average model (ARIMA) and Granger causality test, and the traceability mechanism uses the time-based retrospective reasoning method. In the case study, the practical application of the method is compared with the experimental application in a real petrochemical plant. The results show that this method helps to improve the accuracy of correct diagnosis of the root cause of the alarm and can assist the operators in decision making. Using this method, the root cause diagnosis of alarm can be realized quickly and scientifically, and the probability of misjudgment by operators can be reduced, which has a certain degree of scientificity.

Quantum Key Distribution over 658 km Fiber with Distributed Vibration Sensing.

Twin-field quantum key distribution (TFQKD) promises ultralong secure key distribution which surpasses the rate distance limit and can reduce the number of the trusted nodes in long-haul quantum network. Tremendous efforts have been made toward implementation of TFQKD, among which, the secure key with finite size analysis can distribute more than 500 km in the lab and in the field. Here, we demonstrate the sending-or-not-sending TFQKD experimentally, achieving a secure key distribution with finite size analysis over a 658 km ultra-low-loss optical fiber. Meanwhile, in a TFQKD system, any phase fluctuation due to temperature variation and ambient variation during the channel must be recorded and compensated, and all this phase information can then be utilized to sense the channel vibration perturbations. With our quantum key distribution system, we recovered the external vibrational perturbations generated by artificial vibroseis on both the quantum and frequency calibration link, and successfully located the perturbation position in the frequency calibration fiber with a resolution better than 1 km. Our results not only set a new distance record of quantum key distribution, but also demonstrate that the redundant information of TFQKD can be used for remote sensing of the channel vibration, which can find applications in earthquake detection and landslide monitoring besides secure communication.

Comparative lifecycle greenhouse gas emissions and their reduction potential for typical petrochemical enterprises in China.

Petrochemical enterprises have become a major source of global greenhouse gas (GHG) emissions. Yet, due to the unavailability of basic data, there is still a lack of case studies to quantify GHG emissions and provide petrochemical enterprises with guidelines for implementing energy conservation and emission reduction strategies. Therefore, this study conducted a life cycle assessment (LCA) analysis to estimate the GHG emissions of four typical petrochemical enterprises in China, using first-hand data, to determine possible emission reduction measures. The analytical data revealed that Dushanzi Petrochemical (DSP) has the highest GHG emission intensity (1.17 tons CO2e/ton), followed by Urumqi Petrochemical (UP) (1.08 tons CO2e/ton), Dalian Petrochemical (DLP) (average 0.58 tons CO2e/ton) and Karamay Petrochemical (KP) (average 0.50 tons CO2e/ton) over the whole life cycle. At the same time, GHG emissions during fossil fuel combustion were the largest contributor to the whole life cycle, accounting for about 77.31%-94.27% of the total emissions. In the fossil-fuel combustion phase, DSP had the highest unit GHG emissions (1.20 tons CO2e), followed by UP (0.89 tons CO2e). In the industrial production phase, DLP had the highest unit GHG emissions (average 0.13 tons CO2e/ton), followed by UP (0.10 tons CO2e/ton). During the torch burning phase, torch burning under accident conditions was the main source of GHG emissions. It is worth noting that the CO2 recovery stage has "negative value," indicating that it will bring some environmental benefits. Further scenario analysis shows that effective policies and advanced technologies can further reduce GHG emissions.

High-resolution laser spectroscopy of the trans- and cis-1-vinylpropargyl radicals.

Rotationally resolved spectra of the Ã2A''-X̃2A'' origin bands for both trans- and cis-conformers of 1-vinylpropargyl radical (1VPR) are experimentally studied. Rotational constants for both ground and electronically excited states are experimentally determined. The stability of the Ã2A'' excited state of the cis-1VPR is found to be higher than that of trans-1VPR, which is likely due to additional π-overlap and increased pπ electron delocalization in the excited state of cis-1VPR.

Synergistic bioreduction of Te(â £) using S(0) as electron donor.

This study for the first time bioreduced Te(IV) using elemental sulfur (S0) as electron donor, achieving 91.17%±0.8% conversion with reaction rate of 0.77 ± 0.01 mg/L/h in a 60-day cultivation. Characterization using X-ray photoelectron spectroscopy and X-ray power diffraction analyses confirmed that most removed Te(IV) was reduced to elemental Te(0) deposits, while ion chromatogram analysis showed that most S(0) was oxidized to sulfite and sulfate. High-throughput 16S rRNA gene sequencing indicated that the Te(IV) reduction coupled to S(0) oxidation was mediated synergistically by a microbial consortia with S(0)-oxidizing bacteria (Thiobacillus) to generate volatile fatty acids as metabolites and Te(IV)-reducing bacteria (Rhodobacter) to consume formed volatile fatty acids to yield Te(0). The synergy between these two strains presents a novel bioremediation consortium to efficiently treat Te(IV) wastewaters.