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Particulate matter has major climate and health impacts, and it is therefore of utmost importance to be able to measure the composition of these particles to gain insights into their sources and characteristics. Many methods, both offline and online, have been employed over the years to achieve this goal. One of the most recent developments is the Vaporization Inlet for Aerosols (VIA) coupled to a nitrate Chemical Ionization Mass Spectrometer (NO3-CIMS), but a thorough understanding of the VIA–NO3-CIMS system remains incomplete. In this work, we ran a series of tests to assess the impacts from different systems and sampling parameters on the detection efficiency of highly oxygenated organic molecules (HOMs) in the VIA–NO3-CIMS. Firstly, we found that the current VIA system (which includes an activated carbon denuder and a vaporization tube) efficiently transmits particles (> 90 % for particles larger than 50 nm), while removing gaseous compounds (> 97 % for tested volatile organic compounds (VOCs)). One of the main differences between the VIA and traditional thermal desorption (TD) techniques is the very short residence time in the heating region, on the order of 0.1 s. We found that this short residence time and the corresponding short contact with heated surfaces, is likely one of the main reasons why relatively reactive or weakly bound, such as peroxides, were observable using the VIA. However, the VIA also requires much higher temperatures to fully evaporate the aerosol components. For example, the evaporation temperature of ammonium sulfate particles using the VIA was found to be about 100–150 °C higher than in typical TD systems. We also observed that the evaporation of particles with larger sizes occurred at slightly higher temperatures compared to smaller particles. Another major aspect that we investigated was the gas-phase wall losses of evaporated molecules. With a more optimized interface between the VIA and the NO3-CIMS, we were able to greatly decrease wall losses and thus improve on the sensitivity compared to our earlier VIA work. This interface included a dedicated sheath flow unit to cool the heated sample and provide the NO3-CIMS with the needed high flow (10 L min-1). Our results indicate that most organic molecules observable by the NO3-CIMS can evaporate and be transported efficiently in the VIA system, but upon contact with the hot walls of the VIA, the molecules are instantaneously lost. This loss potentially leads to fragmentation products that are not observable by the NO3-CIMS. Thermograms, obtained by scanning the VIA temperature, were found to be very valuable for both quantification purposes and estimating the volatility of the evaporating compounds. We developed a simple one-dimensional model to account for the evaporation of particles and the temperature-dependent wall losses of the evaporated molecules, and thereby estimate the concentration of HOMs in SOA particles. Overall, our results provide much-needed insights into the key processes underlying the VIA–NO3-CIMS method. Although there are still some limitations that could be addressed through hardware improvements, the VIA-NO3-CIMS is a very promising and useful system for fast online measurements of HOMs in the particle phase.

Additional file 1: Figure S1. Isolation of exosome-like extracellular vesicles from Catharanthus roseus.C. roseus picked from Guangzhou, China.TEM analysis of C. roseus-derived exosome-like nanovesicles. Scale bar = 100 nm.Particle size distribution of C. roseus-derived exosome-like nanovesicles. Peak 1: 200.80 ± 87.22 nm, with an intensity of 65.0%; Peak 2: 14.65 ± 3.40 nm, with an intensity of 34.0%; Peak 3: 4881.00 ± 682.00 nm, with an intensity of 1.0%.TEM analysis of exosome-like nanovesicles derived from C. roseus leaves, stems, and flowers. Scale bar = 100 nm.Protoplasts that settle at the bottom of the beaker after enzymatic digestion.Pictures of nanovesicles obtained by different ultracentrifugation methods. a. Juicing then differential ultracentrifugation; b. enzyme digestion then differential ultracentrifugation; c. juicing then sucrose cushion ultracentrifugation; d. enzyme digestion then sucrose cushion ultracentrifugation. Figure S2. CLDENs with membrane fusion in an acidic environment.The larger vesicle was fusing with the smaller vesicles.Two vesicles with similar particle sizes were merging. Figure S3. Biodistribution of CLDENs.Biodistribution of CLDENs in the organs after oral administration. a. Fluorescent signals in the brain, heart, liver, spleen, thymus, lung and kidney. b. Fluorescent signals in the gastrointestinal tract. A strong fluorescence signal exceeding the detection threshold of the instrument was observed in the stomach until the 12th hour.Biodistribution of CLDENs in the organs after tail vein injection. a. Fluorescent signals in the brain, heart, liver, spleen, thymus, lung and kidney. b. Fluorescent signals in the gastrointestinal tract. Figure S4. CLDENs were found in the lymph nodes in the neck of animals after intraperitoneal injection. Figure S5. Molecular weights distribution of the identified proteins in the PLANT group. Figure S6. Effects of different treatments on CLDENs’ immunostimulatory activity. CLDENs were treated with proteinase K at 37 °C, RNase A at 37 °C, DNase I at 37 °C, strong acid and strong base at 25 °C, 0.1% Triton X-100 at 25 °C, and 0.1% SDS at 25 °Cfor 30 min or heated at 100 °C for 10 min. Next, CLDENs’ ability to encourage nitric oxide secretion from RAW264.7 cells was investigated. CLDENs’ activity was not significantly altered by proteinase K at 37 °C, RNase at 37 °C, strong acid/strong base at 25 °C, and DNase I at 37 °C treatment, but their immunostimulatory activity was lost by 0.1% Triton X-100 at 25 °C, 0.1% SDS at 25 °C, and 100 °C heating treatment. Data were mean ± SD, n = 3; **P < 0.01 and ***P < 0.001 vs. Blank. ##P < 0.01 and ###P < 0.001 vs. CLDENs group. ns, not significant. Figure S7. Induction of C. roseus cells.Germinating dedifferentiated cells in the leaves of C. roseus.Germinating cambial meristematic cells in the stems of C. roseus.C. roseus dedifferentiated cells viewed through a 20 × optical microscope. Scale bar = 100 μm.C. roseus cambial meristematic cells viewed through a 20 × optical microscope. Scale bar = 100 μm.. Comparison of the yield of three nanovesicles. Data were mean ± SD, n = 3, **P < 0.01 vs. CLDENs group. Table S1. List of identified substances in lipidomic analysis. Table S2. List of identified substances in metabolomic analysis. Table S3. List of disease phenotypes that correlated with CLDENs. Table S4. Proteins significantly up-regulated in differential proteomics. Table S5. Real-time quantitative PCR primer sequence.

This review aims to demonstrate the psychological nursing competencies of nurses and to summarize the assessment methods of competencies.

Contemporary landscape architecture studies have paid close attention to the interactions between public aesthetic preferences and the landscape environment. Scenic beauty has become an important evaluation indicator of landscape quality. The quality of the plant color landscape is an important factor affecting scenic beauty. Exploring the relationship between the composition rules and internal properties of autumn plant color landscapes in urban parks and public aesthetic preferences can provide new ideas for the evaluation and design of plant community color landscapes. Taking 12 parks in Changsha City, Hunan Province, China, as the study area and 85 plant communities as the sample plots, scenic beauty estimation (SBE) was used to evaluate the autumn plant color landscape of urban parks. ColorImpact software was used to extract the color values of each plant community. Fifteen original color element indicators were determined, and the data were statistically analyzed by principal component analysis (PCA), one-way ANOVA, multiple comparison analysis and systematic cluster analysis. Four principal components were extracted to construct the characteristic indices and a comprehensive model of the color landscape quality of autumn plant communities. The four characteristic indices showed significant or extremely significant differences among the five SBE grades. From the overall trend, the SBE grades showed a positive correlation with PC1 (primary and adjunctive color index), PC2 (color structure and property index) and PC3 (autumn-color-leafed index) and a negative correlation with PC4 (intersperse color index). RPH (ratio of primary hue), RP (ratio of primary color), RC (color-leafed index), RWC (ratio of warm and cool colors), and NC (number of colors) were the key factors affecting the SBE grade. Overall, RPH, RP, RC, and RWC positively influenced the SBE values, while NC negatively influenced the SBE values, and five to seven colors were more moderate. The quality of the color landscape can be improved by creating plant communities with three types of color composition: warm-toned dominant type, warm- and cold-toned contrast type, and multicolor harmonic type. The results provide a reference for the evaluation, design and construction of autumn plant color landscapes in urban parks.

ObjectiveThis study aimed to compare the effectiveness and safety of oxcarbazepine (OXC) vs. levetiracetam (LEV) for treating infantile focal epilepsy in a longitudinal cohort study.MethodsWe enrolled 187 consecutive patients aged 2–24 months who received OXC or LEV as initial monotherapy; 161 patients completed the study. The longitudinal analysis involved anti-seizure medication (ASM) responsiveness, safety, the establishment of epilepsy syndrome, and etiology over a median follow-up of 2 years (interquartile range [IQR] 1.6–2.4). The relative efficacy and retention rates of OXC vs. LEV were evaluated using generalized linear regression models and the Cox proportional hazards model.ResultsThe 161 patients who completed the study had comparable baseline demographics and clinical variables between the OXC group (n = 83) and LEV group (n = 78). Overall, the mean age at onset was 6 months (IQR 4.3–9). The most common epilepsy syndrome was self-limited familial/non-familial infantile epilepsy (54.7%). Epilepsy was related to genetic and unknown causes in 34.2 and 52.2% of the patients, respectively. OXC achieved significantly higher responses than LEV for seizure freedom (risk ratio [RR] = 1.71, 95% confidence interval [CI] = 1.28–2.73, P < 0.001) and 12-month retention rate after onset (hazard ratio [HR] = 1.84, 95% CI = 1.15–2.95, P = 0.007). Moreover, OXC showed more obvious effects for patients aged < 1 year diagnosed with self-limited familial/non-familial infantile epilepsy and non-syndromic epilepsy with genetic or unknown causes. The adverse events related to both OXC and LEV were well-tolerated.SignificanceOXC could be an alternative to LEV for treating infantile focal epilepsy. OXC monotherapy can be considered first-line treatment for patients aged

Diterpenes (C20H32) are biogenically emitted volatile compounds that only recently have been observed in ambient air. They are expected to be highly reactive, and their oxidation is likely to form condensable vapors. However, until now, no studies have investigated gas-phase diterpene oxidation. In this paper, we explored the ozonolysis of a diterpene, ent-kaurene, in a simulation chamber. Using state-of-the-art mass spectrometry, we characterized diterpene oxidation products for the first time, and we identified several products with varying oxidation levels, including highly oxygenated organic molecules (HOM), monomers, and dimers. The most abundant monomers measured using a nitrate chemical ionization mass spectrometer were C19H28O8 and C20H30O5, and the most abundant dimers were C38H60O6 and C39H62O6. The exact molar yield of HOM from kaurene ozonolysis was hard to quantify due to uncertainties in both the kaurene and HOM concentrations, but our best estimate was a few percent, which is similar to values reported earlier for many monoterpenes. We also monitored the decrease in the gas-phase oxidation products in response to an increased condensation sink in the chamber to deduce their affinity to condense. The oxygen content was a critical parameter affecting the volatility of products, with four to five O atoms needed for the main monomeric species to condense onto 80g nm particles. Finally, we report on the observed fragmentation and clustering patterns of kaurene in a Vocus proton-transfer-reaction time-of-flight mass spectrometer. Our findings highlight similarities and differences between diterpenes and smaller terpenes during their atmospheric oxidation, but more studies on different diterpenes are needed for a broader view of their role in atmospheric chemistry., This research has been supported by the European Research Council, Framework programme Horizon 2020 (COALA (grant no. 638703)) and the Framework programme FP7 (IMBALANCE-P (grant no. 610028)), the Academy of Finland (grant nos. 317380, 320094, 307797, and 314099), the Fundación Ramón Areces (grant ELEMENTAL-CLIMATE), the China Scholarship Council (grant no. 201906220191), the Spanish government (grant no. PID2019-110521GB-I00) and the Catalan government (grant nos. SGR 2017-1005 and AGAUR-2020PANDE00117).

Additional file 2. Univariate and multivariate regression analysesfor suicidal ideation (SI) in cancer patients (N=560).

Additional file 1. Socio-demographiccharacteristics of training dataset (N=560) and validation dataset (N=260).

In this paper, the hot deformation behavior of Ti22Al25Nb was investigated by hot compression over a range of temperatures (950-1050 °C) and strain rates (0.001-1 s−1). Considering the adiabatic heating and friction, the original curves were corrected. The friction-corrected data were lower than the measured flow stress data. The flow stress data increased after the temperature correction owing to the elimination of the softening effect. In addition, the work hardening effects on the hot deformation of the normal and multi-peak flow stress curves were compared. A critical dislocation density was proposed to analyze the multi-peak phenomenon. When the dislocation density decreased to a critical value, the work hardening and dynamic recrystallization mechanisms reached a balance. Then, a new work hardening mechanism became dominant, and the flow stress increased. The effect of second-phase particles on the hot deformation mechanisms was investigated. The result showed that second-phase particles led to a high nucleation rate and a low growth rate of new recrystallization grains during the rapid hot deformation.

Ti-5331 titanium alloy, a new near α titanium alloy, as a candidate material for pressure hull of fusion reactor was studied in details in this paper. Firstly, the flow behavior was analyzed by stress-strain curves obtained by isothermal compression of Ti-5331 alloy, and the constitutive model was developed in the form of the hyperbolic sine. Secondly, the effects of deformation parameters on spheroidization mechanism were discussed. Finally, based on the dynamic materials model and instability criterion, the power dissipation map and instability map were constructed at the strain of 0.6, the obtained optimal processing parameters of Ti-5331 alloy were 750°C/0.001–0.01 s−1 and 850–900 °C/0.01–0.1 s−1 with the peak efficiencies of 65% and 73% respectively, which were further verified by the plate rolling test of Ti-5331 alloy.

The raw data of effects of three insecticides on the expression of cytochrome P450 CYP6B7 in Helicoverpa armigera

Accurate detection of glucose is essential for the diagnosis of diabetes, wherein effective and sensitive biosensors for glucose detection are needed. Here, we fabricated a glucose sensor based on field-effect transistor (FET) with bimetallic nickel-copper metal-organic frameworks (Ni/Cu-MOFs) as its channel layers which were grown in-situ through a simple one-step hydrothermal method and modified with glucose oxidase (GOD) by using glutaraldehyde (GA) as linkers. Due to the synergistic effect of Ni ions and Cu ions in MOFs, the sensor (GOD-GA-Ni/Cu-MOFs-FET) showed good field effect performance and great responses to glucose through enzymatic reactions. It displayed a piecewise linear relationship in the wide range (1 μM–20 mM), and provided high sensitivity (26.05 μAcm−2mM−1) in the low concentration (1–100 μM) and a low detection limit (0.51 μM). The sensor also had these advantages of high specificity, excellent reproducibility, good short-term stability and fast response time. Especially, it is indicated that the Ni/Cu-MOFs-FETs with high performance have the potential to be available sensors, paving the way for the application of bimetallic MOFs in biosensing.

The Space-Air-Ground integrated network (SAGIN) is the development trend of the future communication networks, and it can cope with various complex environments and tasks in the future communication environment. When sudden public events and natural disasters occurs, ground communication facilities may be damaged and cannot meet the communication needs in emergency scenarios. The Space-Air-Ground integrated three-dimensional and heterogeneous network enables flexible deployment and rapid networking. In this paper, we study the routing algorithm in a software defined SAGIN to optimize the load balancing in the communication network. First, considering the characteristics of dynamic topology changes in real time, we propose a new Software Defined Network (SDN) model for the SAGIN, which promotes a high network flexibility. Basing on such model, we present a new load balancing dynamic routing algorithm, namely Load Balancing Algorithm Based on Multi-dimensional Resources and Energy (LBMRE-OLSR). The multi-dimensional resources and energy consumption are considered in the new routing algorithm. The simulation experiments show that the proposed algorithm efficiently reduce end-to-end delays and packet loss rate.

Vanadium dioxide (VO2) has been widely studied due to its promising thermochromic property. VO2 nanoparticles film exhibits a unique nanothermochromic advantage with higher light transmittance (Tlum) and larger solar light transmittance modulation (∆Tsol) than continuous film. In this paper, a mild thermolysis method was developed to prepare VO2 nanoparticles with controlled size and morphology, which was then used to build the nanothermochromic films. By using vanadyl ethylene glycol (VEG) nanorods as a precursor, VO2 nanoparticles can be obtained at a thermolysis temperature as low as 250 °C within 5 min under static argon atmosphere. The VEG nanorods with uniform size and excellent dispersity were prepared from amorphous vanadium oxide nanopowders synthesized by electrochemical anodic-oxidation of vanadium target. The influence of the thermolysis conditions on the microstructure, phase transition and thermochromic properties of VO2 nanoparticles were investigated and discussed. By combining with transparent conductive substrate ITO, the VO2 nanoparticles films demonstrate an active optical switching performance, and the optimal thermochromic properties with Tlum of 48% and ∆Tsol of 11% can be achieved. Published version This work was financially supported by the National Natural Science Foundation of China (Grant nos. 51402304 and 51471163). Ming Li acknowledges the Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology (Grant no. 2018CXFX003) and Open Research Fund of State Key Laboratory of Pulsed Power Laser Technology (Grant no. SKL2018KF07).

Background/Aims: A major challenge for current therapeutic strategies against ischemia/reperfusion (I/R) is the lack of effective drugs. Considering luteolin enhances the activity of sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) to improve the systolic/diastolic function of rat hearts and cardiomyocytes during the I/R process, we studied the regulatory function of the p38 MAPK pathway in this protective mechanism. Methods: Isolated cardiomyocytes and perfused hearts were separately divided into five groups and used to investigate I/R. The phosphorylation of p38 and phospholamban (p-PLB), the levels and activity of SERCA2a and the levels of proteins related to apoptosis were measured. Apoptotic cells were assessed using the TUNEL assay. Single-cell shortening, Ca2+ transients, and the decay of the mitochondrial membrane potential (Δψm) were detected. Results: The p38 MAPK pathway was activated during the I/R process, and inhibiting it with SB203580 promoted p-PLB, which enhanced the activity of SERCA2a and relieved the calcium overload to promote the recovery of the Δψm and reduce cardiomyocyte apoptosis in I/R. Luteolin also suppressed the activation of the p38 MAPK pathway and showed cardioprotective effects during I/R injury. Conclusions: We conclude that luteolin enhances SERCA2a activity to improve systolic/diastolic function during I/R in rat hearts and cardiomyocytes by attenuating the inhibitive effects of the p38 pathway on p-PLB.

The microstructure, the mechanical properties and the oxidation behavior of a novel Ti-46.5Al-3Ta-2Cr-0.2W (at%) alloy after hot extrusion were investigated. The results show that the alloy is mainly composed of γ and α2 phases, which has fine near lamellar microstructure with colony sizes of 50∼70 μm after hot extrusion. The different microstructures after hot extrusion were obtained by different cooling rates, and a great amount of massive phase were found at grain boundaries by oil quenching. Tensile test results exhibit that the yield strength (YS) and ultimate tensile strength (UTS) of the alloy after hot extrusion decrease from 807 and 846 MPa at room temperature to 620 and 760 MPa at 800°C, respectively, and the elongation (EI) of the alloy increases from 2.16% at room temperature to 3% at 800°C which means that the alloy still keeps higher strength at elevated temperature. The observation of fracture surfaces shows that the crack length of the present alloy is smaller, and the additive of Ta increases the ductility of Ti-46.5Al-3Ta-2Cr-0.2W alloy at room temperature. The oxidation behavior of the novel TiAl based alloy in the experimental range was discussed. It is found that the addition of Ta can reduce the oxygen solubility into the TiAl alloy and suppress TiO2 growth at elevated temperature due to the low diffusivity.

Objective To observe the effects of oridonin on proliferation and apoptosis of myeloma RPMI8226 cells and to investigate the potential underlying mechanisms. Methods RPMI8226 cells were treated with various concentrations of oridonin. Cell proliferation was analyzed using the thiazolyl blue tetrazolium bromide method. Ultramicrostructure was observed by transmission electron microscopy. Annexin-V/PI staining and flow cytometry was performed to determine cell apoptosis. Expression of apoptosis-related proteins was evaluated by western blot analysis. Results Oridonin suppressed the proliferation of RPMI8226 cells and induced apoptosis in a time- and dose-dependent manner. Transmission electron microscopy confirmed apoptotic morphology upon treatment with 20 µmol/L oridonin and western blot revealed decreased expressions of the apoptosis suppressors survivin, Bcl-2 and pro-caspase-3 proteins, and the increased expression of the apoptosis inducer Bax. Conclusion Our results show that oridonin exhibits an inhibitory effect on the proliferation of RPMI8226 cells and induces apoptosis. This is associated with altering the balance between Bcl-2 and Bax protein expressions and decreased survivin and pro-caspase-3 expressions.

Objective: To describe the expression profiles of FOXA1, DUSP6, and HA117 in different portions of the colon of patients diagnosed with Hirschsprung’s disease (HSCR). Methods: Colon specimens were collected from34 HSCR patients and grouped into 3 segments: proximal anastomosis, dilated segment and stenotic segment. Levels of FOXA1, DUSP6, and HA117 RNA were evaluated by real-time PCR. Levels of FOXA1 and DUSP6 protein were analyzed by immunohistochemistry and Western blotting. Results: The levels of FOXA1 and DUSP6 RNA were significantly lower in the stenotic segment compared to proximal anastomosis (P < 0.05). The level of HA117 RNA was significantly higher in the stenotic segment compared to proximal anastomosis (P < 0.05). In proximal anastomosis, FOXA1 and DUSP6 were both expressed at the protein level in ganglion cells and nerve fibers between the circular and longitudinal muscles. In the stenotic segments, positive staining for FOXA1 and DUSP6 was diminished. The levels of FOXA1 and DUSP6 protein were significantly lower in the stenotic segment compared to proximal anastomosis (P < 0.05). Conclusion: Suppression of the FOXA1/DUSP6 signaling pathway may contribute to the development of HSCR. LncRNA HA117 may have an anti-differentiation function, and play a pivotal role in the progression of HSCR.

Objective To explore the optimised program-control mode of a dual-chamber pacemaker combined with β-blocker to treat congenital long QT syndrome (LQTS). Methods 12 LQTS patients in our hospital that still have symptoms despite use of regular drug therapies or that can not endure the therapies were implanted with DDD cardiac pacemaker. The QT/QTc intervals of those patients were measured at different pacing rates respectively. Their cardiac pacemakers were all programmed to selectively turn on and turn off some related functions at the pacing rate of 80 beats/min. The dosage of β-blockers was adjusted according to the patients’ PR intervals and blood pressures. The MACE and the cardiac function of the patients were recorded after operation. Results The measured QT/QTc interval decreased with the pacing rate increasing. The pacing rate of 80 beats/min can make QT/QTc interval basically normal. The MACE of the patients were statistically declined (p=0.003) and no negative effect on cardiac function was found during the follow-up. Conclusion The optimised program-control mode of a dual-chamber pacemaker combined with β-blocker to treat congenital LQTS are: to pace at the rate of 80 beats/min and program to turn off lag, sleep, automatic preventing PMT and automatic threshold-capture feature and turn on the PVC, rate adaptation and atrioventricular node priority function.

VSMCs Migration and proliferation are the critical pathological processes of various cardiovascular disease, such as atherosclerosis. Luteolin is a kind of flavonoids naturally occurring in many vegetables, fruits and medical plant. In this study, we investigated the effect of luteolin on the proliferation and migration of rat vascular smooth muscle cells (VSMCs) which were stimulated by H 2 O 2 , and a primary discussion was given to its mechanism of action. The present study demonstrated that Luteolin (12.5 to 50 μM) showed a particularly concentration-dependent inhibition effect on H 2 O 2 -elicited VSMCs proliferation and migration by MTT and Transwell assay respectively. In further research, we originally explored the function of Luteolin in blocking H 2 O 2 -triggered Src and Akt signalling pathways. The activation of Src, PDK1, Akt (308), Akt (473) of Luteolin group was significant lower than that of H 2 O 2 group. These findings strongly suggested that Luteolin suppressed H 2 O 2 -directed migration and proliferation in VSMCs by inactivating Src and Akt pathways which participate in VSMCs migration and proliferation.