Search

Detecting the environment around the supermassive black holes and tests of general relativity are important applications of extreme-mass-ratio inspirals (EMRIs). There is still a challenge to efficiently describe various “dirty” impacts on the inspirals, such as dark matter, gas, dipole radiation, and electromagnetic interaction. In this study, we find the inherent linearity of the asymptotic solution of the inhomogeneous Teukolsky equation. On the basis of this property, we completely decouple the factors of the perturber and the background spacetime in the energy fluxes and waveforms. With the new decoupling form, the waveforms of EMRIs with non-geodesic motion in Kerr spacetime can be conveniently calculated. This will help to resolve the environment (including gas, field, dark matter, electromagnetic interaction) around supermassive black holes and test general relativity. [ABSTRACT FROM AUTHOR]

Sepsis, a critical health condition induced by an overactive innate immune response and reactive oxygen species (ROS)-driven host damage through apoptosis and ferroptosis, continues to pose a significant mortality risk. Despite accumulating evidence of the potential therapeutic properties of tea ingredients, their specific anti-sepsis potential remains inadequately explored. This study comprehensively investigates the targeted genes of tea ingredients, notably epigallocatechin 3-gallate (EGCG), and their correlation with sepsis signature genes. Our findings elucidate that tea ingredients, especially EGCG, exhibit substantial potential in mitigating inflammation and sepsis-induced damage. Through the inhibition of the MAPK cascade and macrophage activation and by impeding the transcriptional activity of RELA (transcription factor p65) in sepsis, EGCG demonstrates significant anti-sepsis efficacy. Molecular docking analysis further underpins this by revealing the close proximity of EGCG and (−)-catechin gallate binding sites to that of RELA on DNA. Subsequent in vitro assays illuminated EGCG's instrumental role in modulating macrophage M2 polarization, balancing M1 and M2 differentiation of bone marrow-derived macrophages (BMDMs), curtailing inflammatory factor secretion, and inhibiting ROS production. Moreover, EGCG effectively suppresses the expression of ferroptosis/apoptosis markers in LPS-induced macrophages during their early stages. Our study advances our understanding of sepsis prevention and treatment strategies, suggesting that tea ingredients such as EGCG could play a pivotal role in developing future sepsis therapies due to their protective effects. [ABSTRACT FROM AUTHOR]

The inspiral of compact stellar objects into massive black holes are one of the main astrophysical sources for the Laser Interferometer Space Antenna (LISA) and Taiji. These extreme-mass-ratio inspirals (EMRIs) have great potential for cosmology and fundamental physics. A binary extreme-mass-ratio inspiral (b-EMRI) describes the case where binary black holes (BBHs) are captured by a supermassive black hole. The b-EMRIs serve as multi-band gravitational wave sources and provide insights into the dynamics of nuclei and tests of general relativity. However, if the b-EMRIs can be distinguished from the normal EMRIs or not is still not clear. In this work, with a few of assumptions, and using the Teukolsky equation, we calculate the approximate gravitational waves of b-EMRIs and assess their detectability by space-based detectors. We also decouple the secondary object information from the Teukolsky equation, enabling us to calculate the energy fluxes and generate the waveforms more conveniently. Variations in the quadrupole of the binary result in small but non-negligible changes in energy fluxes and waveforms, making it possible to distinguish b-EMRI signals with data analysis. This opens up the potential of using b-EMRIs to test gravity theories and for further astrophysical studies. [ABSTRACT FROM AUTHOR]

The Oxyfluoride glass ceramics (GCs) containing Na5Y9F32:Ce3+/Tb3+ nanocrystals were synthesized using a high-temperature melting method. The microstructural, luminescent property, energy transfer, and thermal stability of the samples were investigated. Under 310 nm excitation, the co-doped GCs exhibited two emissions at blue 380 nm (Ce3+: 5d → 4f) and green 542 nm (Tb3+: 5D4 → 7F5). The luminous color can be tuned from blue (0.1966, 0.1512) to yellow–green (0.288, 0.4473) by increasing the content of Tb3+ ions. Decay curves revealed efficient energy transfer from Ce3+ to Tb3+, with an energy transfer efficiency (ETE) of up to 47.54%. According to the theory of Dexter energy transfer, dipole–dipole interaction was confirmed as the mechanism for energy transfer between Ce3+ and Tb3+. Moreover, the prepared GCs demonstrated good thermal stability even at elevated temperatures. These findings indicate that the Na5Y9F32: Ce3+/Tb3+ GCs can serve as materials for W-LEDs, excited by near-ultraviolet light, to enhance of green light emission. [ABSTRACT FROM AUTHOR]

We combined untargeted and targeted metabolomics to explore the mechanism of blood circulation and blood stasis activation in the traditional Chinese herb pair Panax notoginseng–Salvia miltiorrhiza (PS). In this study, the right hind limb of SD rats was struck by a 1 kg weight, causing traumatic blood stasis (TBS) model, then the rats were gavaged with PS (at ratios of 1:0, 0:1, 3:1, 1:1, and 1:3) for 5 consecutive days. At the end of treatment, blood samples were collected for blood rheology and metabolomics analysis, and muscle tissues of injured limbs were used for HE staining and q-PCR analysis. The results showed that different ratios of PS reduced swelling and improved stasis and blood viscosity in the injured limbs of rats, and intervened in metabolism by modulating 11, 11, 17, 15, and 13 differential metabolites, respectively. The PS (3:1) shows the best treatment effect and the most differential metabolites regression. Targeted metabolomics shows that PS (3:1) can increase the content of AA, and reduce the content of PGF2-α by down-regulating the expression of enzymes Ptgs1 and Cbrl12 and up-regulating the expression of enzyme Hpgd. These results suggested that the PS herb pair exerts its blood stasis activating effects by blocking the conversion of arachidonic acid to prostaglandins. [ABSTRACT FROM AUTHOR]

Objective: Little is known about the magnitude of the relation of ambient fine particulate matter (PM2.5) constituents with hyperuricemia and serum uric acid (SUA) levels. Therefore, we aimed to assess the associations and to identify the most hazardous constituent. Methods: This study included 72,840 participants from the China Multi-Ethnic Cohort. Annual average concentrations of PM2.5 mass and its major 7 constituents were matched to individuals by residential address. SUA levels exceeding 7.0 mg/dL (417 μmol/L) for men and 6.0 mg/dL (357 μmol/L) for women were considered to be hyperuricemia. Multiple logistic and linear regressions were performed on the association of single exposure to PM2.5 constituents with hyperuricemia and SUA, separately. The weighted quantile sum method was applied to examine the joint effect of PM2.5 constituents on hyperuricemia/SUA. Results: Significant positive associations were discovered between PM2.5 constituents and SUA/hyperuricemia. For example, the odds ratio (95% confidence interval) of hyperuricemia for per standard deviation increase of PM2.5 mass, black carbon, organic matter, ammonium, and nitrate concentrations were 1.22 (1.12–1.32), 1.17 (1.08–1.27), 1.20 (1.10–1.31), 1.21 (1.11–1.31), and 1.28 (1.18–1.40), respectively. The joint exposure to PM2.5 constituents was significantly positively correlated with hyperuricemia (1.09, 1.05–1.14) and SUA (1.05, 1.03–1.06). And the weight of nitrate was the largest (0.668 for hyperuricemia, 0.586 for SUA). Conclusions: Our findings suggest that long-term exposure to PM2.5 constituents is associated with increased SUA levels and a higher risk of hyperuricemia. In particular, nitrate seems to be the main contributor. This study may help prevent hyperuricemia by promoting the introduction of precise preventive measures. Highlights: Considering the constituents of PM2.5 in assessing its toxicity and health effects. Exposure to PM2.5 constituents was related with serum uric acid and hyperuricemia. Nitrate contributed most to serum uric acid levels and hyperuricemia. The results of joint effects were verified by two different statistical methods. A large-scale sample of nearly 100,000 subjects from diverse ethnic backgrounds. [ABSTRACT FROM AUTHOR]

This paper improves the vibration isolation effect of the conventional wave impeding block by double-layer wave impeding block with the same thickness. Based on the theory of wave motion in unsaturated porous medium and elastic medium, the vibration isolation performance of double-layer wave impeding block in unsaturated foundation under SV wave incidence is studied. Based on the Helmholtz principle, the solutions of surface vertical displacements of the unsaturated foundation under SV wave incidence are obtained. The influence of the wave impedance ratio between the layers of double-layer wave impeding block and the wave impedance ratio at the interface between the wave impeding block and the unsaturated soil foundation are firstly studied, and it was found that the optimal vibration isolation effect could be obtained by designing and controlling the wave impedance ratio between the layers of the double-layer wave impeding block and the wave impedance ratio at the interface between the wave impeding block and the unsaturated foundation. Then the physical and mechanical parameters such as incidence angle, incidence frequency, saturation, thickness and burial depth of the double-layer wave impeding block were analyzed to determine the influence on the vibration isolation performance of the double-layer wave impeding block. The results show that the best vibration isolation effect of double-layer wave impeding block is achieved at 5° of S-wave incidence angle. The double-layer wave impeding block has better vibration isolation effect at low frequency, medium frequency and high frequency. The vibration isolation effect of double-layer wave impeding block increases and then decreases with an increase of saturation, increases with an increase of burial depth and thickness, decreases and then increases with an increase of incident frequency. [ABSTRACT FROM AUTHOR]

Neural networks, primarily recurrent and convolutional Neural networks, have been proven successful in text classification. However, convolutional models could be limited when classification tasks are determined by long-range semantic dependency. While the recurrent ones can capture long-range dependency, the sequential architecture of which could constrain the training speed. Meanwhile, traditional networks encode the entire document in a single pass, which omits the hierarchical structure of the document. To address the above issues, this study presents T-HMAN, a Topic-aware Hierarchical Multiple Attention Network for text classification. A multi-head self-attention coupled with convolutional filters is developed to capture long-range dependency via integrating the convolution features from each attention head. Meanwhile, T-HMAN combines topic distributions generated by Latent Dirichlet Allocation (LDA) with sentence-level and document-level inputs respectively in a hierarchical architecture. The proposed model surpasses the accuracies of the current state-of-the-art hierarchical models on five publicly accessible datasets. The ablation study demonstrates that the involvement of multiple attention mechanisms brings significant improvement. The current topic distributions are fixed vectors generated by LDA, the topic distributions will be parameterized and updated simultaneously with the model weights in future work. [ABSTRACT FROM AUTHOR]

Hydrogen-rich water (HRW) has been shown to improve the growth of rice under stressful conditions. However, the effects of HWR on the growth and development and stress resistance physiology of fragrant rice seedlings under nitrogen deficiency conditions are not clear. A pot experiment was conducted by using two fragrant rice varieties i.e., Yuxiangyouzhan and Xiangyaxiangzhan as materials. In this experiment, two nitrogen (N) treatments (LN: 1/4 strength of Kimura nutrient solution and MN: full strength of Kimura nutrient solution) and two HRW treatments (CK: Kimura nutrient solution without H2 and HRW: Kimura nutrient solution contains 500 ppb H2) that are four treatments including MN-CK, MN-HRW, LN-CK and LN-HRW for each variety. Treatments were applied at the two-leaf stage of fragrant rice and morphological and physiological and biochemical attributes were investigated at 5 and 10 day after treatment (DAT). The results showed that, under nitrogen deficiency conditions, the HRW treatment promoted the growth of fragrant rice seedlings in terms of increased biomass of the whole seedling at 10 DAT. Compeared LN-CK, LN-HRW treatment increased malondialdehyde content of shoot of Yuxiangyouzhan and Xiangyaxiangzhan, increased catalase activity of root at 10 DAT of Yuxiangyouzhan, increased peroxidase activity at 5 DAT of Xiangyaxiangzhan. It can be seen that HRW is able to reduce the stress of low nitrogen on fragrant rice to some extent, and that the reduction of this stress is largely dependent on improving the growth rate of fragrant rice seedlings and increasing the activity of representative antioxidant enzymes. [ABSTRACT FROM AUTHOR]

The chemical stability, electronic structures, mechanical properties and Debye temperature of Fe–Mn–Al alloys were investigated using first-principles calculations. The formation enthalpy and cohesive energy are negative for Fe–Mn–Al alloys, showing that they are thermodynamically stable. FeAl has the lowest formation enthalpy, indicating that FeAl is the most stable alloy in the Fe–Mn–Al system. The partial density of states, total density of states and electron density distribution maps were used to analyze the physical properties of the Fe–Mn–Al alloys. A combination of mainly covalent and metallic bonds exists in these Fe–Mn–Al alloys, resulting in good electronic conductivity, high melting points, and high hardness. These alloys display disparate anisotropy due to the calculated different shapes of the 3D curved surface of the Young's modulus and anisotropic index. FeAl has the highest bulk modulus, shear modulus and Yong's modulus of 187.1, 119.8 and 296.2 GPa, respectively. Further, the Debye temperatures and sound velocity of these Fe–Mn–Al compounds were explored. [ABSTRACT FROM AUTHOR]

We developed a hollow fiber centrifugal ultrafiltration (HFCF-UF) method to study the change of plasma levels of free glycine (Gly) in patients with acute ischemic stroke (AIS). Twenty-four patients with AIS confirmed by diffusion-weighted imaging (DWI) were enrolled. During the study period, the patients did not receive any supplemental amino acids therapy that could affect the obtained results. Our results showed that although AIS patients adopted different methods of treatment (thrombolytic and non-thrombolytic), the clinical NIHSS score of AIS showed a downward trend whereas Gly concentration showed increased trend. Moreover, plasma free Gly concentration was positively correlated with ASPECTS score. The correlation between Gly levels and infarct volume showed a statistical significance. That is to say, higher Gly level predicted smaller infarct size. Thus, the change of free Gly level in plasma could be considered as a potential biomarker of AIS. [ABSTRACT FROM AUTHOR]

Driven by sustainable development, the energy-saving manufacturing and on-site repairing processes for fiber-reinforced polymer (FRP) composites are highly desired to replace the conventional autoclave or oven. In this work, the flexible, thin free-standing laser-induced graphene (FS-LIG) film was obtained by one-step laser irradiation on polybenzoxazine resin followed by rapid quench-peeling. The FS-LIG film showed the uniform, low-voltage driven, and long-term stable Joule heating effect. With attractive Joule performance, the FS-LIG film was developed as a heater for the out-of-autoclave fabrication of FRP composites. Compared with the conventional oven curing process, the FS-LIG-based Joule heating saved around 45% of the energy required without compromising the mechanical performance of obtained composites. Moreover, the FS-LIG film was interlayered into FRP composites to prepare the self-heating patch, which could not only provide heat for the on-site repair of structural composites but also serve as the reinforcement for mechanical properties. Furthermore, the integration of FS-LIG layer enabled the cured composites with additional functionalities including temperature and mechanical sensing to monitor the structural health of composites. This easy-fabricated FS-LIG heater showed enormous practical promise in the advanced manufacturing and repairing of composites. [ABSTRACT FROM AUTHOR]

Nitrogen (N) modulates plant growth, but its impact on the early growth and physio-biochemical characteristics of rice under cadmium (Cd) and multiwall carbon nanotubes (MWCNTs) toxicity has received little attention. In this study, a hydroponic experiment was conducted on two fragrant rice cultivars, e.g., Xiangyaxiangzhan (XYXZ) and Yuxiangyouzhan (YXYZ), grown under two N levels (N and 1/4 N) and various Cd and MWCNTs treatments (CK: without CdCl2 or MWCNTs; Cd: 100 μmol L−1 CdCl2; MWCNTs: 100 mg L−1 MWCNTs; and Cd-MWCNTs: 100 μmol L−1 CdCl2 + 100 mg L−1 MWCNTs). Results showed that when compared to CK, the total dry weight of the Cd and MWCNTs treatments did not change under 1/4 N for both varieties, whereas Cd and Cd-MWCNTs treatments resulted in a significant reduction in total dry weight by 18.78–37.85% for XYXZ and the Cd-MWCNTs treatment resulted in a significant reduction in the total dry weight by 20.24% for YXYZ. The changes in total dry weight were linked to changes in the dry weight of the different parts of the plant. Besides, the antioxidant parameters and the enzymes involved in the nitrogen metabolism changed in different varieties and different plant parts under two N levels and various Cd and MWCNTs treatments. In addition, differences in total dry weight changes at the N levels and various Cd and MWCNTs treatments were identified between the two varieties, and the relations between total dry weight and other investigated parameters indicated that the modulation processes varied between varieties. Overall, N modulates the early growth and physio-biochemical attributes in fragrant rice seedlings under Cd, MWCNTs, and their combined toxicity. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the therapeutic effect of JQ-R on metabolic hypertension and its correlation with Fibroblast growth factor 21/Fibroblast growth factor receptors 1(FGF21/FGFR1) pathway. In this study, fructose-induced metabolic hypertension rats were used as hypertension models to detect the regulation effect of JQ-R on hypertension. The effects of JQ-R on blood glucose, blood lipids, serum insulin levels and other metabolic indicators of rats were also measured. The effects of JQ-R on FGF21/FGFR1 signaling pathway in model animals were detected by Real-time quantitative PCR and Western blotting. The results showed that JQ-R significantly reduce the blood pressure of model rats in a dose-dependent manner. Meanwhile, fasting insulin, fasting blood glucose, insulin resistance index, total cholesterol and triglyceride levels were significantly decreased, and glucose and lipid metabolism abnormalities were also significantly improved. JQ-R induces these changes along with FGFR1 phosphorylation, which was also detected in JQ-R treated FGF21 knockout mice. These results suggest that JQ-R can reduce blood pressure and improve glucose and lipid metabolism in fructose-induced hypertension rats. Activation of FGF21/FGFR1 signaling pathway to regulate downstream blood pressure and glucolipid metabolism-related pathways may be one of the important mechanisms of JQ-R in regulating blood pressure. [ABSTRACT FROM AUTHOR]

Effect of solution treatment on microstructure and mechanical properties of Al-12Si-4Cu-2Ni-0.8Mg-0.2Gd alloy was investigated. Results show the Si particles become stable and more intermetallic compounds dissolve in the matrix after solution treatment at 500 °C for 2 h followed by 540 °C for 3 h (T4). The skeleton-like Al3CuNi develops into two parts in the T4 alloy: one is Al3CuNi which has the framework shape; the other is intermetallics including the Al3CuNi (size: 5–10 µm) and AlSiCuNiGd phases (size: ≤5 µm) with complex structure. Adding 0.2% Gd can improve the mechanical properties of the alloys after two-step solution treatment (500 °C/2 h followed by 540 °C/3 h), the hardness of the alloy increases from 130.9 HV to 135.8 HV compared with the alloy with one-step solution treatment (500 °C/2 h), the engineering strength increases from 335.45 MPa to 352.03 MPa and the fracture engineering strain increases from 1.44% to 1.67%. [ABSTRACT FROM AUTHOR]

Aims: Grazing is a key driver of plant communities and soil functions in grassland ecosystems. Soil nematodes play a vital role in soil ecological functions. The aim of this study was to explore how grazing shapes soil nematode community in different soil layers. Methods: We investigated the composition, abundance, diversity, metabolic footprint, and food web metrics of soil nematodes over a gradient of grazing in the 0–10 cm and 10–20 cm soil layers in a meadow steppe. The relationships between nematode community structure and biotic and abiotic factors were analyzed by principal component analysis and structural equation model analysis. Results: Light grazing increased the abundance of total soil nematodes by 18.5%. Intensive grazing decreased the carbon used in production and metabolic footprints of plant parasites, fungivores, and total soil nematodes in 0–10 cm soils. There was no difference in the carbon used in production and metabolic footprints of soil nematodes among different grazing intensities in the 10–20 cm soil layer. Soil moisture, aboveground biomass, belowground biomass and Shannon diversity of grass contributed more to changes in soil nematode composition in both soil layers. In the 0–10 cm soil layer, grazing directly and indirectly affected soil nematode diversity via soil moisture and aboveground biomass, while grazing directly affected soil nematode diversity in 10–20 cm soil layer. Conclusions: Our results indicate that increasing soil depth can weaken the effect of grazing intensities on soil nematode fauna. Grazing affected the soil nematode community structure via different paths in different soil layers. [ABSTRACT FROM AUTHOR]

The presence of reduced aminothiols, including homocysteine (Hcy), cysteine (Cys), cysteinyl-glycine (CG), and glutathione (GSH), is significantly increased in the pathological state. However, there have been no reports on the relationship between reduced aminothiols (Hcy, Cys, CG, and GSH) and different genders, ages, and drug combinations in human blood. The accurate quantification of these reduced thiols in biological fluids is important for monitoring some special pathological conditions of humans. However, the published methods typically not only require cumbersome and technically challenging processing procedures to ensure reliable measurements, but are also laborious and time-consuming, which may disturb the initial physiological balance and lead to inaccurate results. We developed a hollow fiber centrifugal ultrafiltration (HFCF-UF) method for sample preparation coupled with a high-performance liquid chromatography–tandem mass spectrometry (HPLC-MS/MS) method and used it to determine four reduced aminothiols (Hcy, Cys, CG, and GSH) in human blood for the first time. A total of 96 clinical patients were enrolled in our study. The influence of different genders, ages, and drug combinations on the levels of four reduced thiols in human blood was also discussed by SPSS 24.0. The sample preparation was simplified to a single 5 min centrifugation step in a sealed system that did not disturb the physiological environment. The validation parameters for the methodological results were excellent. The procedure was successfully applied to monitoring the concentrations of four reduced aminothiols (Hcy, Cys, CG, and GSH) in 96 clinical blood samples. There were no significant differences in Hcy, Cys, CG, or GSH for the different genders, ages, or combinations with methotrexate or vancomycin (P > 0.05). However, there was a significant increase in Hcy concentration in patients treated with valproic acid who were diagnosed with epilepsy (p=0.0007). It is advisable to measure reduced Hcy level in patients taking valproic acid. The developed HFCF-UF method was simple and accurate. It can be easily applied in clinical research to evaluate oxidative stress in further study. [ABSTRACT FROM AUTHOR]

Purpose: China was affected by an outbreak of coronavirus disease 2019 (COVID-19) in 2019–2020. Research data are needed to develop evidence-driven strategies to reduce the adverse psychological and occupational impacts on healthcare workers (HCWs). Methods: From March 1, 2020, to March 8, 2020, 946 HCWs in China completed a survey consist of sociodemographic data, precautionary measures against COVID-19, and concerns about COVID-19. Self-administered questionnaire were collected to assess psychological and occupational adverse outcomes of HCWs. Multivariable logistic regression analysis was performed to identify factors associated with the outcomes. Results: A total of 55.0%, 56.0% and 48.3% of the HCWs experienced burnout, psychological distress and posttraumatic stress, respectively. A total of seven factors were independently associated with burnout: good health status (OR 0.51, 95% CI 0.36–0.71), fear of contagion (OR 1.31, 95% CI 1.003–1.79), avoiding contact with children (OR 1.40, 95% CI 1.03–1.91), enough staff support at the workplace (OR 0.59, 95% CI 0.38–0.92), having to work overtime (OR 1.37, 95% CI 1.03–1.83), maladaptive coping (OR 3.28, 95% CI 2.42–4.45) and adaptive coping (OR 0.47, 95% CI 0.35–0.62). A total of 11 factors were independently associated with high psychological distress: having one child (OR 0.54, 95% CI 0.38–0.77), good health status (OR 0.57, 95% CI 0.39–0.83), alcohol abuse (OR 1.51, 95% CI 1.02–2.25), thinking the epidemic would continue for quite a long time (OR 1.59, 95% CI 1.08–2.34), wearing extra-work clothes (OR 1.51, 95% CI 1.06–2.15),effective protective equipment (OR 0.45, 95% CI 0.22–0.90), enough staff support at the workplace (OR 0.55, 95% CI 0.34–0.89), unable to take care of families (OR 1.99, 95% CI 1.42–2.78), economic losses (OR 1.62, 95% CI 1.14–2.31), maladaptive coping (OR 6.88, 95% CI 4.75–9.97),and adaptive coping (OR 0.29, 95% CI 0.21–0.41). These factors were independently associated with posttraumatic stress: living with the elderly (OR 1.46, 95% CI 1.04–2.05), alcohol abuse (OR 1.41, 95% CI 1.002–1.98), working at a 3A hospital(OR 0.66, 95% CI 0.49–0.88), acquaintances confirmed COVID-19 (OR 2.14, 95% CI 1.20–3.84), fear of contagion (OR 1.87, 95% CI 1.40–2.50), believing they would survive if infected (OR 0.63, 95% CI 0.46–0.86), self-disinfected after arriving home (OR 1.43, 95% CI 1.01–2.02), interpersonal isolation (OR 1.65, 95% CI 1.21–2.26), unable to take care of families (OR 1.41, 95% CI 1.05–1.88) and maladaptive coping (OR 3.09, 95% CI 2.32–4.11). Conclusion: The variance in adverse outcomes was explained by the effect of various factors, which will help policymakers better prepare for subsequent potential outbreaks of COVID-19. [ABSTRACT FROM AUTHOR]

In order to prevent gas leakage, gas sensors are routinely deployed in chemical industrial parks to monitor it. However, because of the effects of weather conditions, such as wind speed and direction, these gas sensors may not be able to accurately monitor the concentration of the gas leak. Toxic and harmful gases not only do harm to the surrounding environment, but also to the health of nearby residents. In order to effectively monitor the occurrence of gas leakage, in this paper, a plan of setting up wireless sensor network on site is designed, which is based on the meteorological and gas characteristics. What's more, the plan includes the rectangle plan, the fan plan and the annular plan. Also, it stipulates the optimization standard of sensor node position and deployment scheme and field experiments were carried out in the chemical industrial park, whereby the monitoring values of gas concentration in different schemes were obtained. According to the standards, the optimal deployment scheme and the optimal location of sensor nodes in different schemes are also procured. The results show that the method is feasible and effective. It can optimize the deployment position of different elevation under certain wind speed and wind direction as well as optimize different solutions. [ABSTRACT FROM AUTHOR]

The high entropy alloy (HEA) coatings are potential candidates for advanced application in the protection of steel and other traditional alloys due to their excellent physical and mechanical performance. The AlCoCrFeNi alloy series were favorably studied due to comparably low cost and stable performance. In this research, the AlCoCrFeNi coatings were prepared through surface mechanical abrasion treatment (SMAT). The process implied the comprehensive effect of cold welding and friction. The submicron-size SiC particles were added into the raw materials in different amounts. For SMAT, a high-energy ball milling method was adopted to promote the alloying of metals, disperse SiCp, and combine the powder to the carbon steel substrate. Afterward, the phase composition, microstructure of coatings, and distribution of reinforcement were detected through XRD and SEM analysis, separately, and the effect of SiC particles content on the properties of the coatings was analyzed. The results show that the addition of submicron-sized SiC significantly improved the density and stiffness of the HEA coating and diminished defects and surface roughness. Сoatings containing SiC display enhanced adhesion force and wear resistance. The proposed mechanism is that the submicron SiC particles promoted mechanical alloying of pure metal and intensified the adherence and cold welding of the coating. Especially, herein, the addition of 15 wt.% SiC granted the best comprehensive properties of the coating. Excessive SiC content led to the deterioration of coating plasticity and the growth of cracks. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)-based dispersive solid phase extraction (D-SPE) method combined with multi-step preparation has been put forward for the evaluation of trace ochratoxin A (OTA) in chicken liver. The homogenized tissue sample was initially clean-up and extracted with petroleum ether, ethyl acetate and 0.1 mol/L sodium bicarbonate solution and then adsorbed using GO originally targeting for OTA. The adsorbed OTA was then eluted twice by 1 mL of methanol and finally quantified by high performance liquid chromatography fluorescence detection (HPLC-FD). As a result, the matrix effect of chicken liver tissue was removed to a great extent after a series of processing steps. Under the optimum conditions, the functionality of the method was attested and this method demonstrated proper sensitivity, with detection and quantification limits equal to 0.02 ng/mL and 0.04 ng/mL, respectively. The method turned out to be accurate with recoveries ranging from 86.4 to 102.9%. Furthermore, the established method was applied to assess OTA contamination in different batches chicken liver, which revealed that two supermarket-sold and three individual domestic samples were contaminated with OTA (33% frequency) and the proposed method was suitable for continuous monitoring for OTA in chicken liver to ensure food safety. [ABSTRACT FROM AUTHOR]

Background and Aims: Plant-parasitic nematodes are able to sense and respond to gradients of chemical signals. How pH and inorganic salts in the rhizosphere affect nematode accumulation and host-seeking is poorly understood. We investigate the response of different groups of plant-parasitic nematodes to pH and salt concentration gradients. Methods: Responses of infective juveniles (J2) of the economically important plant-parasitic nematodes, soybean cyst nematodes (SCN; Heterodera glycines) and root-knot nematodes (RKN; Meloidogyne incognita and M. hapla) to pH and salt gradients were assessed using Pluronic F-127 gel-based assays. Microelectrodes were utilized to measure pH and ion concentration gradients in the gel. Key Results: Differences were found between the three nematode species in response to acid, base and salts. For SCN, maximum nematode accumulation was between pH range 4.98–5.46 in an acid gradient, while the preferred alkaline pH ranges were 8.40–8.78 and 9.52–9.99. The preferred Cl− concentration for SCN attraction was 171–256 mM. RKN showed weak attraction to base and salt at low J2 concentration but increasing attraction at a greater nematode concentration. Conclusions: The pH and inorganic salts affect nematode behavior, accumulation, and survival. These findings provide new considerations for strategies to manage plant-parasitic nematodes under field conditions. [ABSTRACT FROM AUTHOR]

The Cu/ZnO/Al2O3 catalysts prepared by co-precipitation method were used for the hydrogenation of methyl benzoate to benzyl alcohol. These catalysts were characterized at various stages of preparation by nitrogen adsorption-desorption, X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS). The experimental results show that the addition of ZnO to the catalyst greatly improves the selectivity of benzyl alcohol. When the Cu/Zn/Al molar ratio is 2:2:1 and the calcination temperature of the catalyst is 650 °C, the catalyst exhibits very highly catalytic performance. In addition, the effects of reaction temperature, pressure and time were also investigated during the hydrogenation of methyl benzoate to benzyl alcohol. When the methyl benzoate was hydrogenated over this catalyst at 160 °C and 7 MPa of H2 for 10 h, the conversion of methyl benzoate can reach 93.89% and the selectivity of benzyl alcohol is 88%. This effectively catalytic performance can be attributed to the presence of highly dispersed and stable metallic copper nanoparticles, and the weak acidity of the catalyst surface. Besides, the reaction pressure and temperature play a crucial role in the conversion of methyl benzoate and the selectivity of benzyl alcohol.Graphical Abstract: Application of Cu/ZnO/Al2O3 catalyst in hydrogenation of methyl benzoate to benzyl alcohol. [ABSTRACT FROM AUTHOR]

Abstract: In this work, titanium-doped mesoporous Al2O3 (γ-Ti-Al2O3) was prepared by an evaporation-induced self-assembly method and used as a carrier of Ba/γ-Ti-Al2O3 catalyst to catalyze the aldol condensation of methyl acetate with formaldehyde to methyl acrylate in a fixed-bed reactor. The catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, N2 adsorption-desorption, pyridine absorption performed via Fourier transform infrared spectroscope (Py-IR), and NH3 and CO2 temperature-programmed desorption (NH3 and CO2-TPD). Experimental results indicated that the doping of the titanium species into the frame work of mesoporous Al2O3 (γ-Ti-Al2O3) had a significant influence on the catalytic activity via modifying the acid-base surface properties of the catalyst. Furthermore, the Ba/γ-Ti-Al2O3 catalyst demonstrated excellent catalytic performance, with a methyl acetate conversion rate of 50% and methyl acrylate selectivity up to 90.2%. Compared with the Ba/Al2O3 catalyst, the Ba/γ-Ti-Al2O3 catalyst had better catalytic activity, stability and potential for practical application, which was likely due to an increased number of Lewis acid sites, especially the medium acid sites.Graphical Abstract: Barium supported mesoporous γ-Ti-Al2O3 catalyst was found to be an effective catalyst for vapor phase aldol condensation of methyl acetate with formaldehyde. [ABSTRACT FROM AUTHOR]

Abstract: A series of Ca doped Ce-Ti oxides prepared by a single step sol-gel method were investigated for the selective catalytic reduction of NO with NH3. The results show that Ca doping had both positive and negative effects on the activities of Ce-Ti oxide. Ca0.1CT possessed the best catalytic activity and widest temperature window. Further investigations on BET, XRD, XPS, H2-TPR and NH3-TPD demonstrated that the good SCR performance of Ca0.1CT could be attributed to the increase in the amount of Ce3+ and surface adsorbed oxygen as well as the enhancement of Brønsted acidity and redox ability. In addition, the good dispersion of active Ce species, the alleviation of support sintering, and the interaction among Ce, Ti and Ca species were also responsible for its enhanced activity.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Tylototriton ziegleri is distributed in northern Vietnam and is a new member of the genus Tylototriton. The conservation status of this species has not yet been assessed by the IUCN, but several other species of Tylototriton have been listed as near threatened or vulnerable due to habitat destruction and illegal hunting. We determined the complete sequence and structural characteristics of the mitochondrial genome of T. ziegleri. The entire mitogenome is 16,266 bp in length, and contains 13 protein-coding genes, 22 tRNA genes, two rRNA genes, a control region, and a non-coding region. The length, gene arrangement, and composition are similar to mitogenomes of other species of Tylototriton. A phylogenetic tree based on the mitogenome sequences of several Asian species within Salamandridae confirmed the genus Tylototriton as monophyletic, with T. ziegleri being the sister species of T. asperrimus and both constituting the sister group of T. wenxianensis. This work provides basic molecular data which are critical for further genetic research and conservation of the genus Tylototriton. [ABSTRACT FROM AUTHOR]

Tribological behavior of Cu−15Ni−8Sn (mass fraction, %) alloy against GCr15 ring under various loads was investigated on a ring-on-block tester in oil lubrication. The results showed that the wear rate increased slowly from 1.7×10 to 9.8× 10 mm3/mm under the load lower than 300 N, and then increased dramatically to the climax of 216×10 mm/mm under the load over 300 N, which indicated the transition of wear mechanism with the increase of applied load. The wear mechanism mainly was plastic deformation and abrasive wear under the load less than 300 N. As the applied load was more than 300 N, the wear mechanism of Cu−15Ni−8Sn alloy primarily was delamination wear. Besides, the transition can also be confirmed from the different morphologies of worn surface, subsurface and wear debris. It is distinctly indicated that the appearance of flaky debris at the applied load over 300 N may be a critical point for the change of wear mechanism. [ABSTRACT FROM AUTHOR]

Chinese soft-shelled turtle ( Pelodiscus sinensis) is a favorite food for the Asian because of its high nutritional and medicinal value. Based on an estimate production of 350,000 MT in 2015, soft-shelled turtle culture industry in China values US$5.22 billion. In central China, overwinter in greenhouse is necessary for the juvenile turtle. The use of coal boiler to heat up the water to 30 °C is a common practice, however, brings in air pollution and CO emission too. A modern greenhouse equipped with ground source heat pump was built in 2010 and operated during 2014-2015 for 10 months to culture juvenile turtle. Besides heating system, the other innovative features such as skirt-shaped 3-D shelter, underwater feeding platform wok-shaped tank bottom with central drainage, and semi-homemade soft shell-shaped pellet together achieved excellent rearing performance, such as high turtle productivity of 23.7 kg m, high survival 86%, low feed efficiency-feed conversion rate 1.26 and good water quality-dissolved oxygen >5 mg L, and nitrite and ammonia concentration all time within safe range. Moreover, it is a lucrative business which brought in an estimated net profit of 76%. [ABSTRACT FROM AUTHOR]

Main conclusion : The tea plant ( Camellia sinensis L. O. Kuntze) is a high aluminum (Al) tolerant and accumulator species. Candidate genes related to Al tolerance in tea plants were assembled based on de novo transcriptome analysis. The homologs implied some common and distinct Al-tolerant mechanism between tea plants and rice, Arabidopsis and buckwheat. In addition to high Al tolerance, the tea plant exhibits good performance exposure to a proper Al level, and accumulates high Al in the leaves without any toxicity symptom. Therefore, Al was considered as a hyperaccumulator and beneficial element for tea plants. However, the whole-genome molecular mechanisms accounting for Al-tolerance and accumulation remain unknown in tea plants. In this study, transcriptome analysis by RNA-Seq following a gradient Al-level exposure was assessed to further reveal candidate genes involved. Totally more than 468 million high-quality reads were generated and 213,699 unigenes were de novo assembled, among which 8922 unigenes were all annotated in the seven databases used. A large number of transporters, transcription factors, cytochrome P450, ubiquitin ligase, organic acid biosynthesis, heat shock proteins differentially expressed in response to high Al ( P ≤ 0.05) were identified, which were most likely ideal candidates involved in the Al tolerance or accumulation. Furthermore, a few of the candidate Al-responsive genes related to Al sequestration, cell wall modification and organic acid excretion have been well elucidated as was already found in Arabidopsis, rice, and buckwheat. Thus, some consistent Al-tolerance mechanisms across the species are indicated. In conclusion, the transcriptome data provided useful insights of promising candidates for further characterizing the functions of genes involved in Al tolerance and accumulation in tea plants. [ABSTRACT FROM AUTHOR]

The effect of CaO on CeO/TiO catalysts prepared by a single step sol-gel method for selective catalytic reduction of NO with NH was investigated. The results showed that CaO could severely deactivate the CeO/TiO catalysts. Based on the characterization results obtained by BET, XRD, XPS, H-TPR and NH-TPD, the deactivation by CaO of CeO/TiO catalysts should be attributed to pore blockage, lower concentration of Ce on catalyst surface, reduction of Ce and surface adsorbed oxygen, degradation of redox ability and decrease in NH adsorption capacity. The theoretical DFT results demonstrated that Ca atom could strongly interact with cerium oxygen, which inhibits the formation and hydrogenation of oxygen vacancies on catalyst surface. [ABSTRACT FROM AUTHOR]

The compound {[Zn(μ-dicyanamide)(pyrazinamide)](pyrazinamide)} has been synthesized and further characterized by elemental analysis, single-crystal X-ray diffraction, and thermogravimetric analysis. Structural analysis revealed that the dicyanamide anion acted as bridging ligand in a μ-1,5 mode, resulting a polymeric 1-D chain structure. The pairwise N3-H3B···N1 and N9-H9B···N7, N3-H3A···O2 and N9-H9A···O1, N3-H3B···N7 and N9-H9B···N1 multiple hydrogen bonding interactions, impart enhanced stability to supramolecular structures. Hirshfeld surfaces and fingerprint plots were applied to arrive at the same conclusion, which is stabilised mainly by H-H, N-H, O-H interactions. DNA binding studies showed that the compound had interacted with DNA. [ABSTRACT FROM AUTHOR]

Tylototriton shanorum, an endemic species of Myanmar, is threatened by illegal capture and environmental destruction. Here, the complete mitochondrial genome (mitogenome) of T. shanorum is described. The entire mitogenome sequence of T. shanorum is 17,096 bp long, containing 13 protein coding genes, two ribosomal RNA, 22 transfer RNA genes, one control region. In addition, two additional 3′ Cytb like sequences and two complete tRNAThr genes, one pseudo tRNAThr, and three noncoding sequences (NC1, NC1′ and NC2) were situated between Cytb and tRNAPro genes. The new complete mitogenome sequence of T. shanorum will be useful for conservation genetics, evolutionary biology, phylogeography, as well as phylogenetic relationships studies of this threatened species. [ABSTRACT FROM AUTHOR]

Aluminum (Al)-induced apoptosis is considered as the major cause of its neurotoxicity. Folic acid possesses neuroprotective function by preventing neural cell apoptosis. microRNAs (miRNAs) are important regulators of gene expression participating in cellular processes. As a key component of the miR-17-92 cluster, miR-19 is implicated in regulating apoptotic process, while its role in the neuroprotective effect of folic acid has not been investigated. The present study aimed to investigate the potential involvement and function of miR-19 in the protective action of folic acid against Al-induced neural cell apoptosis. Human SH-SY5Y cells were treated with Al-maltolate (Al-malt) in the presence or absence of folic acid. Results showed that Al-malt-induced apoptosis of SH-SY5Y cells was effectively prevented by folic acid. Al-malt suppressed the expression of miR-19a/19b, along with alterations of miR-19 related apoptotic proteins including PTEN, p-AKT, p53, Bax, Bcl-2, caspase 9 and caspase 3; and these effects were ameliorated by folic acid. miR-19 inhibitor alone induced apoptosis of SH-SY5Y cells. Combination treatment of folic acid and miR-19 inhibitor diminished the neuroprotective effect of folic acid. These findings demonstrated that folic acid protected neuronal cells against Al-malt-induced apoptosis by preventing the downregulation of miR-19 and modulation of miR-19 related downstream PTEN/AKT/p53 pathway. [ABSTRACT FROM AUTHOR]

This study aimed to determine the factors that impact early cochlear implantation (CI) in Chinese children. The charts of 56 pediatric cochlear implant recipients were retrospectively reviewed. Parental interviews were conducted to collect information regarding the factors that potentially impact early CI in Chinese children. The mean age at CI was 40.98 months, and the median age was 24 months. Thirty patients received an implant before 24 months of age, and the other 26 patients received the implant after 24 months of age. By univariate logistic regression analysis, newborn hearing screening (NHS), financial burden impacted early CI significantly ( p < 0.05), while the multivariate analysis indicated that only NHS significantly influenced the early CI ( p < 0.05). The following factors were associated with a moderately increased risk of late implantation: lack of NHS [odds ratio (OR) = 5.833], living in a rural community (OR = 2.714), and communication barriers (OR = 2.691). Living in a rural community, financial burden and communication barriers negatively impact the age at CI, whereas NHS positively influence the age at CI. Increased awareness of these factors could promote early CI and improve the quality of life of congenitally deaf children. [ABSTRACT FROM AUTHOR]

To facilitate the pseudochromosomes assembly and gene cloning in rapeseed, we developed a reference genetic population/map (named BnaZNF2) from two sequenced cultivars, Zhongshuang11 and No.73290, those exhibit significant differences in many traits, particularly yield components. The BnaZNF2 genetic map exhibited perfect collinearity with the physical map of B. napus, indicating its high quality. Comparative mapping revealed several genomic rearrangements between B. napus and B. rapa or B. oleracea. A total of eight and 16 QTLs were identified for pod number and seed number per pod, respectively, and of which three and five QTLs are identical to previously identified ones, whereas the other five and 11 are novel. Two new major QTL respectively for pod number and seed number per pod, qPN.A06-1 and qSN.A06-1 (R² = 22.8% and 32.1%), were colocalised with opposite effects, and only qPN.A06-1 was confirmed and narrowed by regional association analysis to 180 kb including only 33 annotated genes. Conditional QTL analysis and subsequent NILs test indicated that tight linkage, rather than pleiotropy, was the genetic causation of their colocalisation. Our study demonstrates potential of this reference genetic population/map for precise QTL mapping and as a base for positional gene cloning in rapeseed. [ABSTRACT FROM AUTHOR]

The Oriental Fire-bellied Newt ( Cynops orientalis David) has been listed as Near Threatened species (NT) recently due to habitat destruction and degradation and illegal trade in the domestic and international pet markets. We sequenced and characterized the complete mitochondrial genome (mitogenome) of C. orientalis in this paper. The complete mitogenome sequence of C. orientalis is 16,294 bp in length, containing 37 genes (13 protein coding genes, two ribosomal RNA, 22 transfer RNA genes and one control region). The new sequenced complete mitogenome of C. orientalis will provide useful information for application in conservation genetics and evolution for this near threatened species. [ABSTRACT FROM AUTHOR]

Background: Gastric lymphoepithelioma-like carcinoma (LELC) is a rare entity that is closely associated with Epstein-Barr virus (EBV). However, the EBV latency pattern and genome polymorphisms in gastric LELC have not been systematically explored. Methods: The clinicopathological features, EBV latency pattern and genome polymorphisms of EBV-positive gastric LELC in Guangzhou, southern China were investigated and compared with those of ordinary EBV-associated gastric carcinoma (EBVaGC) in the same area. Results: Ten (1.42 %) of 702 gastric carcinoma cases were identified as gastric LELC, in which eight (80 %) cases were EBV-positive. The clinicopathological characteristics and EBV latency pattern of EBV-positive gastric LELC were similar to those of ordinary EBVaGC. In EBV genotype analysis, type A strain, type F, I, mut-W1/I, XhoI− and del-LMP1 variants were predominant among EBV-positive gastric LELCs, accounting for eight (100 %), six (75 %), eight (100 %), seven (87.5 %), five (62.5 %) and six (75 %) cases, respectively, which are similar to those in ordinary EBVaGC. For EBNA1 polymorphisms, the V-leu and P-ala subtypes were predominant in EBV-positive gastric LELC, which is different from the predominant V-val subtype in ordinary EBVaGC. EBV-positive gastric LELC has a favorable prognosis when compared to ordinary EBVaGC (median survival time 43.0 vs. 18.0 months). Conclusions: Gastric LELC is strongly associated with EBV and EBV-positive gastric LELC should be regarded as a special subtype of EBVaGC. This, to our best knowledge, is the first time in the world that the EBV latency pattern and genome polymorphisms of EBV-positive gastric LELC are systematically revealed. [ABSTRACT FROM AUTHOR]

Alterations in global DNA methylation and specific regulatory gene methylation are frequently found in cancer, but the significance of these epigenetic changes in EBV-associated gastric carcinoma (EBVaGC) remains unclear. We evaluated global DNA methylation status in 49 EBVaGC and 45 EBV-negative gastric carcinoma (EBVnGC) tissue samples and cell lines by 5-methylcytosine immunohistochemical staining and methylation quantification. We determined promoter methylation status and protein expression for the p16, FHIT, CRBP1, WWOX, and DLC- 1 genes in tissues and studied the correlation between CpG island methylator phenotype (CIMP) class and clinicopathological characteristics. Changes in gene methylation and mRNA expression in EBVaGC cell line SNU-719 and in EBVnGC cell lines SGC-7901, BGC-823, and AGS were assessed after treatment with 5-aza-2′-deoxycytidine (5-aza-dC), trichostatin A (TSA), or a combination of both, by methylation-specific PCR and quantitative real-time RT-PCR. Global genomic DNA hypomethylation was more pronounced in EBVnGC than in EBVaGC. Promoter methylation of all five genes was more frequent in EBVaGC than in EBVnGC ( p < 0.05). p16 and FHIT methylation was reversely correlated with protein expression in EBVaGC. Most (41/49) EBVaGC exhibited CIMP-high (CIMP-H), and the prognosis of CIMP-H patients was significantly worse than that of CIMP-low ( p = 0.027) and CIMP-none ( p = 0.003) patients. Treatment with 5-aza-dC and/or TSA induced upregulation of RNA expression of all five genes in SNU-719; meanwhile, individual gene expression increased in EBVnGC cell lines. In summary, EBV-induced hypermethylation of p16, FHIT, CRBP1, WWOX, and DLC- 1 may contribute to EBVaGC development. Demethylation therapy may represent a novel therapeutic strategy for EBVaGC. [ABSTRACT FROM AUTHOR]

In this paper, large area multi-crystalline silicon (mc-Si) solar cells of 156 mm × 156 mm were fabricated by the combination of Ag-assisted etching and sodium hydroxide (NaOH) treatment. Scanning electron microscope, UV-Vis-NIR spectrophotometer, external quantum efficiency measurement system, and current-voltage test were used to characterize the etched black silicon wafers and the fabricated solar cells. It was found that, though the black mc-Si without NaOH treatment showed a lowest reflectance of 2.03 % in the wavelength of 400-900 nm, the maximum conversion efficiency came from the mc-Si solar cells produced by combination of Ag-assisted etching and NaOH treatment. Though the solar cell with additional NaOH treatment for 30 s presented a reflectance of 5.45 %, it presented the highest conversion efficiency of 18.03 %, which is 0.64 % higher than the traditional mc-Si solar cell (17.39 %) and much higher than that of the black mc-Si solar cell without NaOH treatment (16.24 %). [ABSTRACT FROM AUTHOR]

In this paper, nickel nanoparticles (Ni NPs) were deposited on planar silicon and pyramidal silicon wafers by the magnetron sputtering method, and then these Ni NP-covered samples were etched in a hydrofluoric acid, hydrogen peroxide, and deionized water mixed solution at room temperature to fabricate a low reflective silicon surface. An alumina (AlO) film was then deposited on the surface of the as-etched pyramidal sample by atomic layer deposition to further reduce the reflectance. The morphologies and compositions of these samples were studied by using a field emission scanning electron microscope attached to an energy-dispersive X-ray spectrometer. The surface reflectance measurements were carried out with a UV-Vis-NIR spectrophotometer in a wavelength range of 200-1100 nm. The SEM images show that the as-etched planar and pyramidal silicon samples were covered with many rhombic nanostructures and that some nanostructures on the planar silicon surface were ready to exhibit a flower-like burst. The reflectances of the as-etched planar and pyramidal silicon samples were 5.22 % and 3.21 % in the wavelength range of 400-800 nm, respectively. After being coated with a 75-nm-thick AlO film, the etched pyramidal silicon sample showed an even lower reflectance of 2.37 % from 400 nm to 800 nm. [ABSTRACT FROM AUTHOR]

Instead of noble metal like Pt, Au and Ag, cheap Ni nanoparticles (Ni NPs) were used to fabricate silicon nanostructures. Ni was found to be etched off during the etching process, while forming silicon nanostructures with very low reflectance of 1.59 % from 400 to 900 nm. The formation mechanism of silicon nanostructures by Ni-assisted etching was presented from the point of view of the low electronegativity of Ni. The Ni NPs were found being etched off during the assisted etching process, which implies that the transfer rate of electrons from Si to Ni is slower than that from Ni to O in the case of using Ni as assisted metal. The reason of sparser and deeper silicon nanostructures etched in lower HO concentration solution is that the Ni NPs can be lasted for longer time in the etching solution with lower HO concentration so that more silicon atoms will be oxidized and then removed for those under Ni NPs due to the hole transfer and those where uncovered by Ni NPs due to the hole diffusion. [ABSTRACT FROM AUTHOR]

Further investigation into the methods for the analysis of the entrapment efficiency of liposomes has been prompted by the urgent need to improve traditional methods which offer more risk to liposome leakage. The aim of this study was to investigate the suitability of hollow fiber centrifugal ultrafiltration (HF-CF-UF) coupled with HPLC as an alternative method for the routine determination of the entrapment efficiency of liposomes and to compare it with previously developed nonequilibrium procedures based on size-exclusion chromatography (SEC). By comparison, evaluation of the entrapped fraction with SEC resulted in 3 or 4 % lower entrapment values. More importantly, the free drug concentrations were three- to sixfold higher than with HF-CF-UF. In addition, we investigated the reasons for the different values obtained with SEC and a dynamic equilibrium theory was put forward based on this. In addition, we have developed and characterized an equilibrium method of separating free and liposomal drugs for liposomal formulations based on HF-CF-UF. The method was validated over the concentration range of 7.9-235 μg mL for indomethacin and 0.258-8.24 μg mL for vitamin A. Inter- and intra-day precision (RSD %) were ≤1.2 % for indomethacin and ≤1.8 % for vitamin A, respectively. The recoveries of both free drug and total drug were higher than 96.0 % with RSD ≤1.3 % ( n = 5). Taken together, our improved method differs from those previously reported with regard to higher recovery, small sample volume, less laborious, and most importantly without damaging or disturbing liposomes. Validation results suggested that our method was sufficiently accurate and sensitive to be used to evaluate the entrapment efficiency of a liposome formulation without complicated pretreatment. [ABSTRACT FROM AUTHOR]

Aim:To investigate the effects of a new derivative of bisphosphonates, [2-(6-aminopurine-9-yl)-1-hydroxy-phosphine acyl ethyl] phosphonic acid (CP), on human gastric cancer.Methods:Human gastric cancer cell lines (SGC-7901, BGC-823, MKN-45, and MKN-28) and human colon carcinoma cell lines (LoVo and HT-29) were tested. Cell growth was determined using the MTT assay. Flow cytometry, Western blot, caspase activity assay and siRNA transfection were used to examine the mechanisms of anticancer action. Female BALB/c nude mice were implanted with SGC-7901 cells. From d6 after inoculation, the animals were injected with CP (200 μg/kg, ip) or vehicle daily for 24 d.Results:CP suppressed the growth of the 6 human cancer cell lines with similar IC50 values (3239 μmol/L). In SGC-7901 cells, CP arrested cell cycle progression at the G2/M phase. The compound activated caspase-9, increased the expression of pro-apoptotic proteins Bax and Bad, decreased the expression of anti-apoptotic protein Bcl-2. Furthermore, the compound selectively activated ERK1/2 without affecting JNK and p38 in SGC-7901 cells. Treatment of SGC-7901 cells with the specific ERK1/2 inhibitor PD98059 or ERK1/2 siRNA hampered CP-mediated apoptosis. In the human gastric cancer xenograft nude mouse model, chronic administration of CP significantly retarded the tumor growth.Conclusion:CP is a broad-spectrum inhibitor of human carcinoma cells in vitro, and it also exerts significant inhibition on gastric cancer cell growth in vivo. CP induces human gastric cancer apoptosis via activation of the ERK1/2 signaling pathway. [ABSTRACT FROM AUTHOR]