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The ability of water mist to mitigate blast loads has been widely recognized. However, the effects of the mean droplet diameter and volume fraction of water mist on the blast mitigation effect and underlying mechanisms have not been comprehensively examined. In this study, a three-dimensional numerical simulation based on the Euler-Lagrangian approach was carried out to study the dissipation process of blast wave energy and momentum by water mist, as well as the impact of varying mean droplet diameters (255-855 μm) and volume fractions (2.4x10-3-5.4x10-3) on blast mitigation. The numerical model incorporates interphase mass, momentum, and energy exchanges, as well as droplet breakup and size distribution. The results showed that the most efficient transfer of momentum and energy between the blast wave and water mist occurred at the air/water mist interface. Subsequently, the efficiency of momentum and energy transfer decreased as the blast wave propagated within the water mist due to the blast wave mitigation. The reduction in the mean droplet diameter and the increase in the volume fraction result in an increase in both the total the surface area and number of water droplets, thereby enhancing the efficiency of energy and momentum absorption by droplets and improving their ability to mitigate blasts. [ABSTRACT FROM AUTHOR]

"Desalted water" feedwater oxygen treatment dexterously combines the characteristics of water vapor loss in normal operation of unit and the natural saturation of dissolved oxygen in make-up water. It's a new way to implement oxygenated treatment of boiler feedwater, which is more environmentally friendly and economical. Compared to the conventional oxygen bottles or air oxygen methods, the passivation protection mechanism of the heating surface has no difference in essence, but it's further improved in the aspects of simple operation, project investment and cost, and reduce the use of dangerous chemical sources. A 350 MW supercritical unit applied this technology in China, after nearly 2 y operation, the cleanliness of the water vapor system and the stability control of dissolved oxygen has achieved successful results. According to operation statistics, the new technology has saved more than 2 million RMB of economic cost for the power plant, and gradually applied in Henan, Guizhou, Hubei, Inner Mongolia and other regions. [ABSTRACT FROM AUTHOR]

To analyse the spatial distribution patterns and sources of heavy metals (Cr, Cu, Ni, Zn), 25 road dust samples were collected from a typical industrial area of Wuhan in July 2017. The multivariate statistics, geostatistics, and the field source survey were adopted to study the sources and pollution pattern of studied metals. The results indicated that the concentration distribution of heavy metals was related to dust particle size and pollution source. Cr had high spatial aggregation in QD, could be concentrated easily in 63-150 µm dust, and was discharged by industrial sources. Cu, Zn, and Ni were also enriched in 63-150 µm dust. Cu had high spatial aggregation in less than 45 µm and was derived from building construction sources. Zn and Ni were concentrated in 63-150 µm and originated from traffic sources and building construction sources. Pollution source influenced particle size and the content and distribution pattern of different heavy metals in atmospheric sediments, but the influence had obvious spatial limitations and compound effects. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To investigate the influences of rapamycin on proliferation and apoptosis of human osteosarcoma MG-63 cells and the mechanisms of action. MATERIALS AND METHODS: The human osteosarcoma MG-63 cells were randomly divided into Control group, Rapamycin group, and Rapamycin + Beclin-1 plasmid transfection group. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was adopted to detect the viability of MG-63 cells in each group, and the 5-Ethynyl-2'-deoxyuridine (EdU) staining and Hoechst staining were applied to determine the proliferation and apoptosis, respectively, of MG-63 cells in each group. The levels of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax) were measured using enzyme-linked immunosorbent assay (ELISA) kits, and the protein expression levels of Beclin-1 and Vps34 in each group of MG-63 cells were tested using the Western blotting. RESULTS: Compared with the Control group, Rapamycin group, and Rapamycin + Beclin-1 plasmid transfection group had markedly weakened the viability of MG-63 cells, inhibited cell proliferation, remarkably increased cell apoptosis rate, elevated Bax level, notably declined Bcl-2 level, and significantly raised the levels of Beclin-1 and Vps34 proteins in MG-63 cells. Besides, the effects in Beclin-1 plasmid transfection group were stronger. CONCLUSIONS: Rapamycin may decrease the viability, inhibit the proliferation, and promote the apoptosis of MG-63 cells by activating autophagy. [ABSTRACT FROM AUTHOR]

In2O3 is a promising partner of Cu2O to form a Cu2O/In2O3 heterojunction system. We used x-ray photoelectron spectroscopy to determine the valence band offset (VBO) of a Cu2O/In2O3 heterojunction. The valence band offset is found to be 1.43 ± 0.2 eV. Given the experimental bandgaps of 2.0 eV and 2.6 eV for Cu2O and In2O3, respectively, we calculate the band alignment of a Cu2O/In2O3 heterojunction with a conduction band offset (CBO) of 0.83 ± 0.2 eV. To apply Cu2O/In2O3 bilayers in electronic devices, it is important to determine the band alignment accurately based on the VBO and CBO. [ABSTRACT FROM AUTHOR]

We investigate the field electron emission for amorphous carbon (a-C) films deposited on Si (100) substrates through a niobium carbide buffer layer at different flow rate ratios of CH4/(CH4+Ar) in a CH4/Ar mixture discharge, and find that the composition and chemical bonding of the buffer layer can substantially affect the electron field emission properties of a-C films. The high ratio of Nb–C/Nb–Nb bonds in the buffer layer promotes the electron emission of a-C film. The first-principles calculated results show that the work function of NbC is lower than that of Nb, which is the reason why the high ratio of Nb–C/Nb–Nb bonds in the buffer layer favors the field emission of a-C film. [ABSTRACT FROM AUTHOR]

We investigate the field electron emission for amorphous carbon (a-C) films deposited on Si (100) substrates through a niobium carbide buffer layer with different structures and find that the niobium carbide buffer layer can substantially improve the electron field emission properties of a-C films, which can be attributed to an increase in the enhancement factor β on the surface of a-C films after the insertion of the niobium carbide layer in between a-C film and substrate. Moreover, a phase transition for niobium carbide layer from hexagonal (Nb2C) to cubic (NbC) structure, revealed by x-ray diffraction, further enhances the electron field emission. The first-principles calculated results show that the work function of NbC is lower than that of Nb2C, which is the reason why the electron emission of a-C is further enhanced. [ABSTRACT FROM AUTHOR]

Field electron emission for amorphous carbon (a-C) films deposited on Si (100) substrates with a niobium buffer layer is investigated. It is found that the Nb buffer layer can substantially improve the electron field emission properties of the a-C films, which can be attributed to an increase in the enhancement factor β on the surface of the a-C films after insertion of the Nb layer. Moreover, the electron field emission can be further enhanced by annealing a-C/Nb/Si, which can be ascribed to the formation of NbC phase at the interface between a-C and Nb layer, revealed by x-ray diffraction for annealed a-C/Nb/Si. The first-principles calculated results show that the formation of NbC can lower the interface barrier and improve the back contact between Nb and a-C films, enhancing the field electron emission of a-C. [ABSTRACT FROM AUTHOR]

Summary: Dietary patterns may interfere with the efficacy of herbal intervention. Our results demonstrated the protective effects of Salvia miltiorrhiza aqueous extract (SMA) on bone metabolism were influenced by levels of dietary fat and sucrose in ovariectomized (OVX) rats through its actions on attenuating lipid deposition and oxidative stress in rats. Introduction: Salvia miltiorrhiza (SM), also known as Danshen, has been tested as an osteoporosis treatment in a series of small, short human trials that generally report improvements in bone property. However, dietary patterns may interfere with the effects of herbal intervention. We hypothesized that dietary fat and sucrose levels could influence the effects of SM supplementation on bone in estrogen-deficient animals. Methods: Six-month-old Sprague-Dawley sham or OVX rats were fed either a low-saturated fat-sucrose (LFS, a diet that was similar in composition to normal rat chow) or a high-fat-sucrose (HFS) diet and OVX rats were treated (8 rats/group) with SM aqueous extract (SMA, 600 mg/kg/day), 17β-estradiol (1 mg/kg/day), or vehicle for 12 weeks. Results: SMA significantly improved bone properties as revealed by the increase in trabecular bone mineral density and decrease in trabecular separation at proximal metaphysis of the tibia (PT) in HFS-fed OVX rats, but not in LFS-fed OVX rats. SMA greatly reduced lipid deposition and malondialdehyde levels, improved the activities of superoxide dismutase, catalase, and glutathione peroxidase in the livers of HFS-fed OVX rats. SMA could directly improve the proliferation and differentiation in vitro in an HO-induced preosteoblast cell model by attenuating cellular reactive oxygen species levels. Conclusions: The protective effects of SMA on bone metabolism were influenced by dietary fat and sucrose levels in OVX rats. The ability of SMA to reduce bone loss in HFS-fed OVX rats was associated with the attenuation of lipid deposition and oxidative stress levels. [ABSTRACT FROM AUTHOR]

[Fe/Pt]n multilayer films were prepared on thermally oxidized Si (100) substrates at 300°C using dc magnetron sputtering and annealed for different temperature ranging from 350 to 500°C. It is found that the as-deposited [Fe/Pt]n multilayer films exhibit well-resolved periodic structures and low roughness of interface. The ordering degree of the annealed films decreases and their perpendicular magnetic anisotropy deteriorates with increasing the period number. Fe/Pt bilayer film annealed at 350°C shows (001) orientation and hard magnetic characteristic, the coercivity and perpendicular anisotropy enhance with increase of annealing temperature. In addition, the hard and soft magnetic phases are not fully magnetically coupled in the Fe/Pt film annealed at higher temperature. [ABSTRACT FROM AUTHOR]

Titanium-doped indium oxide (In2O3) transparent conductive thin films were deposited on glass and sapphire (0001) substrates with/without oxygen atmosphere by DC magnetron sputtering at 300 °C. The content of titanium is estimated to be about 1.8 at.% using energy dispersive spectroscopy. The smooth surfaces were covered with more uniform octahedral grains. X-ray diffraction measurements indicated that the preferential growth orientation along the (400) plane for the sample grown without oxygen atmosphere shifts to (222) for the sample grown in the oxygen atmosphere. The average optical transmittance of the sample grown with the introduction of oxygen varies from 70% to 90% in the visible region, which corresponds well to the variation of carrier and mobility. Hence, both intermediate dopant and oxygen atmosphere will provide the optimum balance between carrier concentration and mobility leading to the best transport properties of Ti-doped In2O3 films. [ABSTRACT FROM AUTHOR]

The structures of BaTiO[sub 3] thin films and BaTiO[sub 3]/YBa[sub 2]Cu[sub 3]O[sub 7-δ] bilayer films grown on SrTiO[sub 3] and LaAlO[sub 3] substrates, respectively by pulsed laser deposition, have been investigated by X-ray triple-axis diffraction. The orientation, the interface mismatch and strain status, and the in-plane and perpendicular lattice constants of the epilayers have been determined by reciprocal space map analysis. The results show that both the lattice constants and the structural imperfections of the BaTiO[sub 3] layers are relevant to the oxygen partial pressure. The a[sub ⊥]/a... increases while the full width at half maximum (FWHM) of the rocking curves decreases with the decrease in the partial oxygen pressure. [ABSTRACT FROM AUTHOR]

This paper describes a low-cost soft-lithography method for building large-numerical-aperture microlenses in hybrid sol-gel glass. The fabrication processes comprise three steps, namely fabrication of large numerical aperture microlens array in photoresist as a master, replication of the master in poly-dimethylsiloxane (PDMS) as elastomeric molds and reproduction of the PDMS replica onto the hybrid sol-gel glass as an end structure. Comparing with the direct UV fabrication in the photosensitive sol-gel glass, the proposed method provides a unique advantage in terms of fabrication freedom in shape and thickness of micro-optical elements in the sol-gel glass. This eliminates the difficulties in direct photolithography in sol-gel glass for arbitrary shapes and great thickness due to ever increasing demands. [ABSTRACT FROM AUTHOR]

Objective: Brain and muscle ARNT-like protein 1 (BMAL1) is a core component of hepatocyte molecular clock and plays an important role in the regulation of other related rhythmic genes in the body through a transcriptional-translational feedback loop in molecular circadian oscillations. Therefore, the aim of this study was to investigate the role of BMAL1 in the rat periodontitis-induced liver injury. Methods: Twelve male Wistar rats were divided into the control group and the periodontitis group according to the random number table method. The rats in the control group were untreated. The periodontitis models were established by ligating the necks of the bilateral maxillary first molars in the periodontitis group rats. After 8 weeks, periodontal clinical indexes of rats in both groups were examined and executed. Micro-CT scans of the maxilla were performed and levels of the alveolar bone resorption were analyzed. Pathological changes in periodontal and liver tissue of rats in two groups were detected by HE and oil red O staining. Biochemical kits were used to detect glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), total cholesterol (TC) and triglycerides (TG) in serum. The gene and protein expression levels of BMAL1, nuclear factor kappa-B (NF-κB) and tumor necrosis factor-α (TNF-α) in liver tissue were measured by real time fluorescent quantitative-PCR (qRT-PCR), immunohistochemistry (IHC) and Western blotting (WB) assays. Apoptosis was detected in liver tissues by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) kit staining. Results: The results of HE staining of maxillary first molars and micro-CT results of maxillary bones showed that alveolar bone resorption was significant in the periodontitis group of rats. The liver histopathology results showed infiltrated inflammatory cells in the liver tissue, disorganized liver cords and a large number of lipid droplets formed in the hepatocytes of the periodontitis group compared with the control group. The results of serum biochemical assay showed that the levels of GOT [(62.77±2.59) U/L], GPT [(47.54±1.04) U/L], TC [(3.19±0.23) mmol/L] and TG [(1.11±0.09) mmol/L] in the serum of rats with periodontitis were significantly higher than that in the control group respectively [GOT: (38.66±2.47) U/L, GPT: (31.48±1.57) U/L, TC: (1.60±0.05) mmol/L and TG: (0.61±0.09) mmol/L]( P= 0.003, P= 0.001, P= 0.002, P= 0.038). qRT-PCR results showed that the mRNA expression level of BMAL1 was significantly decreased in liver tissue of the periodontitis group [(0.60±0.04)%] compared to the control group [(1.01±0.07)%] ( t= 4.80, P= 0.009), while the mRNA expression levels of NF-κB and TNF-α [(1.62±0.12)%, (2.69±0.16)%] were significantly increased compared to the control group [(1.00±0.03)%, (1.03±0.16)%] ( P= 0.008, P= 0.002); IHC results showed that the protein expression level of BMAL1 in liver tissue of the periodontitis group (averaged optical density, AOD) (11.58±2.15) was down-regulated compared to the control group (AOD) (22.66±1.67) ( P= 0.015), while NF-κB and TNF-α (AOD) (31.77±2.69, 24.31±2.32) were up-regulated compared to the control group (AOD) (19.40±1.82, 11.92±0.94) ( P= 0.019, P= 0.008). WB results showed that the protein expression level of BMAL1 in liver tissue was down-regulated in the periodontitis group [(0.63±0.10)%] compared to the control group [(1.00±0.06)%] ( t= 3.19, P= 0.033), while NF-κB and TNF-α [(1.61±0.12)%, (2.82±0.23)%] were up-regulated compared to the control group [(1.00±0.12)%, (1.00±0.11)%] ( P= 0.022, P= 0.002). TUNEL staining showed increased apoptotic cells in the liver tissue of the periodontitis group of rats compared to the control group. Conclusions: Periodontitis may induce liver injury by down-regulating the BMAL1 expression levels in liver tissue, which in turn activates NF-κB signaling molecules, leading to the elevated levels of inflammation and apoptosis in rat liver.

Objectives: To investigate the prevalence and associated risk factors of tinnitus in Sichuan and Chongqing. Methods: We designed a tinnitus epidemiological questionnaire. The multi-stage stratified cluster random sampling methods was applied to obtain study subjects in six areas (Nanchong, Jiangjin, Fengdu, Yunyang, Suining and Ya'an), which were selected for epidemiological investigation. Home visit completion of epidemiological questionnaires was conducted. The trained investigators guided the respondents to fill in the tinnitus epidemiological questionnaires, and the epidemiological status of six areas on prevalence and risk factor was investigated. SPSS 22.0 software was used for statistical analysis. Results: Sampling population were 10 289, in which 9 273 were valid questionnaires. There were 4 281 males and 4 992 females, with an average age of 47.3 years, among which 34.83% (3 230/9 273) had tinnitus. 3.99% (370/9 273) were diagnosed with bothersome tinnitus. In a multivariable logistic regression mod, the following factors were associated with onsetting of tinnitus: sleep disorder [Odds Ratio( OR )=3.74] and noise exposure( OR =1.99). The risk of disease was lowest in the age of 30-40 years old, while the risk of disease was higher for people under 30 and over 40. In another multivariable logistic regression mode, the following factors were associated with having bothersome tinnitus: older people were more likely to suffer from tinnitus, sleep disorders ( OR =4.68) and noise exposure ( OR =1.56). Conclusions: The prevalence of tinnitus in Sichuan and Chongqing is about 34.83%, but most of the tinnitus is short-lived and has low loudness, which will not affect the patients. Only a small number of patients with tinnitus (3.99%) persist and affect their health and need treatment. The occurrence and exacerbation of tinnitus may be related to sleep, age, and noise exposure.