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  • Author: Tao Wen x
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Abstract

A ceria loaded carbon nanotubes (CeO2/CNTs) nanocomposites photocatalyst was prepared by chemical precipitation, and the preparation conditions were optimized using an orthogonal experiment method. HR-TEM, XRD, UV-Vis/DRS, TGA and XPS were used to characterize the photocatalyst. Nitrogen adsorption-desorption was employed to determine the BET specific surface area. The results indicated that the photocatalyst has no obvious impurities. CeO2 was dispersed on the carbon nanotubes with a good loading effect and high loading efficiency without agglomeration. The catalyst exhibits a strong ability to absorb light in the ultraviolet region and some ability to absorb light in the visible light region. The CeO2/CNTs nanocomposites photocatalyst was used to degrade azo dye Acid Orange 7 (40 mg/L). The optical decolorization rate was 66.58% after xenon lamp irradiation for 4 h, which is better than that of commercial CeO2 (43.13%). The results suggested that CeO2 loading on CNTs not only enhanced the optical decolorization rate but also accelerated the separation of CeO2/CNTs and water.

Abstract

A facility of BaPS (Barometric Process Separation) and indoor incubation experiments were used to determine the effect of soil salinity on soil respiration and nitrogen transformation. The rates of soil respiration, gross nitrification, denitrification, ammonium and nitrate nitrogen concentrations and relevant soil parameters were measured. Results showed that soil respiration and nitrification and denitrification rates were all affected by soil salinity. Furthermore, the effect of soil salinity level on nitrification and denitrification rates had a threshold value (EC1:5 = 1.13 dS/m). When soil salinity level was smaller to this threshold value, the rates of nitrification and denitrification increased with soil salinity while they were reduced when soil salinity level was larger than the threshold value. Moreover, the changing law of soil respiration rate with soil salinity was similar with the nitrification and denitrification rates while the variation tendency was opposite. In addition, the transformation form urea to ammonium and nitrate nitrogen was also reduced with the increase of soil salinity and the reduced effect could be expressed by exponential functions.

Abstract

Soil nitrogen transportation and transformation are important processes for crop growth and environmental protection, and they are influenced by various environmental factors and human interventions. This study aims to determine the effects of irrigation and soil salinity levels on nitrogen transportation and transformation using two types of experiments: column and incubation. The HYDRUS-1D model and an empirical model were used to simulate the nitrogen transportation and transformation processes. HYDRUS-1D performed well in the simulation of nitrogen transportation and transformation under irrigated conditions (R 2 as high as 0.944 and 0.763 for ammonium and nitrate-nitrogen simulations, respectively). In addition, the empirical model was able to attain accurate estimations for ammonium (R 2 = 0.512-0.977) and nitrate-nitrogen (R 2 = 0.410-0.679) without irrigation. The modelling results indicated that saline soil reduced the rate of urea hydrolysis to ammonium, promoted the longitudinal dispersity of nitrogen and enhanced the adsorption of ammonium-nitrogen. Furthermore, the effects of soil salinity on the nitrification rate were not obviously comparable to the effects of the amount of irrigation water. Without irrigation, the hydrolysis rate of urea to ammonium decreased exponentially with the soil salinity (R 2 = 0.787), although the nitrification coefficient varied with salinity. However, the denitrification coefficient increased linearly with salinity (R 2 = 0.499).

Abstract

Objective A diagnostic model was established to discriminate infectious diseases from non-infectious diseases.

Methods The clinical data of patients with fever of unknown origin (FUO) hospitalized in Xiangya Hospital Central South University, from January, 2006 to April, 2011 were retrospectively analyzed. Patients enrolled were divided into two groups. The first group was used to develop a diagnostic model: independent variables were recorded and considered in a logistic regression analysis to identify infectious and non-infectious diseases (αin = 0.05, αout = 0.10). The second group was used to evaluate the diagnostic model and make ROC analysis.

Results The diagnostic rate of 143 patients in the first group was 87.4%, the diagnosis included infectious disease (52.4%), connective tissue diseases (16.8%), neoplastic disease (16.1%) and miscellaneous (2.1%). The diagnostic rate of 168 patients in the second group was 88.4%, and the diagnosis was similar to the first group. Logistic regression analysis showed that decreased white blood cell count (WBC < 4.0×109/L), higher lactate dehydrogenase level (LDH > 320 U/L) and lymphadenectasis were independent risk factors associated with non-infectious diseases. The odds ratios were 14.74, 5.84 and 5.11 (P ≤ 0.01) , respectively. In ROC analysis, the sensitivity and specificity of the positive predictive values was 62.1% and 89.1%, respectively, while that of negative predicting values were 75% and 81.7%, respectively (AUC = 0.76, P = 0.00).

Conclusions The combination of WBC < 4.0×109/L, LDH > 320 U/L and lymphadenectasis may be useful in discriminating infectious diseases from non-infectious diseases in patients hospitalized as FUO.

Abstract

Background: Rocuronium is an alternative to succinylcholine for rapid tracheal intubation after major thermal injury and other forms of critical illness that cause denervation changes in skeletal muscle. Rocuronium may decrease the potencies of non-depolarizing muscle relaxants.

Objectives: Examine whether potency of rocuronium changed during the first month after denervation, and investigate the effects of skeletal muscle denervation on potency of rocuronium.

Methods: The denervation mouse model was developed to create denervated individual cells from the flexor digitorum brevis of the hindfoot. The skeletal muscle cells were examined at day 0 in the innervated control and days 1, 4, 7, 14, 21, and 28 in the denervation group. Nicotinic acetylcholine receptors in the cells were activated with 30 M acetylcholine, alone or in combination with various concentrations of rocuronium. Currents were recorded with a whole-cell patch-clamp technique.

Results: Rocuronium reversibly inhibited acetylcholine-activated currents in a dose-dependent fashion at different times after denervation. The inhibition concentration for the half-maximal responses of rocuronium increased 1.2- (p >0.05), 1.8-, 2.8-, 2.3-, 2.1-, and 1.9-fold (p <0.01) at day 1, 4, 7, 14, 21, and 28 after denervation, respectively, compared to that at day 0 after denervation.

Conclusion: Rocuronium dose required to achieve satisfactory clinical effects changed at different durations after skeletal muscle denervation.

Abstract

For improving the understanding of interactions between hyperspectral reflectance and soil salinity, in situ hyperspectral inversion of soil salt content at a depth of 0-10 cm was conducted in Hetao Irrigation District, Inner Mongolia, China. Six filtering methods were used to preprocess soil reflectance data, and waveband selection combined by VIP (variable importance in projection) and b-coefficients (regression coefficients of model) was also applied to simplify model. Then statistical methods of partial least square regression (PLS) and orthogonal projection to latent structures (OPLS) were processed to establish the inversion models. Our findings indicate that the selected sensitive wavebands for the 6 filtering methods are different, among which the multiplicative signal correction (MSC) and standard normal variate methods (SNV) have some similar sensitive wavebands with unfiltered data. Derivatives (DF1 and DF2) could characterize sensitive wavebands along the scale of VNIR (350-1100 nm), especially the second derivative (DF2). The sensitive wavebands for continuum-removed reflectance method (CR) have protruded many narrow absorption features. For orthogonal signal correction method (OSC), the selected wavebands are centralized in the range of 565-1013 nm. The calibration and evaluation processes have demonstrated the second order derivate filtering method (DF2) combined with waveband selection is superior to other processes, for it has high R 2 (larger than 0.7) both in PLS and OPLS models for calibration and evaluation, by choosing only 156 wavebands from the whole 700 wavebands. Meanwhile, OPLS method was considered to be more suitable for the analyzing than PLS in most of our situations.

Summary

Conditioning is a very important procedure for tobacco and tobacco products before their corresponding chemical and physical analysis. For cigarettes, forced air flow is generally required during the conditioning procedure. A special wind tunnel was designed to investigate how the forced air flow affects the conditioning of cigarettes in a constant climate laboratory. Two types of cigarettes with blended (including flue-cured and burley tobacco strands) and pure flue-cured tobacco strands were selected as test samples. It was found that the conditioning time to achieve the equilibrium could be shortened from 23 h without forced air flow to 7 h with a forced air flow rate of 2m/s. This is mainly due to the exchange of water molecules between cigarette samples and atmosphere being accelerated by applying the forced air flow. It was concluded that a 48 h conditioning period using the described forced air flow rate setup was unnecessary to attain the equilibrium for cigarettes. [Beitr. Tabakforsch. Int. 28 (2019) 224–229]

Abstract

Introduction: The extremely high genetic variation and the continuously emerging variants of foot-and-mouth disease virus (FMDV) of Southern African Territory (SAT) serotypes including SAT1, SAT2, and SAT3 make it necessary to develop a new RT-PCR for general use for monitoring viruses based on the updated genome information.

Material and Methods: A FMDV SAT-D8 one-step RT-PCR was established based on the 1D2A2B genes of the SAT serotype viruses with a multiplex primer set. FMDV A, O, C, and Asia 1 serotypes, other vesicular disease viruses, inactivated SAT viruses, and 125 bovine, ovine, caprine and porcine tissue samples collected from the Chinese mainland were included for evaluating the assay.

Results: The new RT-PCR was proven to be specific without cross-reactions with Eurasian FMDV, swine vesicular disease virus (SVDV), Seneca valley virus (SVV), or other common viral pathogens of cattle, sheep, goat, and pig. An around 257 bp-sized amplicon clearly appeared when the inactivated SAT viruses were detected. However, all 125 samples collected from FMDV-susceptible animals from the Chinese mainland which has not known SAT epidemics showed negative results.

Conclusions: A FMDV SAT-D8 one-step RT-PCR is a promising method for primary screening for FMDV SAT serotypes.

Objective To evaluate the efficacy and safety of traditional Chinese medicine (TCM) combined with Western medicine in the treatment of patients with common hand, foot and mouth disease (HFMD) by conducting a prospective, controlled, and randomized trial.

Methods A total of 452 patients with common HFMD were randomly assigned to receive Western medicine alone (n = 220) or combined with TCM (Reduning or Xiyanping injections) (n = 232). The primary outcome was the incidence rate of rash/herpes disappearance within 5 days, while secondary outcomes included the incidence rate for fever, cough, lethargy, agitation, and vomiting clearance within 5 days.

Results The rash/herpes disappearance rate was 45.5% (100/220) in Western medicine therapy group, and 67.2% (156/232) in TCM and Western medicine combined therapy group, with significant difference (P < 0.001). Moreover, TCM remarkably increased the incidence rate of secondary disappearance, which was 56.4% in Western medicine therapy group and 71.4% in TCM and Western medicine combined therapy group (P = 0.001). No drug-related adverse events were observed.

Conclusions It’s suggested that the integrative TCM and Western medicine therapy achieved a better therapeutic efficacy. TCM may become an important complementary therapy on relieving the symptoms of HFMD.