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To study the preparation of ultra-early strength grouting material without external early-strength additives to meet the 6 h compressive strength of not less than 30 MPa, sulfur-aluminate cement (SAC) was used to replace part of the ordinary Portland cement, and the optimal content of SAC was explored. On this basis, the one-factor test and orthogonal test of silica fume, microbeads and redispersible emulsion powder were carried out to study the effects on the fluidity, and physical properties of ultraearly strength grouting material, as well as SEM micro-mechanism analysis. The test results show that; with the increase of SAC doping, the flexural and compressive strength of ultra-early strength grouting material were first increased and then decreased, and the optimal doping is 35%; on this basis, single doping of silica fume, microbeads and redispersible emulsion powder, the flexural and compressive strength of ultra-early strength grouting material were first increased and then decreased, with the optimal doping of silica fume at 7.5%, the optimal doping of microbeads at 1%, and the optimal doping of redispersible emulsion powder at 1%. For the orthogonal test of silica fume, microbeads and redispersible emulsion powder, the optimal content of the three is 5%, 5% and 0.5%, respectively; through SEM characterization of microscopic features, when hydrated for 6 h, the cementitious material also has high densification and compactness, which meet the compressive strength requirement of 30 MPa. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the heavy metal enrichment and spatial distribution characteristics of plants around tailings ponds in typical karst areas, and to screen the dominant plant varieties. Method: The enrichment coefficient was calculated to determine the enrichment ability of different plants to different heavy metals. The spatial distribution model of plant heavy metals was established utilizing general Kriging interpolation and semi-variance function analysis using geographic information analysis software (GIS) . The Pearson correlation coefficient was calculated to analyze the correlation between various heavy metals in plants and soil pH value. Result: Among the 28 plants around the tailings pond, Peristrophe roxburghiana of Solanaceae, Gynura crepidioides of Compositae, and Boehmeria tricuspis of Nettle family had strong enrichment ability of Cd, and Cd pollution was serious in plants. Lyginodendron oldhamium Potonie of Blechnaceae, Bridelia insulana of Kuphorbiaceae had strong enrichment capacity for Pb. There was no enrichment of Cu and Zn in all plants. The spatial distribution model of heavy metals showed that Cd was mainly distributed in the south, southwest, southeast and northwest parts of the tailings pond. Pb is mainly distributed in the southeast, the stream under the dam, and the south. Cu was mainly distributed in the south, southwest and the stream direction under the dam. Zn is mainly distributed in the west, southwest, northwest and north. In the semi-variance model parameters, Cd and Zn were dominated by random errors, and the spatial correlation of each point was weak, while Pb and Cu were dominated by structural errors, and the spatial correlation was strong. The spatial variability and correlation of heavy metal content in plants were Zn

The preparation of adsorbent by modified walnut shell using disodium ethylenediamine tetraacetate acid (EDTA-2Na) was studied. The adsorbents were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The results show that under the conditions of Cr(VI) mass concentration of simulated wastewater of 20 mg/L, pH of 2. 0, adsorption time of 260 min, and the dosage of adsorbent of 25 g/L, the adsorption rate of Cr(VI) can reach 99. 59%. The adsorption process is more consistent with Langmuir adsorption isotherm and second-order kinetic equation, and the adsorption process is monolayer adsorption. The characterization results show that the modified walnut shell has developed pore structure and increased specific surface area, and EDTA-2Na is successfully loaded on the surface of walnut shell and shows good adsorption performance for Cr(VI). [ABSTRACT FROM AUTHOR]

The synergistic remediation of plant and microorganism on arsenic/contaminated soil was researched. Thirteen species of plants with good growth and their rhizospheric soil from a tailing area in Hechi,Guangxi were selected as test samples. The arsenic mass fraction is as high as 5. 708 g/kg. The plants which meet the hyperaccumulator conditions are Cyperus alternifolius and Eremochloa ciliaris(Linn. ) Merr. The Cyperus alternifolius has best accmulation and migration effect for arsenic. The strains of CP3 and CP7 are selected from the soil samples with the highest arsenic mass fraction. The results show that the plants' height and fresh weight of mixed bacterium of CP3 and CP7 groups are 57.80% and 46. 51% which are higher than the control group, and the rate of accmulation and migration for arsenic are 64. 87% and 21. 08% which are higher than the control group. It is proved that the mixed bacteria is contribute to Cyperus alternifolius for accumulating arsenic and can be used for synergistic remediation of the arsenic-contaminated soil. [ABSTRACT FROM AUTHOR]

Cervical cancer is the fourth most common cancer among women. Human papilloma virus (HPV) is the most common cause of cervical cancer which accounts for 5% of all human cancers and results in about 528000 cases and 266000 deaths every year. HPV vaccines are considered the most effective strategy for the prevention of HPV infection and cervical carcinoma. Since 2006, three prophylactic vaccines against HPV have been available on the market, including bivalent vaccines, quadrivalent vaccines, and nine-valent vaccines. Among them, nine-valent vaccines have been reported to be the most effective. They can prevent 97% of the high-grade pre-cancer lesions. Virus-like particles (VLPs), which are arranged as 360 copies of capsid proteins L1, are the only antigens of the HPV vaccine. Nine-valent HPV vaccines are prepared by mixing nine types of VLPs with adjuvants. Thus, the quality of the VLPs, including their stability and content in the HPV bulk, is very important for developing HPV vaccines. In this study, a method was developed for the determination of the nine types of VLPs (HPV6/11/16/18/31/33/45/52/58) in HPV bulk by size exclusion chromatography (SEC). The parameters of this method were optimized in terms of column brand, pore size of stationary phase particles, buffer concentration, and pH value. SHIMSEN Ankylo SEC-300 column (300 mm×7.8 mm, 3 μm) combined with a buffer aqueous solution containing 300 mmol/L NaCl and 50 mmol/L phosphate (pH 7.0) was utilized to separate the VLPs from the matrix since a narrow peak shape and good repeatability for VLPs could be obtained with this column and mobile phase. The optimized method had a wide linear range, good repeatability (RSDs of peak area were not more than 5.0%), and a satisfactory sensitivity (LOQs in the range of 4.58-15.24 μg/mL). The optimized method was used to determine the VLPs in the HPV bulk. The LOQs of the current method were much lower than the content of the nine types of VLPs in the HPV bulk, indicating that this method was sensitive enough for the determination of the nine types of VLPs in the HPV bulk. The method was also used to determine the VLPs in an HPV bulk that had been stored at 4 ℃ for one week. A decrease in the nine types of VLPs in the range of 10.0%-62.6% was observed after they were stored at 4 ℃ for one week. An HPV vaccine was prepared by mixing the VLPs with an adjuvant. Thereafter, the VLPs were adsorbed on the surface of the adjuvant. The developed method was applied to determine the free VLPs in twelve batches of HPV vaccines from three different manufacturers. No obvious free protein was detected in the twelve batches of the HPV vaccines from the three manufacturers, indicating that VLPs from these manufactures react well with their aluminum adjuvant. Folin-phenol (Lowry assay) is commonly used for the determination of proteins in vaccines. It is based on the reduction of phosphomolybdotungstic mixed acid chromogen in the phosphomolybdotungstic reagent, which results in an absorbance maximum at 650 nm. The Lowry method was sensitive to interfering substances. Most interfering substances caused a lower color yield, while some detergents caused a slight increase in color. To reduce the effect of the interfering substances, a procedure for precipitating the proteins was usually required before the sample was tested. Thus, the Lowry assay is complex, time-consuming, and of low selectivity. Compared to the Lowry method, the method we developed is simpler and more automatic. It is a high-throughput method of determining VLPs. It can be used to determine VLPs in HPV bulk and free VLPs in HPV vaccines.

The study of protein glycosylation is important to deepening the current understanding of its biological functions as well as to elucidate novel biomarkers of glycosylation. However, glycopeptides must be enriched prior to analysis due to their naturally low abundance. In this study, tryptophan functionalized polymer materials (denoted as Poly-Trp) were synthesized to serve as a novel biomimetic polymers. The resulting materials were characterized by various methods including scanning electron microscopy, thermal analysis, and infrared spectrometry, validating the successful synthesis of Poly-Trp. The retention of glycopeptides on Poly-Trp was investigated revealing that the retention ability decreased as the acetonitrile content of the mobile phase decreased and its acidity increased. Poly-Trp exhibited higher enrichment selectivity for glycopeptides from bovine fetuin than the commercial material ZIC-HILIC, and aminated silica which could defect the interference of 100-fold amount of substance ratios of bovine serum albumin. Poly-Trp is expected to have further applications in the purification of biological samples for the study of glycosylation.

Objective: To analyze the clinical and genetic features of 9 ethnic Han Chinese patients with disseminated superfacial actinic porokeratosis (DSAP)., Methods: Genomic DNA was extracted from peripheral blood samples collected from the patients. PCR and direct sequencing were carried out for five patients from a family, 4 sporadic cases, and 120 healthy controls to identify potential mutations of four genes (MVK, MVD, PMVK, FDPS) involved in the mevalonate pathway as well as SLC17A9, SSH1, and SART3 genes. Pathogenecity of suspected mutations were assessed with SIFT, and Polyphen-2 scores., Results: A c.746T>C mutation was identified in the family and two sporadic cases, while a c.875A>G mutation was identified in another sporadic case. No mutation was identified in the remainder genes among all patients. Scoring has suggested that the c.746T>C and c.875A>G mutations of the MVD gene are probably pathogenic., Conclusion: c.746 T>C and c.875A>G of the MVD gene are most common mutations. Skin rashes of the patients have a strong connection with the sunlight, albeit a significant difference among patients was discovered.

To summarize the nursing experience of 20 cases of high myopia complicated with fixed esotropia. Before surgery, psychological nursing and self-care education were necessary. After the operation, ocular symptoms and complications should be closely observed and treatment in a timely manner. Explicit instructions after discharge and telephone follow-up played a pivotal role in improving clinical efficacy, preventing complications and enhancing patients' quality of life.

Because of the strong polarity of carbohydrate compounds which have weak retention in reverse-phase liquid chromatography (RPLC) , hydrophilic interaction liquid chromatography (HILIC) is suitable for the separation and analysis of the carbohydrate compounds. In this study, nine carbohydrate compounds were selected as the test probes to systematically evaluate the retention behavior of the carbohydrate compounds on a Click TE-Cys column with zwitterionic stationary phase. And the effects of the ratio of organic phase and salt concentration in mobile phase on the retention behavior were investigated as well. The experiments proved that the nine carbohydrate compounds could be eluted in the order of their polarities from the Click TE-Cys column. With the increase of organic phase ratio, the retention of carbohydrate compounds was enhanced. As the increase of salt concentration, the retention of the carbohydrate compounds increased except sialic acid. Using displacement-adsorption liquid phase interaction model to simulate the retention behavior of the carbohydrate compounds under HILIC, the retention behavior of HILIC was described by the retention equation of ln k = a + bln C(B) + cC(B), and the retention values of HILIC were analyzed by multiple linear regression. The results demonstrated that the retention behavior of carbohydrate compounds on the Click TE-Cys was in accordance with the retention regularity of HILIC.

The digest of the standard protein alpha-casein was used as the objective to investigate the influence of pH value of mobile phase on phosphopeptide enrichment selectivity by using Click OEG-CD matrix. Disodium phenyl phosphate was primarily selected as the model sample. The results indicated that phosphate group was difficultly to be ionized when the pH value of mobile phase was below its pKa value. The retention of disodium phenyl phosphate on the Click OEG-CD matrix was not based on ion exchange interaction, leading to the weak retention. The influence of pH value (2, 4 and 6) of mobile phase under hydrophilic interaction liquid chromatography (HILIC) mode on phosphopeptide enrichment selectivity was investigated taking the digest of alpha-casein as a sample. Phosphopeptides could not be enriched on the matrix with the pH value of 2; phosphopeptides could be enriched on the matrix and the elution window was narrow with the pH value of 4; phosphopeptides could be enriched on the matrix while the elution window was broad with the pH value of 6. According to the investigation, Click OEG-CD matrix could be better applied in phosphopeptide enrichment.

Protein phosphorylation is an important post-translational modification (PTM), and involves in many cell activities and disease processes. Nowadays, mass spectrometry (MS) is a powerful tool in peptide-based proteomics. But phosphopeptides, especially multiply phosphorylated peptides, are difficult to be detected by MS. One opinion is that the presence of unphosphorylated peptides lead to the ionization suppression of phosphopeptides. But contrary opinion exists. Moreover, the suppression effect caused by different types of phosphopeptides hasn't been studied yet. In this study, a set of synthetic standard phosphopeptides (singly, doubly and triply phosphorylated peptides) with the same amino acid sequence, and the unphosphorylated peptides were injected into mass spectrometer with or without mixing. Through the ratios of signal intensities of the phosphopeptides before and after mixing, we confirmed that the signals of phosphopeptides were suppressed by those of the unphosphorylated peptides. In addition, the signals of the doubly phosphorylated peptides were slightly suppressed by those of the singly phosphorylated peptides with the same amino acid sequence. The signals of the triply phosphorylated peptides were notably suppressed by the singly and doubly phosphorylated peptides with the same amino acid sequence. Therefore, the singly and multiply phosphorylated peptides should be fractionated and enriched before mass spectrometry analysis.