Endoscopic Ruler for varix size measurement: A multicenter pilot study.

Background: We invented Endoscopic Ruler, a new endoscopic device to measure the size of varices in patients with cirrhosis and portal hypertension.

Aim: To assess the feasibility and safety of Endoscopic Ruler, and evaluate the agreement on identifying large oesophageal varices (OV) between Endoscopic Ruler and the endoscopists, as well as the interobserver agreement on diagnosing large OV using Endoscopic Ruler.

Methods: We prospectively and consecutively enrolled patients with cirrhosis from 11 hospitals, all of whom got esophagogastroduodenoscopy (EGD) with Endoscopic Ruler.

[Different Responses of Soil Microbial Community Structure to Irrigation with Treated Wastewater from Domestic and Industrial Sources].

To investigate the long-term effects of irrigation with treated domestic and industrial wastewater on the microbial community structure of the soil, Illumina MiSeq high-throughput sequencing technology was applied. Groundwater irrigated soil was used as a control. The effects of soil environmental factors and their interactions on the microbial community structure were investigated.

Risk-based prioritization method for the classification of groundwater pesticide pollution from agricultural regions.

Agricultural regions are a significant source of groundwater pesticide pollution. To ensure that agricultural regions with a significantly high risk of groundwater pesticide contamination are properly managed, a risk-based ranking method related to groundwater pesticide contamination is needed. In the present paper, a risk-based prioritization method for the classification of groundwater pesticide pollution from agricultural regions was established.

Degradation of toluene-2,4-diamine by persulphate: kinetics, intermediates and degradation pathway.

In this study, the degradation of toluene-2,4-diamine (TDA) by persulphate (PS) in an aqueous solution at near-neutral pH was examined. The result showed that the degradation rate of TDA increased with increasing PS concentrations. The optimal dosage of PS in the reaction system was determined by efficiency indicator (I) coupling in the consumption of PS and decay half-life of TDA.

[Simulation of nitrate pollution in groundwater using pump-and treat optimization method].

To study the groundwater polluted by nitrate in a landfill site in Beijing, with the pump-and-treat technology, genetic algorithms (GA) and simulated annealing (SA) were used to optimize the cases of 18 planned pumping wells in the groundwater nitrate plume. The optimization method was run to determine the minimum total costs, as a result of the optimal number of wells with the optimal locations and pumping rates. The results of optimization showed that, both GA and SA optimization conditions could reach the desired results, which means that the concentration of nitrate could be reduced to 10 mg x L(-1) after 100 days pumping.

[The remove characteristics of dissolved organic matter in landfill leachate during the treatment process].

In order to investigate remove characteristics of dissolved organic matter in landfill leachate, leachates were sampled during the process (i. e. , adjusting tank, anaerobic zone, oxidation ditch and MBR processing).

Elemental and spectroscopic methods with chemometric analysis for characterizing composition and transformation of dissolved organic matter during chicken manure composting.

Dissolved organic matter was extracted from chicken manure after 1, 8, 16, 28 and 40 days of composting and characterized by combining elemental and spectroscopic methods with chemometric analysis to investigate the evolution of composting materials. The elemental and spectroscopic analysis results showed that the composting process was characterized by the biodegradation of aliphatics, polysaccharide and proteins, as well as by the synthesis of aromatic structures, humic-like substances and macromolecules. Principal component analysis and correlation analysis indicated that the data from elemental and spectroscopic analysis fell into three main groups, and corresponded to the biodegradation, aromatization, and humification and polymerization state of the composting materials.

The independent prokaryotic origins of eukaryotic fructose-1, 6-bisphosphatase and sedoheptulose-1, 7-bisphosphatase and the implications of their origins for the evolution of eukaryotic Calvin cycle.

Background: In the Calvin cycle of eubacteria, the dephosphorylations of both fructose-1, 6-bisphosphate (FBP) and sedoheptulose-1, 7-bisphosphate (SBP) are catalyzed by the same bifunctional enzyme: fructose-1, 6-bisphosphatase/sedoheptulose-1, 7-bisphosphatase (F/SBPase), while in that of eukaryotic chloroplasts by two distinct enzymes: chloroplastic fructose-1, 6-bisphosphatase (FBPase) and sedoheptulose-1, 7-bisphosphatase (SBPase), respectively. It was proposed that these two eukaryotic enzymes arose from the divergence of a common ancestral eubacterial bifunctional F/SBPase of mitochondrial origin. However, no specific affinity between SBPase and eubacterial FBPase or F/SBPase can be observed in the previous phylogenetic analyses, and it is hard to explain why SBPase and/or F/SBPase are/is absent from most extant nonphotosynthetic eukaryotes according to this scenario.

The composition and mercury complexation characteristics of dissolved organic matter in landfill leachates with different ages.

Dissolved organic matter obtained from landfill leachate was separated into hydrophobic acid, base, neutral (HOA, HOB, HON) and hydrophilic (HIM) fractions. Fluorescence excitation-emission matrix spectra and parallel factor analysis were employed to characterize the composition, and fluorescence quenching titration technique was applied to study the complexation between Hg (II) and HON, HOA, and HIM fractions. Protein-like substances, humic-like compounds and xenobiotic organic matters (XOM) were identified in all fractions.

[Research based on 3MRA model about the risk assessment methods and applications of the landfill waste].

Seven major contaminations of the landfill were selected from northeast of China, and the migration and transformation of contaminations environmental medias were studied by using the multimedia multipathway and multireceptor risk assessment (3MRA) model. The results show, the order of the radical concentration of the seven contaminations is Ni2+ > Benzene > Cd > Pb > Cr6+ > As > Hg. The radical concentration of benzene, As and Hg in human is similar to that of ecology, respectively.

Effect of inoculation methods on the composting efficiency of municipal solid wastes.

Four types of inoculation methods were studied during the composting of municipal solid wastes and dry grass (MSWG). The methods included a control group as well as initial-stage, two-stage, and multi-stage inoculations. Fulvic acids were extracted from the composting materials and characterized by spectroscopic techniques.

[Simulation on contamination forecast and control of groundwater in a certain hazardous waste landfill].

On the basis of site investigation and data collection of a certain hazardous waste landfill, the groundwater flow and solute transport coupled models were established by applying Visual Modflow software, which was used to conduct a numerical simulation that forecast the transport process of Cr6+ in groundwater and the effects of three control measures (ground-harden, leakage-proof barriers and drainage ditches) of contaminants transport after leachate leakage happened in impermeable layer of the landfill. The results show that the contamination plume of Cr6+ transports with groundwater flow direction, the contamination rang would reach the pool's boundary in 10 years, and the distance of contamination transport is 1 450 m. But the diffusion range of contamination plume would not be obviously expanded between 10 and 20 years.

[Degradation effect and mechanism of 2,4-DNT by reduction-ZPF catalytic oxidation].

ZPF(zeoliteartificial pillared by alpha-FeOOH) which prepared in the laboratory and characterized by FTIR and XRD was used as catalyst, and was tested for its activity in catalytic H2O2, of 2,4-DNT, which is persistent and difficult to be degraded in groundwater. The degradation of 2,4-DNT was examined at different pHs in the reduction, catalytic oxidation and combination technology of reduction-catalytic oxidation reaction systems. Moreover, the removal effect of 2,4-DNT was compared by these three approaches and the catalytic oxidation mechanism was analyzed.

Fluorescence excitation-emission matrix spectroscopy with regional integration analysis for characterizing composition and transformation of dissolved organic matter in landfill leachates.

Dissolved organic matter (DOM) obtained from landfill leachates was separated into hydrophobic base, hydrophilic matter (HIM), hydrophobic acid (HOA), and hydrophobic neutral fractions. The composition and transformation of the DOM and its fractions were investigated. The results show that the DOM isolated from young, intermediate, and old landfill leachates were mainly composed of tyrosine-, tryptophan-, and humic- and fulvic-like substances, respectively.

[Study on the characteristic UV absorption parameters of dissolved organic matter extracted from chicken manure during composting].

The characteristic parameters obtained from UV-Visible spectra of dissolved organic matter (DOM) during composting were studied in the present paper. The results showed that, during composting progress, the non-humic substances were translated into humus substances, and the aromatization, humification degree and molecular weight of the humus substances increased, while the fatty chains linked with the benzene ring structure were cleavaged into carbonyl, carboxyl and other functional groups. The correlation analysis showed that, when DOM concentration (DOC) from all samples was the same, the specific ultraviolet absorbance values at 254 and 280 nm (SUVA254 and SUVA280, respectively), and the area of a spectrum obtained from 226 to 400 nm (A(226-400)) showed significant positive correlation, furthermore, they were all significantly negatively correlated with the concentration of DOM (DOC), but the correlation between A(226-400) and DOC was the best; The ratio between the absorbance value at 253 nm and that at 203 nm (E253/E203) was significantly correlative with SUVA254, SUVA280 and A 226-400, though the correlation between E253/E203 and DOC was not as good as the other three characteristic parameters; The ratio between the absorbance value at 250 nm and that at 365 nm (E250/E365) and the ratio between the absorbance value at 465 nm and that at 665 nm(E250/E365) were not correlated with the other parameters.

Physicochemical and spectroscopic characteristics of dissolved organic matter extracted from municipal solid waste (MSW) and their influence on the landfill biological stability.

For the purpose of evaluating the stability of municipal solid waste (MSW) excavated from a landfill, dissolved organic matter was extracted and characterized by physicochemical and spectroscopic methods. Results showed that dissolved organic carbon concentration, ratio of dissolved organic carbon to dissolved organic nitrogen, and specific ultraviolet absorbance at 254 nm were in the range of 0.383-3.

[Effect of pH on the fluorescence characteristic of dissolved organic matter in landfill leachate].

Due to its high sensitivity, good selectivity and nondestructivity nature, fluorescence technique is suitable to the study of DOM. In the present study, fluorescence characteristics of dissolved organic matter (DOM) from three different ages of landfill leachate (1a, 5a, 10a) under different pH value were investigated. The fluorescence synchronous scan spectroscopy showed that, in addition to the characteristic each age of landfill leachate owned separately, DOM from three ages of landfill leachate shared some common characteristics with the change in pH as follows: the fluorescence peaks of DOM exhibited in synchronous scan spectroscopy from 1 and 5-year-old leachate showed the maximum fluorescence intensity at pH 5, while that of DOM from 10-year-old landfill leachate appeared at pH 12, and the fluorescence intensity of most fluorescence peaks of DOM from 10-year-old landfill leachate exhibited in synchronous scan spectroscopy at pH 4 ranked second.

[Spectroscopic characterization indicator of landfill in the process of stabilizing].

In the present study, dissolved organic matter (DOM) extracted from landfill of four different ages was studied with fluorescence and ultraviolet-visible spectroscopy in order to explore the possibility of using spectral characteristic changes of DOM as stabilization indicators for landfill. The three-dimensional fluorescence excitation-emission matrix spectroscopy (EEM) displayed that DOM of 0-year-old contained mainly protein-like matter, while DOM extracted from 1, 5 and 10-year-old consisted chiefly of humic matter-like substance, and the intensity change of DOM of 1, 5 and 10-year-old landfill was disordered. Besides, the fluorescence spectroscopy also showed that the r(A,C) value and the fluorescence index f(450/500) of DOM of four different years both decreased with landfill age, which indicated that the low molecular weight fraction of DOM was translated into the high molecular aromatic matter and the degree of humification was enhanced with the time increasing.

[Fluorescence spectroscopic chracterization of the complexation between mercury(II) and dissolved organic matter].

In this study, conventional fluorescence spectroscopy in the excitation, emission and synchronous scan modes and three-dimensional fluorescence spectroscopy in the form of excitation-emission matrix of fluorescence intensity as a function of excitation and emission wavelengths were applied to study the complexation between DOM extracted from landfill leachates and Hg(II) ions. The emission spectrum of DOM exhibited a broad peak with a center at 425 nm and a disorder change of the peak with increasing Hg(II) concentrations, which suggested that the structure of DOM was comparatively simple and the fluorescence character of DOM-Hg(II) complexes resulted from interaction of all fluorescence groups. The excitation spectrum of DOM showed that the intensities of two peaks at 392 and 458 nm both decreased with the addition of Hg(II), indicating that different sources, hydroxy and amido groups, were all involved in the DOM-Hg(II) complexation process.

[Study on fluorescence characteristic of dissolved organic matter from municipal solid waste landfill leachate].

In the present study, the samples of leachate of 0, 5, 10-years-old landfill were respectively taken from landfill plant, the dissolved organic matter (DOM) was extracted from landfill leachate, and the fluorescence spectra of DOM were determined. The fluorescence synchronous scan spectra of DOM in 0-year-old leachate exhibited a primary peak at 335 nm, a secondary peak at 455 nm, and a shoulder peak at 385 nm. While the fluorescence intensities of DOM at different peaks were decreased for 5-year-old leachate, especially those of the peaks at shorter wavelengths (335 and 385 nm) which may be ascribed that the simpler structural components were decreased sharply.

[Study on three-dimensional fluorescence spectroscopy characteristics of humic acid during composting with microbes inoculation].

Composting is one of the municipal solid wastes (MSW) treatment ways. In order to increase composting humification process, in the present study, inoculation microbes were used in MSW composting. The experiment design included RUNck with no microbes inoculation and RUNmic with microbes inoculation.

[Phosphate transform of composting with pre-mixing insoluble phosphate using high temperature dissolved phosphorus microbes inoculation].

In order to enhance the available phosphorus (P) of compost production, the experimental design of composting included three treatments was conducted. The treatments were: Control (CK) with no dissolved phosphate microbes inoculation, no rock phosphate mixing; CP with no dissolved phosphate microbes inoculation, rock phosphate mixing; CMP with dissolved phosphate microbes inoculation, rock phosphate mixing. At different composting phases, the samples were taken for the determination of phosphorus forms.

[Effect of using three stages inoculation controlled by temperature on organic matter transformation during composting process].

In order to accelerate composting efficiency, municipal solid wastes (MSW) composting was conducted using three stages inoculation controlled by temperature (TSCT). At different composting phases, the samples were taken for the determination of organic matter transformation. Compared to routine inoculation method (CK), total organic carbon (TOC), dissolved organic matter (DOM) of TSCT decrease by 6.

[Effect of different extractants on leaching characteristics of the fly ash from municipal solid waste incinerator].

The effect of three extractants, which are HNO3/NaOH, CH3COOH/NaOH, and HNO3-H2SO4 , on leaching characteristics of the fly ash from municipal solid waste incinerator (MSWI) was investigated. The results showed that: (1) different extractants had different buffering capacities for the leaching solutions of the fly ash from MSWI, which are in the order of HAC > HNO3-H2SO4 > HNO3. (2) HAC showed better dissolvability to Zn, Cd, and Cr than HNO3-H2SO4, under more acidic condition, but the leaching concentration of Pb was not affected by extractant types obviously.