[The ability of gap detection in patients with acoustic neuroma].

Objective:We aimed to provide a basis for the clinical study of acoustic neuroma through investigating the ability of temporal gap detection in acoustic neuroma patients and comparing the abilities with those in people with normal and impaired hearing. Method:Twenty-two patients with confirmed acoustic neuroma, 30 normal hearing patients and 16 patients with sensorineural hearing loss were enrolled in this study, and the interval threshold for awareness of each group was tested. Result:The mean temporal gap detection test（TGDT） threshold of the normal hearing group was （3.56±0.82） ms; the sensorineural hearing loss group's was （3.91±1.46） ms; TGDT threshold of healthy side of acoustic neuroma patients was （4.01±1.86） ms; TGDT threshold of the impaired side of acoustic neuroma patients was （9.48±9.46）ms. After statistical analysis, we found that excepting for the test of phonetically balanced maximum （PBmax） and TGDT, other results in the sensorineural hearing loss group and normal hearing group is of no statistical difference. The difference between the affected side of the acoustic neuroma group and the other groups was statistically significant （P<0.05）. There was no linear correlation between the value of TGDT threshold and PBmax （P> 0.05）. TGDT value of normal people has no significant difference among people of different genders and ears of different individuals. Conclusion:The TGDT of the healthy ear of the patients with acoustic neuroma is not affected, and there is no significant change compared with normal people. The TGDT test has a good consistency with the PBmax results. The time interval response ability of the affected ear of the acoustic neuroma is significantly weaker than that of the normal person. The combined test of PBmax and TGDT will contribute to the diagnosis of retrocochlear disease.

Low-to-High Confinement Transition Mediated by Turbulence Radial Wave Number Spectral Shift in a Fusion Plasma.

A new model for the low-to-high (L-H) confinement transition has been developed based on a new paradigm for turbulence suppression by velocity shear [G. M. Staebler et al., Phys. Rev. Lett. 110, 055003 (2013)]. The model indicates that the L-H transition can be mediated by a shift in the radial wave number spectrum of turbulence, as evidenced here, for the first time, by the direct observation of a turbulence radial wave number spectral shift and turbulence structure tilting prior to the L-H transition at tokamak edge by direct probing. This new mechanism does not require a pretransition overshoot in the turbulent Reynolds stress, shunting turbulence energy to zonal flows for turbulence suppression as demonstrated in the experiment.

New edge coherent mode providing continuous transport in long-pulse H-mode plasmas.

An electrostatic coherent mode near the electron diamagnetic frequency (20-90 kHz) is observed in the steep-gradient pedestal region of long pulse H-mode plasmas in the Experimental Advanced Superconducting Tokamak, using a newly developed dual gas-puff-imaging system and diamond-coated reciprocating probes. The mode propagates in the electron diamagnetic direction in the plasma frame with poloidal wavelength of ∼8 cm. The mode drives a significant outflow of particles and heat as measured directly with the probes, thus greatly facilitating long pulse H-mode sustainment. This mode shows the nature of dissipative trapped electron mode, as evidenced by gyrokinetic turbulence simulations.

The combined effect of bacteria and Chlorella vulgaris on the treatment of municipal wastewaters.

Impacts of Chlorella vulgaris with or without co-existing bacteria on the removal of nitrogen, phosphorus and organic matter from wastewaters were studied by comparing the wastewater treatment effects between an algae-bacteria consortium and a stand-alone algae system. In the algae-bacteria system, C.vulgaris played a dominant role in the removal of nitrogen and phosphorus, while bacteria removed most of the organic matter from the wastewater. When treating unsterilized wastewater, bacteria were found to inhibit the growth of algae at >231 mg/L dissolved organic carbon (DOC). Using the algae-bacteria consortium resulted in the removal of 97% NH4(+), 98% phosphorus and 26% DOC at a total nitrogen (TN) level of 29-174 mg/L. The reaction rate constant (k) values in sterilized and unsterilized wastewaters were 2.17 and 1.92 mg NH4(+)-N/(mg algal cell ·d), respectively.

Endoscopic mucosal resection vs endoscopic submucosal dissection for rectal carcinoid tumours: a systematic review and meta-analysis.

AIM: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are used for the removal of rectal carcinoid tumours. There are no current guidelines or consensus on the optimal treatment strategy for these lesions. A systematic review was conducted to compare the efficacy and safety of ESD and EMR. METHOD: The generation of inclusion criteria and analysis of data were based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations. A systematic literature review was conducted using the following databases: Medline, Embase, SpringerLink, Elsevier ScienceDirect, Science Citation Index and the Cochrane Library. Only papers comparing treatment of rectal carcinoid tumours by EMR and by ESD were selected. The data collected included the patients' demographic information, interventions made, observed outcome and sources of bias. RESULTS: Four papers were included in this systematic review and meta-analysis. ESD was more effective than EMR in complete resection (OR 0.29; 95% CI 0.14-0.58; P = 0.000). ESD was as safe as EMR [rate difference (RD) -0.01; 95% CI -0.07 to 0.05; P = 0.675]. Recurrence rates did not differ significantly between the EMR and ESD groups (RD 0.04; 95% CI -0.01 to 0.09; P = 0.150). The duration of ESD was longer than EMR (standardized mean difference -1.73; 95% CI -2.73 to -0.74; P = 0.001). CONCLUSION: The study indicates that ESD is the better treatment for rectal carcinoid tumours.

Cultivation of Chlorella vulgaris on wastewater containing high levels of ammonia for biodiesel production.

The feasibility of cultivating Chlorella vulgaris with wastewater containing high ammonia nitrogen concentrations was examined. The average specific growth rate of C. vulgaris was 0.92 d(-1) at 17 mg L(-1) NH4+-N, but declined to 0.33 d(-1) at NH4+-N concentrations of 39-143 mg L(-1). At 39 mg L(-1) NH4+-N, lipid productivity reached a maximum value (23.3 mg L(-1)d(-1)) and dropped sharply at higher NH4+-N levels, which demonstrated NH4+-N should be controlled for biodiesel production. C16 and C18 fatty acids accounted for 80% of total fatty acids. Increasing NH4+-N from 17 to 207 mg L(-1) yielded additional short-chain and saturated fatty acids. Protein content was in positive correlation with NH4+-N content from 17 mg L(-1) (12%) to 207 mg L(-1) (42%). Carbohydrate in the dried algae cell was in the range of 14-45%, with a peak value occurring at 143 mg L(-1) NH4+-N. The results demonstrate that product quality can be manipulated by NH4+-N concentrations of the initial feeds.

Comparison of different fluorescence spectrum analysis techniques to characterize humification levels of waste-derived dissolved organic matter.

In the present work, the humification level of waste-derived dissolved organic matter (DOM) at different waste biostability was investigated, by using fluorescent excitation-emission matrix (EEM) scanning. Different fluorescence spectrum analysis techniques were applied and compared. Experimental results demonstrate that parallel factor (PARAFAC) analysis was sensitive to reflect DOM humification, and the most reasonable to deconstruct DOM compositions, when compared with other spectrum analysis techniques. It suggests applying the DOM-EEM-PARAFAC pipeline for rapid estimation of waste biostability.

New dual gas puff imaging system with up-down symmetry on experimental advanced superconducting tokamak.

Gas puff imaging (GPI) offers a direct and effective diagnostic to measure the edge turbulence structure and velocity in the edge plasma, which closely relates to edge transport and instability in tokamaks. A dual GPI diagnostic system has been installed on the low field side on experimental advanced superconducting tokamak (EAST). The two views are up-down symmetric about the midplane and separated by a toroidal angle of 66.6°. A linear manifold with 16 holes apart by 10 mm is used to form helium gas cloud at the 130×130 mm (radial versus poloidal) objective plane. A fast camera is used to capture the light emission from the image plane with a speed up to 390,804 frames/s with 64×64 pixels and an exposure time of 2.156 µs. The spatial resolution of the system is 2 mm at the objective plane. A total amount of 200 Pa.L helium gas is puffed into the plasma edge for each GPI viewing region for about 250 ms. The new GPI diagnostic has been applied on EAST for the first time during the recent experimental campaign under various plasma conditions, including ohmic, L-mode, and type-I, and type-III ELMy H-modes. Some of these initial experimental results are also presented.

Meta-analysis: the efficacy and safety of certolizumab pegol in Crohn's disease.

BACKGROUND: Certolizumab pegol is the third anti-TNF-alpha agent approved by the Food and Drug Administration of the United States. AIM: To provide a comprehensive up-to-date review of the efficacy and safety of certolizumab in Crohn's disease (CD). METHODS: Electronic databases, including PubMed, EMBASE, the Cochrane library and the Science Citation Index, were searched to retrieve relevant trials. In addition, meeting abstracts and the reference lists of retrieved articles were reviewed for further relevant studies. RESULTS: Three trials, enrolling a total of 1040 patients, are included in the meta-analysis to evaluate the short-term efficacy of certolizumab, which is effective for rapid induction and long-term maintenance of clinical response or remission and can improve quality of life in patients with Crohn's disease. Certolizumab is also effective for patients who have lost response to infliximab. However, its efficacy in infliximab-exposed patients is probably less than in infliximab-naive patients. Re-induction with certolizumab in patients who have flared on maintenance therapy can rescue a significant proportion of patients. There is no significant association between the efficacy of certolizumab and the baseline C-reactive protein level. In comparison with placebo, certolizumab does not increase the risk of serious adverse events. CONCLUSIONS: Certolizumab is effective and safe in treating Crohn's disease. Further studies are still required to assess its full safety profile.

Synergetic effect of pH and biochemical components on bacterial diversity during mesophilic anaerobic fermentation of biomass-origin waste.

AIMS: To investigate the synergetic effect of pH and biochemical components on bacterial community structure during mesophilic anaerobic degradation of solid wastes with different origins, and under acidic or neutral conditions. METHODS AND RESULTS: The bacterial community in 16 samples of solid wastes with different biochemical compositions and origins was evaluated during mesophilic anaerobic degradation at acidic and neutral pH. Denaturing gradient gel electrophoresis (DGGE) and single-strand conformation polymorphism (SSCP) were used to compare the communities. Multivariate analysis of the DGGE and SSCP results revealed that most of the dominant microbes were dependent on the content of easily degradable carbohydrates in the samples. Furthermore, the dominant microbes were divided into two types, those that preferred an acid environment and those that preferred a neutral environment. A shift in pH was found to change their preference for medium substrates. Although most of the substrates with similar origin and biochemical composition had similar microbial diversity during fermentation, some microbes were found only in substrates with specific origins. For example, two microbes were only found in substrate that contained lignocellulose and animal protein without starch. These microbes were related to micro-organisms that are found in swine manure, as well as in other intestinal or oral niches. In addition, the distribution of fermentation products was less sensitive to the changes in pH and biochemical components than the microbial community. CONCLUSIONS: Bacterial diversity during anaerobic degradation of organic wastes was affected by both pH and biochemical components; however, pH exerted a greater effect. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study reveal that control of pH may be an effective method to produce a stable bacterial community and relatively similar product distribution during anaerobic digestion of waste, regardless of variation in the waste feedstocks.

Impact of recycled effluent on the hydrolysis during anaerobic digestion of vegetable and flower waste.

Two trials were established to investigate the effect of recycled effluent on hydrolysis during anaerobic co-digestion of vegetable and flower waste. Trial I evaluated the effect by regulating the flow rate of recycled effluent, while Trial II regulated the ratio of hydrolytic effluent to methanogenic effluent, which were recycled to hydrolysis reactor. Results showed that the recirculation of methanogenic effluent could enhance the buffer capability and operation stability of hydrolysis reactor. Higher recycled flow rate was favourable for microbial anabolism and further promoted hydrolysis. After 9 days of hydrolysis, the cumulative SCOD in the hydrolytic effluent reached 334, 407, 413, 581 mg/g at recycled flow rates of 0.1, 0.5, 1.0, 2.0 m3/(m3 x d), respectively. It was feasible to recycling a mixture of hydrolytic and methanogenic effluent to the hydrolysis reactor. This research showed that partially introducing hydrolytic effluent into the recycled liquid could enhance hydrolysis, while excessive recirculation of hydrolytic effluent will inhibit the hydrolysis. The flow ratio 1:3 of hydrolytic to methanogenic effluent was found to provide the highest hydrolysis efficiency and degradation rate of lignocelluloses-type biomass, among four ratios of 0:1, 1:3, 1:1 and 3:1. Under this regime, after 9 days of hydrolysis, the cumulative TOC and TN in the hydrolytic effluent reached 162 mg/g and 15 mg/g, the removal efficiency of TS, VS, C and cellulose in the solid phase were 60.66%, 62.88%, 58.35% and 49.12%, respectively. The flow ratio affected fermentation pathways, i.e. lower ratio favoured propionic acid fermentation and the generation of lactic acid while higher ratio promoted butyric acid fermentation.

Partition of six phthalic acid esters in soluble and solid residual fractions of wastewater sludges.

Distributions of six priority controlled Phthalic acid esters (PAEs), including di-methyl phthalate (DMP), di-ethyl phthalate (DEP), di-butyl phthalate (DBP), benzyl butyl phthalate (BBP), di-(2-ethylhexyl) phthalate (DEHP), di-octyl phthalate (DOP) were studied based on soluble and insoluble fractions of sludge samples collected at four wastewater treatment plants in Shanghai, China. Three sludge samples comprised hydrophilic colloidal particles of high protein contents and low aromaticity. Meanwhile, these sludges contained DBP of 4.2 to approximately 5.7 mg kg(-1) dried solids (ds) and DEHP of 21.1 to approximately 55.6 mg kg(-1) ds, respectively. Another sludge sample comprised mainly hydrophobic colloidal particles of humic substances and high aromaticity. It contained DBP of 1.18 mg kg(-1) ds and DEHP of 2.89 mg kg(-1) ds, respectively. The most abundant components noted amongst the six studied PAEs were DBP and DEHP, which mostly associated with the insoluble fraction of sludge. Specifically, the DBP and DEHP in insoluble fraction (the solid residual phase) accounted for 89.8 to approximately 98.2% and 88.6 to approximately 99.6% of those in the whole sludge. The partition coefficients of DBP and DEHP for the soluble and insoluble fractions of sludge correlated with the suspension SUVA254, suggesting that interaction between pi-electrons of DBP or DEHP and those of organic particulates in suspension contributes most of the sorption processes.

Role of dissolved humic substances surrogates on phthalate esters migration from sewage sludge.

The facilitated transport of dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP), the priority endocrine disrupting chemicals in sludge, by dissolved humic substances (HS) was evaluated by batch extraction. The DBP, much less hydrophobic than DEHP, was inclined to migrate from sludge matrix into humic substances solutions, while the DEHP could not migrate facilitated by most humic and fulvic acids solutions, except the humic acid surrogate of high humification. This result revealed that the affinity of DEHP in sludge matrix exceeded DBP and was not susceptible by weak HS. The hydrophobic property controlled the association of phthalic acid esters on sludge residual phases. Migration rate of DBP was positively correlated to the weight-average molecular weight of HS surrogates and the aromatic extents of HA. Some functional groups in HS molecules benefited to the facilitated transport of DBP.

Bacterial community dynamics and product distribution during pH-adjusted fermentation of vegetable wastes.

AIMS: To estimate the effect of pH on the structures of bacterial community during fermentation of vegetable wastes and to investigate the relationship between bacterial community dynamics and product distribution. METHODS AND RESULTS: The bacterial communities in five batch tests controlled at different pH values [uncontrolled (about pH 4), 5, 6, 7 and 8] were monitored by denaturing gradient gel electrophoresis (DGGE) and single-strand conformation polymorphism (SSCP). The two fingerprinting methods provided consistent results and principal component analysis indicated a close similarity of bacterial community at pH 7 and 8 in addition to those at pH 4-6. This clustering also corresponded to dominant metabolic pathway. Thus, pH 7-8 shifted from alcohol-forming to acid-forming, especially butyric acid, whereas both alcohol-forming and acid-forming dominated at pH 5-6, and at pH 4, fermentation was inhibited. Shannon-weaver index was calculated to analyse the DGGE profiles, which revealed that the bacterial diversities at pH 7 and 8 were the highest while those at pH 5 and 4 (uncontrolled) were the lowest. According to sequencing results of the bands excised from DGGE gels, lactic acid bacteria and Clostridium sp. were predominant at all pH values, but varieties in species were observed as pH changed and time prolonged. CONCLUSIONS: The bacterial community during fermentation was materially influenced by pH and the diverse product distribution was related to the shift of different bacterial population. SIGNIFICANCE AND IMPACT OF THE STUDY: The study reveals that the impact of pH on fermentation product distribution is implemented primarily by changes of bacterial community. It also provides information about the comparison of two fingerprinting methods, DGGE and SSCP.

Effect of alkali metal cation on the anaerobic hydrolysis and acidogenesis of vegetable waste.

Five batch testing scenarios were designed to evaluate the effects of alkali metal cations on anaerobic hydrolysis and acidogenesis. These scenarios were A (c=0 g l(-1)), B (cNa+=25 g l(-1)), C (cNa+=50 g l(-1)), D (cK+=25 g l(-1)), and E (cK+=50 g l(-1), pH 7.0). A solution pH of 7.0 or above favored protein hydrolysis, higher proteinase activity and higher ammonia production. However, such a pH suppressed carbohydrate hydrolysis, as indicated by low alpha-amylase activity. Cation interference at pH 5.0-6.0 seemed not to affect carbohydrate hydrolysis, as showed by the unimpaired alpha-amylase activity at 50 g l(-1) K+. Acidogenesis was more sensitive to alkali metal cations, so acid production and the drop in pH were lowest in a 25-50 g l(-1) Na+, acidic environment (pH 4.0-6.0). It was insensitive to cations when the pH was maintained at 7.0-8.0. When the pH was uncontrolled and decreased freely to acidic values, 25 g l(-1) of cation inhibited the action of the microbes, which rapidly acclimated, as presented by the slow transformation of soluble polymers to soluble metabolites. However, acidogenetic microbes could not easily recover from inhibition by 50 g l(-1) of cation. When the pH was maintained at over 7.0, the microbes were not inhibited by cation (50 g l(-1)) as indicated by the more active acidogenesis. The metabolic pathways to lactate, acetate and alcohols were not fully coupled.

Nitrogen removal from recycled landfill leachate by ex situ nitrification and in situ denitrification.

A three-compartment system, comprising a landfill column with fresh municipal solid waste, a column with a well-decomposed refuse layer as methane producer, and a sequential batch reactor as ex situ nitrifying reactor, was employed to remove nitrogen from municipal solid waste leachate. Since food waste comprised a major portion of refuse collected in Shanghai, an intense hydrolysis reaction occurred and caused the rapid accumulation of ammonia nitrogen (NH(3)-N) and total organic carbon in the leachate. This paper discusses the role of the three mentioned units and the design and operation of the proposed system. With most NH(3)-N being converted to nitrite nitrogen (NO(2)(-)-N) or nitrate nitrogen (NO(3)(-)-N) by the nitrifying reactor, and with the well-decomposed refuse layer transforming most dissolved organic compounds to CO(2), carbonates and methane, it was found that the fresh refuse column could efficiently denitrify the hydrolyzed nitrogen to N(2) gas. The role of the three mentioned units and comments on the design and operation of the proposed system are also discussed.

Nitrogen removal from landfill leachate using single or combined processes.

The municipal solids waste (MSW) collected at Shanghai includes a high proportion of food waste, which is easily hydrolyzed to generate ammonia-nitrogen in leachate. This study investigated the efficiency of nitrogen removal from landfill leachate employing four different treatment processes. The simulated rainfall and direct leachate recycling produced strong leachate with high ammonia-nitrogen content, and resulted in the removal of only a small amount of nitrogen. Although pretreating the leachate using an aerobic reactor removed some nitrogen, most of which was transformed to biomass because of the high organic loading applied. Using the three-compartment system, which comprises a landfill column with fresh MSW, a column with well-decomposed refuse layer as the methane generator, and a nitrifier, the ammonia-nitrogen was converted into nitrogen gas and hence removed. Experimental results demonstrated the feasibility of adopting the three-compartment system for managing nitrogen in landfill leachate generated from high-nitrogen-content MSW.

Clean-up and disposal process of polluted sediments from urban rivers.

In this paper, the discussion is concentrated on the properties of the polluted sediments and the combination of clean-up and disposal process for the upper layer heavily polluted sediments with good flowability. Based on the systematic analyses of various clean-up processes, a suitable engineering process has been evaluated and recommended. The process has been applied to the river reclamation in Yangpu District of Shanghai City, China. An improved centrifuge is used for dewatering the dredged sludge, which plays an important role in the combination of clean-up and disposal process. The assessment of the engineering process shows its environmental and technical economy feasibility, which is much better than that of traditional dredging-disposal processes.