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For tunnelling in urban areas, the current sequential excavation (SE) method usually increases the number of temporary drifts to achieve better control of surface settlements, which may prolong construction duration. In this case study, a four-drift SE method, termed the suspension-type centre cross diaphragm (S-CRD) method, was proposed and applied to the construction of a large cross-section tunnel in soft ground, where normally the six-drift double-side drift (DSD) method would be adopted. Field monitoring results and statistical data indicated that, in comparison with the six-drift DSD method, the four-drift S-CRD method achieved better control of the surface settlements while improving the efficiency of construction by 30%. The advantages of the S-CRD method, i.e., safe and rapid construction, were eminently clear.

Hyperspectral image (HSI) contains rich spatial and spectral information, which has been widely used in resource exploration, ecological environment monitoring, land cover classification and target...

To explore the differences in the nutritional quality of the muscles of bighead carp from different environments and aquaculture systems, we investigated three types of water bodies typically used for aquaculture: A common culture pond (NC), a natural lake (PY), and a cold water reservoir (XHK). Parameters affecting quality were evaluated, including muscle microstructure, fatty acid profiles, amino acid profiles, and volatile compounds. Fish from the XHK reservoir had the smallest muscle fiber diameter and the highest muscle fiber density (25.3 fibers/0.01 mm2), while muscle fiber density was lowest in fish from the NC pond (9.7 fibers/0.01 mm2). The bighead carp from the XHK reservoir had a much wider variety of unsaturated fatty acids, as well as higher levels of total polyunsaturated fatty acids. Eicosapentaenoic acid (EPA), docosahexenoic acid (DHA), and arachidonic acid (AA) were all significantly more abundant in the XHK group, increases of 7.48%, 12.12%, and 17.49%, respectively (P

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been widely detected in wastewater and surface water, indicating that the removal of NSAIDs by wastewater treatment plants was not efficient. Electrochemical advanced oxidation technology is considered to be an effective process. This study presents an investigation of the kinetics, mechanism, and influencing factors of diclofenac (DCF) degradation by an electrochemical process with boron-doped diamond anodes. Relative operating parameters and water quality parameters are examined. It appears that the degradation follows the pseudo-first-order degradation kinetics. DCF degradation was accelerated with the increase of pH from 6 to 10. The degradation was promoted by the addition of electrolyte concentrations and current density. Humic acid and bicarbonate significantly inhibited the degradation, whereas chloride accelerated it. According to the quenching tests, hydroxyl radicals (•OH) and sulfate radicals contributed 76.5% and 6.5%, respectively, to the degradation. Sodium sulfate remains a more effective electrolyte, compared to sodium nitrate and sodium phosphate, suggesting the quenching effect of nitrate and phosphate on •OH. Major DCF transformation products were identified. According to the degradation products detected by liquid chromatography–mass spectrometry, hydroxylation and decarboxylation are the main pathways of DCF degradation; while dechlorination, chlorination, and nitro substitution are also included in this electrochemical degradation process. Highlights The electrochemical degradation of DCF at BDD anodes follows pseudo-first-order kinetics.; •OH contributes more than SO4•–, but the effect of SO4•– cannot be ignored.; The presence of Cl− significantly accelerated the degradation of DCF.; Hydroxylation and decarboxylation are main pathways in DCF degradation.

The object of this work is to investigate the effects of emodin and curcumin on Pengze crucian carp. Fish was, respectively, fed Control diet and supplementation of 50 mg/kg emodin (EM group) and curcumin (CU group) with 4 repetitions each group (20 fish per cage). Our results indicated that the growth was unaffected by diets, whilst whole‐body lipid content was detected to remarkably decrease in EM group. Two additives exerted positive impacts on antioxidant system through elevation of antioxidant enzymes activities and antioxidants content. The improvement of intestinal antioxidant property appeared to be associated with up‐regulating expression of antioxidant genes through nuclear factor erythroid 2‐related factor 2 (Nrf2) activation. Moreover, intestinal inflammatory response was suppressed in EM and CU groups through inhibition of Toll‐like 4 receptor (TLR4) signalling pathway and pro‐inflammatory cytokine genes expression, and it may be related to the regulation of antioxidant system and overexpression of interleukin‐10. Afterwards, intestinal barrier function was enhanced in EM and CU groups by inducing the expression of tight junction protein genes. These results revealed that emodin and curcumin exerted positive benefits on the health of Pengze crucian carp by enhancing antioxidant capacity, suppressing inflammatory response and improving intestinal barrier function.

Visible-near infrared spectroscopy is considered an effective method for rapidly determining total carbon (TC) and total nitrogen (TN) in terrestrial soils. However, reports on measuring them by VNIR in marine sediments are limited. This article provides an analysis and spectral model comparison of TC and TN in marine sediments using VNIR. The best TC and TN spectral models were established when using the least square support vector machine algorithm with a wavelength, which extended from 226 nm to 975 nm. The prediction results of TN have a high coefficient of determination and residual predictive deviation, providing accurate quantitative predictions. The TC spectral model comes with a disadvantage might due to its usual high concentrations of organic carbon. Characteristic wavelength extraction may lead to the loss of identification information for the characteristics of TC and TN, and full wavelength spectrum contains more information helps more to the quantification.

The real-time and rapid detection of soil carbon and nitrogen content is of great significance to promote ecosystem carbon balance, ensure the healthy growth of crops, sustainable land use, prediction and early warning of soil pollution. Hyperspectral image is a promising alternative to predict soil carbon and nitrogen elements. Considering some noise and interference information in hyperspectral image, a new feature selection algorithm, extend successive projections algorithm (ESPA), was proposed. Compared with the prediction using full spectrum, successive projection algorithm (SPA), uninformative variable elimination (UVE), genetic algorithm (GA) and manual selection of feature spectra, the prediction was improved by using ESPA selecting the spectral region. The result indicates that the selected spectral region using ESPA is effective in prediction of soil total carbon (TC) and total nitrogen (TN) content, providing an alternative to predict carbon and nitrogen content in soil using hyperspectral image.

Visible and near infrared spectroscopy (VNIR) has been successfully used to determine many soil parameters rapidly. However, total phosphorous (P) cannot be well quantified by VNIR, mainly because its absorption spectrum or reflectance spectrum was too weak to be studied. Here, we explored a new way to reveal the reflectance spectrum of total P in soils. Firstly, six types of soil residues were prepared after the original soil was sequentially extracted Ca2-P, Ca8-P, Al-P, Fe-P, O-P, and Ca10-P, respectively. Secondly, the reflectance spectra of these P fractions were obtained using these soil residues by QE65000 spectrometer (Ocean Optics). Specifically, if we intended to get the spectrum of a certain P fraction, we would measure the reflectance spectrum of the soil residues without its neighboring former P fraction, using the soil residues after extracting this P fraction as the reference spectrum. Results showed that these P fractions had different characteristics of reflectance spectrum and can be well analyzed qualitatively and quantitatively. After summarizing the diagnostic spectra of these P fractions, the total P diagnostic spectrum was found to be distributed in 250–750 nm. Using these diagnostic bands, the spectral model of total P was established and showed a better result. This study provided an important evidence for understanding the characteristics of total P reflectance spectrum in soils and predicting total P concentrations.

Changes in land cover will cause the changes in the climate and environmental characteristics, which has an important influence on the social economy and ecosystem. The main form of land cover is different types of soil. Compared with traditional methods, visible and near-infrared spectroscopy technology can classify different types of soil rapidly, effectively, and nondestructively. Based on the visible near-infrared spectroscopy technology, this paper takes the soil of six different land cover types in Qingdao, China orchards, woodlands, tea plantations, farmlands, bare lands, and grasslands as examples and establishes a convolutional neural network classification model. The classification results of different number of training samples are analyzed and compared with the support vector machine algorithm. Under the condition that Kennard–Stone algorithm divides the calibration set, the classification results of six different soil types and single six soil types by convolutional neural network are better than those by the support vector machine. Under the condition of randomly dividing the calibration set according to the proportion of 1/3 and 1/4, the classification results by convolutional neural network are also better. The aim of this study is to analyze the feasibility of land cover classification with small samples by convolutional neural network and, according to the deep learning algorithm, to explore new methods for rapid, nondestructive, and accurate classification of the land cover.

This article focuses on traveling waves including peakons, periodic peakons, compactons and solitary waves as well as the persistence of some of these waves in a generalized Camassa–Holm (gCH) equation involving dual-power law nonlinearities. Firstly, we analyze the global phase portraits of the associated traveling wave system by a dynamical system-based approach. All the traveling waves are classified and their corresponding parameter conditions are obtained. It is found that the gCH equation with dual-power law nonlinearities can admit different peakons under different parameter conditions. Secondly, we pay attention to the persistence of solitary waves, i.e., the existence of solitary waves in a perturbed gCH equation by using geometric singular perturbation theory (GSPT) and an “explicit” Melnikov method. An elementary method to calculate the unperturbed homoclinic orbits and the associated Melnikov integral in an “explicit” way is developed in this article.

The photoelectric properties of LED are affected by driving current and ambient temperature. To solve the problem of light wane caused by excessive current and overheating, LLC resonant converter with soft switching was chosen as the main topology, improving the power efficiency, and reducing the heat of the LED driver. Firstly, the soft-switching conditions of the LLC resonant converter are analyzed, and the constraint equation is obtained. Then, an improved particle swarm optimization algorithm is proposed to optimize the resonant parameters. The weight of particles is dynamically and adaptively changed to balance the global and local optimization performance of particles. Finally, the controller is designed to realize constant current. This design improves the efficiency of the LED driver. At the same time, the light wane is effectively suppressed by stable output current, and the rationality of the selected parameters is verified by simulation and experiment.

Excessive use of plant protein can cause various diseases, and functional additives have been proven to improve the health of aquatic fish but its underlying mechanism is still unclear. A 60-day trial was conducted to explore the action mechanism of β-glucan (1 g/kg), inulin (1 g/kg) and emodin (0.1 g/kg) supplementation improving the health of grass carp (initial weight 27.19 ± 0.05 g) fed low fishmeal diet. Our results indicated that emodin exhibited a positive impact on the growth of grass carp. Diet with β-glucan, inulin and emodin displayed hepatoprotective effects through the suppression of activities of serum alanine aminotransferase, aspartate aminotransferase and γ‐glutamyl transaminase, and β-glucan and inulin exerted hypocholesterolemic effects simultaneously. High level of antioxidant parameters in serum and intestine tissue confirmed the antioxidant property of β-glucan, inulin and emodin on grass carp, companying by a notable reduction in malondialdehyde content. Modulation of antioxidant response by β-glucan, inulin and emodin supplementation was to activate Nrf2 signaling pathway and up-regulate the expression of antioxidant genes including catalase and copper/zinc superoxide dismutase. Additionally, TLR4 signaling pathway was notably inhibited by three additive diets, and the transcription level of pro-inflammatory cytokines like IL-1β, TNF-α, and/or IL-6 was dramatically suppressed in intestine tissue simultaneously. Afterward, an enhancement of intestinal barrier function was observed in fish fed β-glucan, inulin and emodin by inducing the overexpression of junction proteins such as Occludin, ZO3, ZO1, and/or ZO2. The above results documented that diet with β-glucan, inulin and emodin could exhibit beneficial impacts on the health of grass carp through the improvement in antioxidant capacity, suppression of inflammatory response, and enhancement of intestinal barrier function.

Drug research and development is a long-term and complicated process with the involvement of multidisciplinary, multi-sector cooperation and regulations of the Food and Drug Administration (FDA). It is of high risk, high cost, high benefit and time-consuming. Therefore, the drug administration and management is extremely necessary and useful. We discussed the whole process including laboratory study, target determination, drug discovery and screening, leading compound and optimization, preclinical and clinical trials, FDA approval and marketing. Actively exploring and applying modern administration and innovative management technology, we can scientifically and effectively enhance the discovery of new drug research and development, and strengthen the supervision of drug market. In recent years, innovation such as artificial intelligence has been applied to drug discovery and drug administration. We further analyzed the possibility of applying management technology to reduce risks, generate profits and benefit patients in the whole process of new drug research and development. In conclusion, drug administration and management plays critical roles in modern drug research and development, and the new technology can be helpful for drug launching.

This study introduces a circuit breaker flashover accident caused by lightning strokes in a row of Xingren convertor station in Guizhou. To find out the reason of the flashover and whether fault circuit breaker insulation coordination can meet requirements under multiple lightning strikes, the overvoltage condition of hot-standby circuit breakers under lightning surge is calculated and checked by using EMTP and full-scale high impulse voltage test of the fault circuit breaker is conducted for the first time. Owing to the hot-standby state of the circuit breaker, the flashover accident is more likely to happen when lightning surge invades the substation or convertor station again. Measures to improve the hot-standby circuit breakers’ lightning withstand level are proposed and by simulating analysis, the measure combined installing a line arrester at a tower of the inlet line and installing an arrester near a certain breaker on the line proves to be effective.

Phosphite is an important intermediate of the phosphorus cycle. Its life in environment is related to its oxidation rate. This paper investigated the photooxidation of phosphite in aqueous solution in the presence of ferric and oxalate ions under a Xe lamp. The photooxidation of phosphite followed pseudo-first-order reaction kinetics. The kinetics constant of 100 μmol L−1 phosphite was 0.0039 min−1 at pH 3 and Fe(III)/Ox 10.0/100.0 μmol L−1. The photooxidation was dependent upon the pH value, phosphite/ferric/oxalate concentration, and light intensity. The decrease of phosphite coincided with the increase of phosphate. The addition of 2-proponal, NaN3 or furfuryl alcohol inhibited the photooxidation of phosphite, which indicated that the yielded reactive oxygen species played an important role in the oxidation of phosphite. The results contribute not only to predict the longevity of phosphite in the aqueous solutions, but also to understand the transfer of phosphite in P cycle.

A novel integrated scheme based on relationships exploration (RE) is presented for the online estimation of the relative voltage stability margin (VSM). The proposed scheme can select the optimal variables as input features for estimation by detecting the relationship between each operation variable and the relative VSM in a large data set. Each relationship is given scores by the maximal information coefficient (MIC) and the Pearson correlation coefficient (PCC). The variables selected for estimation are corresponding to the relationships highly ranked by MIC and PCC, including linear relationships and nonlinear functional ones. Some of the highly ranked relationships are shown, curve fitted and described from the perspective of power system operation. If the data of the selected variables are obtained online from the wide area measurement system (WAMS), the relative VSM can be online estimated based on the explored relationships. The integrated scheme using RE-based process is examined on a 21-bus test system and a practical 1648-bus system provided by the software PSS/E, and it presents acceptable estimation accuracy. The impacts of training set size, selected relationships' types, total number and ranks on estimation accuracy are analyzed. The robustness of the scheme to measurement errors and topology variation is studied.

Objective Effects of conventional and atypical antipsychotics on bone mineral density (BMD) and serum prolactin levels (PRL) were examined in patients with schizophrenia. Methods One hundred and sixty-three first-episode inpatients with schizophrenia were recruited, to whom one of three conventional antipsychotics (perphenazine, sulpiride, and chlorpromazine) or one of three atypical antipsychotics (clozapine, quetiapine, and aripiprazole) was prescribed for 12months as appropriate. BMD and PRL were tested before and after treatment. Same measures were conducted in 90 matched healthy controls. Results Baseline BMD of postero-anterior L1–L4 range from 1.04±0.17 to 1.42±1.23, and there was no significant difference between the patients group and healthy control group. However, post-treatment BMD values in patients (ranging from 1.02±0.15 to 1.23±0.10) were significantly lower than that in healthy controls (ranging from 1.15±0.12 to 1.42±1.36). The BMD values after conventional antipsychotics were significantly lower than that after atypical antipsychotics. The PRL level after conventional antipsychotics (53.05±30.25ng/ml) was significantly higher than that after atypical antipsychotics (32.81±17.42ng/ml). Conditioned relevance analysis revealed significant negative correlations between the PRL level and the BMD values after conventional antipsychotics. Conclusion The increase of PRL might be an important risk factor leading to a high prevalence of osteoporosis in patients with schizophrenia on long-term conventional antipsychotic medication. Copyright © 2014 John Wiley & Sons, Ltd. key words—conventional/atypical antipsychotics; bone mineral density; prolactin; schizophrenia

Phosphite, phosphate, glyphosate and aminomethylphosphonic acid (AMPA) in natural water were determined by two-dimensional ion chromatography system coupled with capillary ion chromatography (2D-CIC). After filtrated by a 0.22-μm filter membrane, 25 μL of samples was injected into the first dimensional analytical column (AS11-HC) for preliminary separation. According to the different retention times in the first dimension, the target ions were divided into two groups (one group was phosphite and phosphate, another group was glyphosate and AMPA), then switched to the second dimensional capillary column (MAX-100) for further separation and detection. The effluent flow rates were 0.38 mL min −1 in the first dimension and 0.01 mL min −1 in the second dimension with KOH gradient elution, respectively. The carbonate removal devices were employed. The external standard method was used in all instances to quantitatively analyze. The results showed that the detection limits ( S/N = 3) were 0.18 nM for phosphite, 0.073 nM for phosphate, 0.15 nM for glyphosate and 2.6 nM for AMPA. The relative standard deviations (RSD, n = 6) of peak area ranged from 2.7% to 4.6%. The recoveries ranged from 80.1% to 118.4%. The results demonstrated that coupled capillary system could afford the simple detection of trace materials in natural water with complex matrix.

The phototransformation of phosphite (HPO32−, H2PO3−, +3) from Lake Taihu water (THW) under natural sunlight was evaluated. No direct phosphite photoreaction was observed under sunlight. Suspended solids were shown to play important roles in the indirect photoreaction of phosphite in lake water. The phototransformation of phosphite followed pseudo-first-order reaction kinetics and the kinetics constants (k, d−1) decreased as: 0.0324 (original THW), 0.0236 (sterilized THW), 0.0109 (filtered THW) and 0.0102 (sterilized filtered THW). Original THW with 1 mmol L−1 NO3− added was used to simulate the phosphite removal in lakes with serious N pollution. The results showed that the phototransformation was accelerated (with k increased to 0.0386–0.0463 d−1), and sterilization or filtration shown little effect to the transformation, as the half-lives of phosphite drew closer. Under simulated irradiation in NO3− system, increasing NO3− concentration or decreasing pH value promoted phototransformation. The addition of Fe3+ or Fe2+ accelerated photooxidation, while the addition of Mn2+ or Cd2+ inhibited phototransformation. Br−, NO2− and HCO3− in environmental concentrations decreased phototransformation, and HCO3− showed the strongest inhibition. Suwannee River humic acid or Suwannee River fulvic acid strongly inhibited the photooxidation process, and the inhibiting effects varied with their structure. Phosphite photooxidation was strongly inhibited by adding isopropanol or sodium azide as reactive oxygen species (ROS) quenchers. Electron spin resonance analysis indicated that OH was a main oxidant produced in this system. The increased amount of phosphate coincided with the decreased amount of phosphite, which indicated that the transformation product of phosphite was phosphate. Phosphite is a considerable component of the P redox cycle in Lake Taihu.

Phosphite (H2PO3(-), HPO3(2-), +3 valence), a reduced form of phosphorus (P), has been widely detected in water environments. The role of phosphite in the P biogeochemical cycle has not been investigated systematically and quantitative results on phosphite fluxes are lacking. In this study, intact sediment core simulation was employed to measure the flux of phosphite at the sediment-water interface in northern Lake Taihu. Phosphite fluxes (μmol m(-2) d(-1)) ranged from -38.21±1.14 to 7.10±2.18, with an annual average of -4.72±10.40. On the whole, phosphite migrated from water into sediment and the sediment was primarily a sink. The highest seasonal negative phosphite fluxes (μmol m(-2) d(-1)) occurred in winter (-10.44±18.63), followed by summer (-8.04±5.61) and spring (-2.61±4.17). In autumn, phosphite flux was 2.20±4.07. Higher annual average negative fluxes of phosphite (μmol m(-2) d(-1)) appeared in site ZSB (-12.70±17.96), which contained the highest content of total soluble P. The average yearly migration of phosphite in Lake Taihu from water to sediment was estimated to be (4.04±8.88)×10(6) mol y(-1). The transfer of phosphite from water into sediment usually occurs in winter may due to the season's natural tendency to create more favorable conditions for phosphite biogeochemical reactions. Phosphite fluxes showed significant negative correlations with the original phosphite concentration in water (r=-0.840, p