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Deep rock is under a complex geological environment with high geo-stress, high osmotic pressure, and strong dynamic disturbance, under the action of the three, the rock body is more prone to damage and rupture, inducing sudden water surges, seepage, blowouts and other engineering geologic hazards. Therefore, investigating the rock dynamics of the rock under hydraulic-mechanical coupling is one of the prerequisites for conducting rock engineering construction. In recent years, many scholars have obtained some fruitful research results in the study of rock dynamics properties under the consideration of water and different stress states. In order to provide more comprehensive guidance for engineering construction and facilitate the subsequent research, the above work is reviewed and summarized in terms of experimental setups, test results, and the mechanism of the confining pressure and water content. Firstly, the basic principle of the split Hopkinson pressure bar (SHPB) system and the device improvements used to simulate the deep rock storage environment are introduced, including the confine-ment-coupled SHPB system and pore-pressure (osmotic pressure)-coupled SHPB system. The advantages and shortcomings of each type of device in the study of rock dynamics under hydraulic-mechanical coupling are briefly analyzed. Secondly, the dynamic mechanical response characteristics of rocks hydraulic-mechanical coupling considering different stress states (uniaxial confining, triaxial confining) are summarized. The dynamic mechanical response of deep rocks under fixed preset pore pressure and osmotic pressure coupling and its law of variation with pore water pressure and osmotic pressure are described in detail. Subsequently, the mechanism of confining pressure on the dynamic properties of the rock is outlined, and the influence law under different stress states is analyzed. The strengthening and weakening microscopic mechanism and quantitative expression of the dynamic mechanical properties of the rock by water are recapped. Finally, the dynamic response of deep rocks under hydraulic-mechanical coupling is summed up, and the further experimental research work and the research direction of deep rock dynamics are proposed.

Objective: This study aimed to investigate the protective effect and underlying mechanism of a combined glutamine and curcumin formulation on ethanol-induced gastric mucosal damage in rats. Method: A total of fifty SPF-grade healthy SD male rats were randomly partitioned into five groups: A normal group, a model control group, a cimetidine group, a high-dose treatment group, and a low-dose treatment group. After a period of 30 days marked by oral gavage administration, all groups, with the exception of the normal group, were euthanized post anhydrous ethanol-induced modeling. The histopathological alterations in the gastric mucosa were observed via hematoxylin & eosin (H&E) staining. Furthermore, serum levels of malondialdehyde (MDA), nitric oxide (NO), and glutathione peroxidase (GSH-PX) were ascertained using a specific reagent kit. Concurrently, the concentration of prostaglandin E2 (PGE2) within the tissue and the expression levels of heme oxygenase-1 (HO-1), NADPH quinone oxidoreductase (NQO1), the antioxidant-related nuclear factor-E2-related factor 2 (Nrf2) gene, and glycogen synthase kinase-3β (GSK-3β) were evaluated. Results: In the cimetidine and high-dose treatment groups, the incidence of gastric mucosal bleeding and other forms of injury were noticeably mitigated (P

The research and application of gob-side entry retaining (GER) technology in Chinese coal mines has been over 60 years. Two major technical types including GER with filling and GER with roof cutting were developed. However, due to the complex mining and geological conditions of the mined-out coal seam in different mining areas, as well as the strong mining pressure behaviours in the retained roadway, the promotion and application of GER technology presented ups and downs. Firstly, the achievements and key technological advances in the main GER types in China, the principle of surrounding rock stability, road-in support technology, roadside support technology, adaptability evaluation and surrounding rock stability monitoring are summarized, and the application applicability of different technologies at this stage is analyzed. Then, the difficulties and challenges faced by current GER technology are summarized: there is still no systematic theory for GER with strong mining pressure; there are still shortcomings in the theoretical understanding of the interaction mechanism between the surrounding rock and the support body for GER with filling; the mechanical and deformation characteristics of the filling materials for the roadside support body are not yet suitable for GER in deep working faces or with strong mining pressure; the mechanism and control technology of floor heave for GER are not yet perfect; the research on stability control of filling body for GER under strong dynamic load or rock burst is still in a blank. Finally, concerned with such difficulties and challenges, several reserve technologies have been proposed: the coordinated control of controlled roof cutting and filling for GER in fully mechanized caving/ full-seam mining in the thick coal seam, and the GER technology with additive modified high-water materials in working faces with strong mining pressure; finally, a set of intelligent inversion workflow for rock mechanical parameters used in GER numerical simulations for GER is established, and an intelligent optimization design method for GER support parameters is proposed.

In order to explore the distribution rules of caving zone and water conducted zone of lower layer coal under the influence of mining on upper layer coal, based on theoretical analysis, distribution rules of floor fracture zone of upper coal layer and caving zone and fracture zone of overlying rock of lower coal layer with various of layer spacing have been simulated. Taking actual working face as background, the height of caving zone and fracture zone of overlying rock have been measured by using double-ended water stopper. The results show that the height of the caving zone of No.9+10 coal is 10.6 m, and the height of the fracture zone is 45.79 m. The mining of the upper coal seam has a certain influence on the development height of the fracture zone of the lower coal seam, and there is a negative correlation trend. The fracture zone of the upper and lower coal seams may be connected.

In this study, the flavonoids in peony seed meal were separated and purified by microfiltration-nanofiltration secondary membrane separation method. The effects of material-liquid ratio, extraction temperature, ethanol volume fraction and extraction time on the extraction amount of total flavonoids were investigated by single-factor experiments, and the extraction process was optimized and validated by response surface methodology on the basis of single factors. Eight types of microfiltration membranes, including polyvinylidene fluoride (PVDF), polyethersulfone (PES), polytetrafluoroethylene (PTFE), polypropylene (PP), mixed cellulose (MCE), polyacrylonitrile (PAN), aqueous acetate (CA) and polyamide (PA), were selected for the primary separation of PSMF extracts. The nanofiltration membranes were homemade organosilicon/PA composite membranes in the laboratory. The results showed that the optimum extraction conditions for PSMF were 1:15 g/mL, 50 ℃, 70% ethanol volume fraction, 30 min, (240.28±2.25) μg/mL of PSMF extraction amount. The PA membrane had a better separation effect, and the composite membrane had a better purification effect on PSMF, and the water solubility of flavonoids was increased to more than 90% after separation. After calcination at 800 ℃, the residual mass of the raw material solution was 1.43% and that of the PA membrane separation was 0.76%, and the BTESE/PA composite membrane was reduced to 0.26%, with fewer impurities and higher purity. Comparing its antioxidant activity before and after separation, the ·OH, DPPH· scavenging rate and reducing power were improved after separation, and the O2−· scavenging rate decreased from 79.94% to 64.82%. In this study, the active components in peony seed meal were analyzed. PSMF would be a novel phytoflavonoid resource with rich composition and certain research space.

Using hulled hemp seed powder as raw material, nitrogen was introduced to produce positive pressure cavitation, which realized the effect of accelerating the protein extraction rate. Taking the yield of protein as the evaluation index, the effects of pH, temperature, time, material-liquid ratio and aeration on protein extraction rate were explored by combining univariate test and response surface test. Results showed that, the optimal process conditions for nitrogen-assisted positive pressure cavitation extraction of hemp seed protein were as follows: The material-liquid ratio was 1:50 (g/mL), the pH was 12, the extraction temperature was 52 °C, the extraction time was 50 min, and the nitrogen ventilation was 1.6 L/min, under these conditions, the protein yield was 76.03%±1.64%. It was significantly higher than the magnetic stirring method under the same conditions by 56.32%. The physicochemical properties of hemp seed protein extracted by four methods (positive pressure alkaline solubility, magnetic alkaline solubility, positive pressure enzymatic hydrolysis, and magnetic enzymatic hydrolysis) were compared, and the results showed that the foaming and oil-holding properties of the proteins by magnetic alkalinity solution method were the strongest, 145% and 246%, respectively. There was little difference between water holding capacity and emulsification of the four methods. The protein denaturation temperature of the four extraction methods was compared, and the termination temperature of protein denaturation of the positive pressure alkaline solution method was 105.5 ℃, which was 4~13 ℃ higher than the other three methods. Hemp seed protein treated by positive pressure enzymatic hydrolysis contains 17 amino acids and an EAA/TAA score of nearly 40%, which was very in line with the FAO/WHO recommendation for high-quality protein. Experiments showed that nitrogen-assisted positive pressure cavitation could increase the extraction rate of hemp seed protein and had good physicochemical properties.

The resistance to melting is an important indicator of the quality of ice cream. During transport, storage and distribution, poorly melting resistance ice cream will inevitably become deformed due to fluctuations in ambient temperature, which in turn will affect the consumer experience, product sales and even the brand's reputation. Stabilisers are crucial to the melting resistance of ice cream. This paper reviews the mechanisms of stabilisers on ice cream melting resistance, the properties of different anionic/non-ionic stabilisers and their mechanism of actionon ice cream resistance, mainly in terms of gel formation, inhibition of ice crystal growth and enhancement of ice cream serum phase viscosity. Furtherly, it provides theoretical guidance for the development of cultural and creative ice cream, ice cream with complex structure and ice cream circulation.

To obtain high-quality walnut meal protein, the process conditions for extraction of walnut meal protein by alkaline solubilization and acid precipitation method and purification of walnut meal protein by glycolytic enzyme were optimized by single-factor experiments and response surface method, respectively, and the functional properties such as solubility, water absorption, and emulsification were analyzed. The optimal extraction process conditions were: pH12, temperature 55 ℃, time 90 min, and material-liquid ratio 1:40 g/mL. Under these conditions, the extraction rate of walnut meal protein could reach 81.89%±1.64%, and its settling point was pH4.5. The optimal purification process conditions were: pH4.5, material-to-liquid ratio 1:40 g/mL, enzymatic digestion time 129 min, enzymatic digestion temperature 53°C, and enzyme addition 0.4%. The purity of walnut meal protein purified under these conditions could reach 94.48%±1.83%. The results of functional properties of walnut protein showed that its solubility was 24.82%, water absorption 3.06 g/g, oil absorption 3.15 g/g, emulsification 16.10 m2/g, emulsification stability 38.87 min, foaming 30.53% and foaming stability 75.44% under the same pH conditions, and the purified walnut protein had better functional properties.

In this study, the culture medium of a recombinant Pichia kudriavzevii M48 overexpressed MET14 gene with high cadmium resistance and cadmium removal rate was optimized. Taking the comprehensive value of cadmium removal rate and biomass as the evaluation index, the medium composition was optimized through single factor test, 25-1 fractional factorial design and central composite design, so as to provide a research basis for making the recombinant strain M48 into cadmium removal preparation in the later stage. The results showed that the optimal medium was 23.42 g/L glucose, 27.72 g/L yeast extract and 2.04 g/L of potassium dihydrogen phosphate. Under these conditions, the cadmium removal rate of M48 was 79.63% and the biomass was 9.95 g/L, which were 2.70 and 1.16 times higher than that before optimization, respectively. Therefore, the cadmium removal rate and biomass of recombinant strain M48 were effectively increased by optimizing the medium composition.

In recent years, due to the influence of human activities and global warming, the coral reef ecosystem in the South China Sea (SCS) has degraded, and bleaching occurs. Utilizing the remote sensing method to monitor and understand the bleaching status of coral reefs is of great value to the protection and management of the ecological environment in the SCS. This study first obtains coral reef bleaching alert areas (BAAs) through multiperiod sea surface temperature data (SST) and selects the Antelope Reef in the Yongle Atoll of the Paracel Islands as the research area. Then, a new coral reef bleaching monitoring model is proposed, which uses water depth correction, coral reef classification, reflectance adjustment and threshold selection to carry out multitime series coral reef bleaching monitoring research with Landsat-8 remote sensing images from 2013 to 2018. The results show that the model can effectively obtain coral reef bleaching areas and provide a feasible approach for the monitoring of coral reef bleaching in the South China Sea.

Irritable bowel syndrome (IBS) is a common gastrointestinal disease. The main clinical symptoms are abdominal pain, bloating, abnormal defecation frequency and character. The pathogenesis of the disease is complex, including genetic factors, dietary differences, gut microbiota changes, gastrointestinal infection and brain-gut axis dysfunction. The main way to relieve IBS mainly focus on dietary restriction, including low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) diet, low advanced glycation end products (AGEs) diet, gluten-free diet and low lactose diet, which can effectively improve abdominal discomfort symptoms of IBS patients. This article summarizes the research status quo of domestic and foreign scholars for IBS in recent years, including the pathophysiological mechanism of IBS, the relationship between dietary patterns and IBS intestinal flora, quantitative detection methods for FODMAPs components and AGEs in food. Food processing technologies are also introduced to reduce the content of FODMAPs and AGEs in food, in order to provide healthy and effective dietary intervention strategies for IBS patients.

ObjectivesThe cohesive zone length is the sum of the cohesive element length at the failure edge and the lengths of the other cohesive elements connected to it. The cohesive zone length determines the maximum size of the mesh. Therefore, the accurate estimation of cohesive zone length and reasonable mesh division are important factors affecting calculation accuracy. MethodsBased on several J-integral assumptions and existing research results, a modified function on length thickness ratio value is added to the original formula. The modified formula is then applied to an ice mechanics model. Based on the finite element method, a model of a double cantilever beam is established to verify the accuracy of the formula through comparison with the experimental results.ResultsThe results show that there must be at least four cohesive elements in a cohesive zone length to describe the fracture process accurately. This conclusion is also applied to the numerical simulation of a three-point bending experiment. The error of the limit load is 2.9%, and that of the fracture point is within a reasonable range.Conclusion It is concluded that the modified cohesive zone length formula is more suitable for ice materials.

Laodong Zhai Lead-zinc deposit is located in Danzhai County, Guizhou Province. Lead-zinc ore bodies mainly occur in the Sinian Doushantuo Formation (Pt3d). In this paper, the process mineralogy of Laodong Zhai Lead-zinc deposit was studied by means of chemical analysis, microscope analysis, X-ray diffraction and electron probe analysis. The results show that the content of sphalerite and galena is 15.02% and 0.81% respectively , in raw ore comprehensive sample. Gangue minerals are mainly quartz (56.21%), followed by Muscovite (15.2%), kaolinite (6.55%), and a small amount of dolomite, calcite and so on. The main carrier minerals of Pb and Zn are galena and sphalerite, with theoretical recovery rates is 98.60% and 87.90%, respectively.

In order to study the influence of the surface structure of full-bore porous glass on its sound absorption properties, the surface was punched twice, the influence of surface structure parameters on the sound absorption properties of full-bore porous glass was analyzed by orthogonal test. the best structural parameters of the sound absorption sample was obtained. The results show that the change of the surface structure of the porous material has a great influence on the sound absorption property, but has little effect on the initial frequency. The factors affecting the sound absorption properties of porous glass materials are material thickness, porosity, hole diameter and hole depth. The best design parameters of the porous glass are as follows: the porosity is 0.76, the thickness 20 m, the hole depth 0.5 times the thickness of the sample, and the pore diameter 2.2 mm. At this time, the average sound absorption coefficient of porous glass is as high as 0.82, an increase of 24.6%.

Objective To analyze the relationship between dietary intake of n-3 polyunsaturated fatty acids (n-3 PUFA) and the incidence of type 2 diabetes mellitus (T2DM) among residents in selected districts of Chongqing, and to provide recommendations for the prevention of T2DM. Methods Using cross-sectional survey data collected in Chongqing as part of the 2021 China National Nutrition and Health Survey (CNNHS), and in combination with energy and nutrient intake calculated from the Chinese Food Composition Tables, single-factor and multi-factor Logistic regression models were employed to investigate the association between n-3 PUFA intake and the incidence of T2DM. Results This study included a total of 1 511 participants, of which 280 were diagnosed with T2DM, accounting for 18.80% of the total. When compared to participants in the lowest quartile of animal-derived n-3 PUFA intake, those in the highest quartile had a significantly lower risk of developing T2DM (OR = 0.61, 95% CI: 0.42-0.88). The results from adjusted Model 1 were consistent with those of Model 2 (Model 1: OR = 0.64, 95% CI : 0.44-0.94; Model 2: OR = 0.66, 95% CI: 0.44-0.98). Notably, in Model, the risk of developing T2DM was even lower in the Q4 group of plant-derived n-3 PUFA compared to Q1 (OR = 0.48, 95% CI: 0.24-0.98). Conclusion The dietary intake of animal-derived n-3 PUFA and plant-derived n-3 PUFA is negatively correlated with the incidence of T2DM. The association between animal-derived n-3 PUFA and T2DM weakens after adjusting for confounding factors, with the highest quartile of plant-derived n-3 PUFA showing the strongest protective effect against T2DM. [ABSTRACT FROM AUTHOR]

BackgroundThe occurrences of occupational stress and sleep disorders are closely related. As a high-risk group of occupational stress, the sleep quality of locomotive engineers is of great significance for road traffic safety. ObjectiveTo explore the direction and degree of occupational stress affecting the sleep quality among locomotive engineers, and to analyze potential mediating and moderating roles of response strategy and overcommitment in the relationship. MethodsFrom July 1st to July 31st, 2022, a total of 6219 locomotive engineers from three locomotive depots of China Railway Lanzhou Group Corporation were selected. We conducted an online survey on occupational stress, overcommitment, response strategy and sleep quality using the Effort-Reward Imbalance, Personal Resources Questionnaire, and Pittsburgh Sleep Quality Index. Single factor analysis and correlation analysis were conducted using SPSS 25.0 software, mediation and moderation models were constructed using the Process V3.3 macro program plugin, and Harman's single factor test was used for common method bias testing. ResultsA total of 6219 questionnaires were distributed, and 5738 valid questionnaires were collected, with an effective response rate of 92.27%. The average locomotive engineers' occupational stress score (1.22±0.29), overcommitment score (16.38±3.55), response strategy score (50.00±10.00), and sleep quality score (11.51±3.95) were calculated. The Pearson correlation analysis results showed that occupational stress was positively correlated with overcommitment and sleep quality (r=0.435, 0.321, P

In advanced high-speed fiber optic communication systems, due to the introduction of dense wavelength division muliplexing technology, the signal spectral interval is getting narrower and narrower, and the traditional out-of-band Optical Signal-to-Noise Ratio (OSNR) monitoring technology is no longer accurate. Therefore, further study is required in the low-cost n-band OSNR monitoring scheme. A Deep Neural Network (DNN) link OSNR monitoring scheme for Intensity-Modulation and Direct Detection (IMDD) system is proposed. We used a 5-layer DNN trained from 550 000 datasets to successfully estimate the OSNR of the 2 GBaud On-Off Key (OOK) signal in the range of 5 to 15 dB, and the Mean Absolute Error (MAE) is less than 0.8 dB. [ABSTRACT FROM AUTHOR]

The Kulagangri Dome is located at the eastern part of the Himalayan metallogenic belt. Based on the 1 :50 000 mineral geological mapping and sparse surface engineering, the Gabo pegmatite-type lithium deposit was firstly found at the eastern part of the Kulagangri Dome. Ore-bearing spodumene pegmatite dikes are generally hosted by the marble in the middle unit of the dome, with length ranging from 1 m to 1 200 m, and width ranging from 0. 8 m to 40 m. The main lithium containing minerals in the spodumene pegmatite are spodumene, elbaite and lepidolite. At present, two main Li mineralization zones are controlled by 5 surface engineering. The mineralization zone I is about 2 km long, and includes 2 main orebodies (K1 and K2). The mineralization zone II is about 700 m long, and include one main orebody (K3). The K1 orebody is about 1 200 m long and 5 ~ 40 m thick, with an average thickness of about 20 m. The K2 and K3 orebodies occur as the large lenticular shape, with strike extension >100~600 m and thickness 15~50 m. The total thickness of K2 orebody is 45. 3 m. The average grade of Li2O, Rb2O and BeO is 1.11%, 0.064% and 0.047%, respectively. The newly discovered Gabo lithium deposit is dominated by Li, Be and Rb, associated with Nb, Ta, Cs, W and Sn. Based on the geological survey results, the Gabo lithium deposit is large in scale, and showing considerable potential for further prospecting in the area. The discovery of Gabo lithium deposit is another breakthrough in the exploration of rare metals in the Himalayan metallogenic belt, which is of great significant role in further understanding of the tectono-magmatic evolution and rare metal mineralization in the Cenozoic Himalaya, and further enriching the theory of collisional orogenesis and mineralization in the southern Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]

To study the efficiency of flue gas sequestration with enhanced shale gas recovery in quartz slit, Grand Canonical Monte Carlo (GCMC) and Molecular Dynamics (MD) simulations were adopted to investigate the influence of burial depth, formation water content and the injection ratio of flue gas on the recovery efficiency of shale gas (CH4) in quartz slit by flue gas (CO2/N2). The density distribution, loading, adsorption heat and interaction energy of each component were systematically analyzed to reveal their adsorption mechanisms and the recovery efficiency of CH4. It indicates that the loadings of mixed CH4 and N2 (ΓCH4 and ΓN2) exhibit negative correlation with formation water content. With the increasing burial depth, both ΓCH4 and ΓN2 increase at first and then tend to be constant when the burial depth is over 2 400 m. The maximum loading of CO2 (ΓCO2) occurs at the burial depth of 2 400 m. There is a positive correlation of ΓCO2 with formation water content when the burial depth is below 2 400 m, and a negative correlation when the burial depth is over 2 400 m. The recovery efficiency of CH4 (η) reaches the maximum point at the burial depth of 400-600 m, which increases with the increasing mole fraction of CO2 in flue gas, showing that CO2 in flue gas can promote the displacement of CH4 significantly.

A research was done to study the Pb adsorption by the root cell wall of tea plant extracted from Longjing 43. It was indicated that the amount of Pb adsorbed by the root cell wall increased with augment of the initial pH of the solution under acidic condition, dramatically as the pH ranged from 2. 0 to 4. 5. The amount of Pb increased with the Pb concentration in the solution at pH 4. 5, which could be well fitted by the Freundlich adsorption model. The adsorbed Pb reached 9.7 mg ∙ g-1 under equilibrium condition, 90% of which was adsorbed in 320 minutes, while 50% was desorbed in 60 minutes based on the desorption dynamic curve. The kinetics of both adsorption and desorption could be well described by a second-order rate equation. The amount of absorbed Pb by the root cell wall varied after modified treatments, reducing by 51. 1% after esterifing, 41. 3% with pectinase, and 10. 8% via aminomethylation, suggesting that carboxyl, galacturonic acid, pectin and amino, to some extent, all took part in the Pb adsorption by the root cell wall. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) are the typical persistent organic pollutants (POPs) in the environment. As a ubiquitous attenuation course of chlorinated organic compounds in anoxic environment, the microorganism-mediated reductive dechlorination process plays an important role in PCBs transformation, especially the transformation of higher chlorinated PCBs. The higher chlorinated PCBs can be dechlorinated in anaerobic condition, and thus, their persistence and toxicity can be decreased. The resultant lower chlorinated PCBs from the dechlorination can be further degraded and completely mineralized in aerobic condition. This paper summarized the research advances of PCBs microbial reductive dechlorination, introduced the mechanisms and characteristics of the dechlorination and the related specific microorganisms, and approached the affecting factors of PCBs bio-dechlorination, as well as the significances of anaerobic dechlorination coupling with aerobic degradation. The future research directions, including the complex metabolic networks of dechlorinating microbial populations, the screening of novel specific dechlorinators and their practical applications in the remediation of PCBs contaminated sites were also prospected. [ABSTRACT FROM AUTHOR]

Persistent organic pollutants have increasingly become a critical environmental concern, while thermophiles have the high potential of degrading various kinds of environmental organic pollutants. At high temperatures, thermophiles have higher metabolic activity, and the competition by mesophiles is reduced, meanwhile, the solubility and bioavailability of some persistent organic pollutants are greatly increased, and thus, the degradation of the pollutants by thermophiles is more rapid and complete. Therefore, thermophils are of great significance for the bio?treatment of organic wastewater and the bioremediation of organic pollutants?contaminated sites. This paper introduced the research progress on the degradation of organic pollutants by thermophiles in terms of the characteristics of thermophiles in degrading organic pollutants, the effects of temperature on the degradation, the degradation pathways, the degradation enzymes, their coding genes, and practical engineering applications. The future research directions including the degradation mechanisms of thermophiles, their resources reserve, related technology strategies and their applications were also prospected. [ABSTRACT FROM AUTHOR]

Soil microbial indicator is one of the important biological indicators in evaluating the extent of soil contamination. In recent years, with the development of molecular biology, many studies have focused on the ecological functions of soil microorganisms by using metagenomics, metatranscriptome and metaproteomics. Relative to metagenomics and metatranscriptome, soil metaproteomics aims to investigate the spatial and temporal changes of the proteins extracted from soil as well as the functional components of soil microbial genomic expression products, which is more conclusive to explore the ecological functions of soil microbes and their roles in soil pollutants transportation and transformation. Therefore, soil metaproteomics has great potential in soil pollution assessment. Currently, soil metaproteomics is still at its infancy stage, while soil protein extraction method is one of the key factors restraining the potential application of soil metaproteomics. In this paper, the advantages and disadvantage of soil metaproteomics in soil pollution assessment were reviewed, with the focus on the comparison of different soil protein extraction methods. In combining with case studies, the feasibility and limits of soil proteins as an indicator for soil pollution assessment were analyzed. In addition, the future research perspectives on the development of soil metaproteomics were discussed. [ABSTRACT FROM AUTHOR]

Activated sludge process is widely used in treating a wide variety of wastewater, but the by-product is the large amount of excess sludge. To treat the excess sludge properly could spend 25%-60% of the total cost of wastewater treatment, while improperly treating the sludge could cause serious secondary pollution. Therefore, the reduction of excess sludge is becoming a rising challenge. Using thermophiles to degrade excess sludge is a way easy in operation and inexpensive in maintenance, being a promising method in application. This paper reviewed the recent progress in the researches of sludge-degrading thermophiles, their working mechanisms, and the enzymes from thermophiles, such as thermophilic proteolytic enzymes and thermophilic lipases which play an important role in the degradation of sludge. The factors affecting the degradation of sludge by thermophiles were summarized, and the perspectives for the further research on the application of thermophiles in digesting sludge were discussed. [ABSTRACT FROM AUTHOR]

Solid state phosphorous is an important phosphorus speciation controlling the phosphorous bioavailability and mobility in the environment. Synchrotron-based X-ray absorption near-edge structure ( XANES) spectroscopy, with its unique advantage of being a non-destructive method in identifying the local chemical information of target element at molecular level in situ, has become one of the frontier technologies for characterizing the speciation of chemical substances and clarifying the microscopic mechanisms of chemical reactions, attracting extensive attention in the field of environmental chemistry. This paper briefly introduced the basic theory of phosphorus XANES spectroscopy , summarized the applications of XANES spectroscopy in the researches of solid state phosphorus speciation in minerals, soils, and organic fertilizers, and analyzed the challenges and prospects of the applications of XANES spectroscopy in identifying the solid state phosphorus speciation in the environmental samples. It was pointed out that XANES spectroscopy should combine with other microscopic spectroscopic techniques and macroscopic analytical methods, complementing each other, to provide a comprehensive and effective technical support for the research of the speciation characterization and transformation mechanisms of phosphorus in the environment. [ABSTRACT FROM AUTHOR]

A hydroponics experiment combined with subcellular fractionation and sequential extraction was conducted to study the Pb concentration in different organs of two tea plant varieties (Longjing 43 and Yingshuang) and the Pb subcellular distribution and chemical forms in the roots of the varieties. Under Pb stress, the root system of the two varieties had different features in morphology. With the increasing concentration of Pb in culture solution, the Pb concentration in Longjing 43 young leaves increased, but that in Yingshuang爷s had no significant variation. A marked difference was observed in the Pb subcellular distribution and its chemical forms in roots between the two varieties under Pb stress. In Longjing 43 roots, all subcellular fractions except soluble ones had a lower Pb concentration at low Pb stress, and all the subcellular fractions except cell wall ones had a higher Pb concentration at higher Pb stress, compared with those in Yingshuang爷s. In Longjing 43 roots, the HAc鄄extractable Pb occupied the greatest proportion, followed by NaCl鄄extractable Pb, HCl鄄and H2O鄄extractable Pb, and ethanol鄄extractable Pb; while in Yingshuang爷s, NaCl鄄extractable Pb had the greatest proportion, followed by HAc鄄extractable Pb, HCl鄄and H2O鄄extractable Pb, and ethanol鄄extractable Pb. Based on these findings, tea plant variety Yingshuang was likely to possess a higher tolerance to Pb than Longjing 43 did. [ABSTRACT FROM AUTHOR]

Taking non-transgenic parental rice as the control, and by using 13C pulse-chase labeling method coupled with phospholipid fatty acid (PLFA) analysis, this paper studied the effects of transgenic Bt rice on the here soil. The results showed that in the rhizosphere soils of transgenic Bt rice and its non-transgenic parent, saturated PLFAs and branched PLFAs were the main, followed by monounsaturated PLFAs, and polyunsaturated PLFAs. A significantly lower amount of Gram-positive bacterial PLFAs and a higher amount of Gram-negative bacterial PLFAs were observed in the rhizosphere soil of transgenic Bt rice at its seedling, booting, and heading stages, as compared with the control. In the whole growth ?period of rice, transgenic Bt gene had no significant effects on the fungal and actinomycete PLFAs in rhizosphere soil, and no significant difference was observed in the rhizosphere soil 13C-PLFA content between transgenic Bt rice and its non-transgenic parent. These findings indicated that the insertion of exogenous cry1Ab gene into rice only had temporary effects on the microbial community composition in the rhizosphere soil of rice. [ABSTRACT FROM AUTHOR]

Persisters are a group of special subpopulation of bacteria, only occupying <0-1% of the whole population but having the characteristics different from the ordinary bacteria and resistant mutants. They have complex formation mechanism, and are difficult to isolate and culture. The persisters can adapt to the adverse environment via "dormancy-growth-proliferation-to maintain their survival and cell structure stability, and play a vital role in the multi-drug and multi-metal tolerance of microbial biofilm, being of great significance in maintaining the stability of microbial community structure. This paper reviewed the research progress on the characteristics of persisters, their gene regulation mechanisms, and their effects on the multi-drug and multi-metal tolerance of microbial biofilm. The related research directions in the future were also prospected. [ABSTRACT FROM AUTHOR]

As the first step of nitrification, ammonia oxidation is the key process in global nitrogen biogeochemical cycling. So far, the autotrophic ammonia-oxidizing bacteria ( AOB) in the β- and 7-subgroups of proteobacteria have been considered as the most important contributors to ammonia oxidation, but the recent researches indicated that ammonia-oxidizing archaea ( AOA) are widely distributed in various kinds of ecosystems and quantitatively predominant, playing important roles in the global nitrogen biogeochemical cycling. This paper reviewed the morphological, physiological, and ecological characteristics and the molecular phylogenies of AOA, and compared and analyzed the differences and similarities of the ammonia monooxygenase ( AMO) and its encoding genes between AOA and AOB. In addition, the potential significant roles of AOA in nitrogen biogeochemical cycling in aquatic and terrestrial ecosystems were summarized, and the future research directions of AOA in applied ecology and environmental protection were put forward. [ABSTRACT FROM AUTHOR]

Phosphorus (P) release from sediments is one of the most important causes of lake eutrophication, while the activity of P is determined by P chemical form. Due to its advantages in improving our knowledge about the P fractions in environmental samples, the 31P nuclear magnetic resonance (31P NMR) technology has received extensive attention. This paper summarized the current studies on the characterization, translocation, and transformation of P fractions in sediments by using this technology, and described the technical principles, classification, analytical procedures, and specific application fields of this technology. At present, the researches of sediment P by using 31P NMR technology were focused on the characterization of different P forms, the effects of microbes on the P translocation and transformation, and the quantitative analysis of different P fractions. The studies on the P-extracting agents and extraction methods were the hot topics as well. The potential issues and research trends about the application of 31P NMR technology in environmental samples were also discussed. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to study the microbial activity and community structure in a lead-polluted paddy soil under effects of amendment with different concentration sodium thiosulfate. The amendment of the sulfur-containing substrate increased the soil oxidation-reduction potential and respiration rate, promoted the growth of soil sulfur-oxidizing bacteria, and induced some changes in soil microbial community structure. The clone sequencing indicated that the specific bands of soil microbes in sodium thiosulfate treatments had very high similarity to Bateroidetes, Thiobacillus, β-proteobacteria, and Acidobacteria. Significant changes were observed in the contents of soil carbonate- and Fe/Mn oxide- bound Pb after the amendment of sodium thiosulfate. [ABSTRACT FROM AUTHOR]

Laboratory simulation tests were conducted to examine the effects of different washing reagents (distilled water, HCl, H3PO4, oxalic acid, and CaCl2) in extracting the heavy metals from contaminated soils left by a chemical plant. The effects of reagent concentration, reaction time, and washing time on the washing efficiency were investigated, and the form variation of test heavy metals was determined before and after HCl washing. Distilled water, H3PO4, and CaCl2 could remove less than 1% of most heavy metals, and the highest removal rate was only 3.58%; while 2 mol HCl∙L-1could obtain the highest washing efficiency under the optimal conditions, i.e., soil:liquid ratio was 1:3, reaction time was 1 hour, and the soils were washed twice by HCl solution. The removal rates of Cr, Pb, Zn, Cu, and Cd from test soils were 80.75%, 88.69%, 98.00%, 79.33%, and 95.52%, respectively. Among the washing reagents, HCl could effectively remove all forms of heavy metals. [ABSTRACT FROM AUTHOR]

Landfill sites are the major sources of offensive odor in urban public facilities. With the progress of urbanization and the residents' demands for a higher living environment quality, the odor emission from landfill sites has become a severe pollution problem, and the odor control at landfill sites has been one of the research hotspots. This paper summarized the main components and their concentrations of the odor from landfill sites, and expatiated on the research progress in the in-situ control of the odor. The further research directions in in-situ control of the odor from landfill sites were prospected. [ABSTRACT FROM AUTHOR]

Tea waste is an important part of agricultural solid wastes,because of its various sources and huge amount. The heavy metals removal from waste water by tea waste has been paid much attention by the researchers around the world,owing to the adsorption characteristic of tea waste. In this paper,the research advances in the heavy metals removal from aqueous phase by tea waste were summarized from the aspects of affecting factors,adsorption mechanism,pretreatment,desorption,and regeneration,and the prospects were put forward. It was considered that for the industrialized utilization of tea waste absorbents, further researches should be focused on their adsorption mechanism,pretreatment,desorption and regeneration,technological parameters,and aftertreatment. [ABSTRACT FROM AUTHOR]

A 2-month fumigation experiment was conducted with opened top chambers to study the effects of different concentration (0.1, 0.5, and 4.0 microl · L-1) NO2 on the growth and photosynthesis of 1-year Cinnamomum camphora seedlings. Fumigation with 0.1 and 0.5 microl NO2 · L-1 promoted the growth of the seedlings, while with 4.0 microl NO2 · L-1 was in adverse. The diurnal variation of net photosynthetic rate (Pn) presented two-peaks, with an obvious depression in midday. 0.5 microl NO2 · L-1 increased the Pn, the maximum of Pn reached 8.542 micromol CO2 · m-2 s-1; 4.0 microl NO2 · L-1 decreased the Pn in most period of time; while the effect of 0.1 microl NO2 · L-1 varied with time period. Fumigation with 0.5 and 4.0 microl NO2 · L-1 increased the maximal and minimal values of stomatal conductance (Gs) and intercellular CO2 concentration (Ci), while 0.1 microl NO2 · L-1 increased the maximal and minimal values of Ci but decreased the maximal and minimal values of Gs. At the middle and late stages of fumigation, the mean Pn of the seedlings treated with 0.5 microl NO2 · L-1 was significantly higher than that treated with 0.1 and 4 microl NO2 · L-1. At the early stage of fumigation, 0.5 and 4.0 micro NO2 · L-1 significantly decreased the maximal PS II efficiency (Fv/Fm); and at the late stage, 4.0 μNO2 · L-1 still decreased the Fv/Fm significantly. [ABSTRACT FROM AUTHOR]

Biomass-derived black carbon, also named biochar, has the characteristics of high stability against decay and high capability of adsorption, and can affect the environment through its interactions with climate and geology, playing a significant role in global climate change, carbon biogeochemical cycle, and environmental system. In recent years, more and more researchers in the fields of atmospheric sciences, geology, and environmental science focused on the environmental behavior and effect of biochar. As one possible source of the components with high aromatic structure in soil humus, biochar is of great importance in increasing soil carbon storage and improving soil fertility, and in maintaining the balance of soil ecosystem. This paper offered the latest information regarding the characteristics and biotic and abiotic oxidation mechanisms of biochar, its effects on global climate change, and the environmental effect of biochar in soil. Research prospects were briefly discussed on the environmental behavior and effect of biochar in soil ecosystem. [ABSTRACT FROM AUTHOR]

The inhibitory effect of allelochemicals released by submerged macrophytes on ph ytoplankton is considered as one of the mechanisms that contribute to the stabilization of clear-water status in shallow lakes. This paper reviewed t he research progress in the allelopathy of submerged macrophytes on algae from t he aspects of the occurrence frequency and coverage of allelopathically active s ubmerged macrophytes in lakes, and the kinds and allelopathical effects of the a llelochemicals released from the macrophytes. The previous researches indicated that allelopathically active submerged macrophyte species such as Myriophyllum , Ceratophyllum, and Elodea were efficient to control phytoplankton, especially when their biomass was high enough, and the dominant algae were sensitive species. The allelochemicals such as hydroxybenzene released by the submerged ma crophytes could inhibit the growth of algae. Different phytoplankton species exhibited different sensitivity against allelochemicals, e.g., cyanobacteria and diatom were more sensitive than green algae, while epiphytic species were less sensitive than phytoplankton. Environmental factors such as light, temperature, and nutrients could significantly affect the allelopathical effect of submerged macrophytes. The research of the allelopathy of submerged macrophytes is still at its beginning, and further researches are needed on the effects of environmental factors on the allelopathy, extraction and identification of allelochemicals, selective algal control mechanisms, and metabolism of the allelochmicals. [ABSTRACT FROM AUTHOR]

Objective To investigate the clinical efficacy of disc repositioning surgery combined with orthodontic treatment in patients with temporomandibular disorder and facial asymmetry. Methods One patient who underwent disc repositioning surgery combined with orthodontic treatment for temporomandibular joint disorder and facial asymmetry was reported. Preoperatively, the patient had a skewed shape of the opening, mild pressure pain in the right preauricular region with left mandibular deviation, and a mismatch between the width of the upper and lower dental arches. In the arthrosurgery department, bilateral temporomandibular disc replacement and anchorage were performed through a transauricular incision, and an auxiliary splint was worn to stabilize the jaw position for 6 months. In the orthopedic department, maxillary skeletal expansion was used in combination with the multiloop edgewise archwire technique to reconstruct the occlusion after 16 months of orthodontic treatment. Results The deviation was corrected by wearing an occlusal splint for six months after joint repositioning and anchoring; moreover, the pain symptoms disappeared, and the cone beam CT examination showed that the bilateral temporomandibular joint space was uniformly enlarged, the lower alveolar ridge midline deviated to the right, the posterior regions of the teeth were bilaterally inverted, and the anterior region and the posterior region of the left side were open. The orthodontic treatment matched the width of the upper and lower dental arches and established the cuspal molar neutrality relationship and the normal overjet coverage of the anterior teeth; additionally, the mandibular position was not obviously skewed. A review of the results of the related literature shows that abnormal occlusal relationships, such as mismatched arch width and skewed occlusal plane, can cause adaptive mandibular deviation, which can lead to the occurrence of TMD. Temporomandibular joint disc anchorage with splint treatment can effectively improve maxillofacial deformity in young TMD patients. After the establishment of a stable, physiologically functional disc-condylar relationship, orthodontic treatment is required to remove the interfering factors to rebuild the occlusion, and long-term postoperative review and follow-up are needed. Conclusion In patients with TMD and mandibular accommodative deviation due to occlusal anomalies, establishing a normal disc-condylar relationship and eliminating occlusal interference through disc repositioning surgery combined with orthodontic treatment can effectively improve facial shape and establish a stable jaw position.

Objective To analyze the ability of micro-implant nails placed in different locations in the posterior region to improve the hard and soft tissues of the labiodental region in patients with gummy smiles to provide a reference for clinicians. Methods This study was reviewed and approved by the Ethics Committee, and informed consent was obtained from the patients. Thirty young female patients with anterior tooth protrusions and gummy smiles were included in the retrospective study; 18 patients had micro-implant nails implanted between the premolars (group A), and 12 patients had implant nails placed between the roots of the premolar and the molar and an intraoperatively placed rocking-chair archwire (group B). The preoperative and postoperative distances from the incisal end of the upper mesial incisors to the lower point of the upper lip (U1-Stms), the vertical distance from the incisal end of the upper mesial incisors to the palatal plane (U1-PP), the vertical distance from the point of the alveolar ridge to the palatal plane (Spr-PP), the distance from the incisal end of the upper mesial incisors to the point of the alveolar margin (U1-Spr), and the vertical distance from the point of the proximal middle buccal cusp of the maxillary first molar to the palatal plane of the maxillary first molar (U6-PP) were measured in the cephalometric lateral radiographs of the two groups; additionally, the amount of hard and soft tissues of the upper anterior region exposedduring smiling and the maximum amount of gingiva exposed during smiling were assessed from the smile photograph. Results After correction, the lip-dentition relationship improved significantly in both groups, with an average reduction of 2.6 mm in U1-Stms, 2.4 mm in U1-PP, 1.4 mm in Spr-PP, and 0.9 mm in U1-Spr in Group A. In group B, the U1-Stms was reduced by an average of 2.3 mm, the U1-PPs by an average of 1.6 mm, the Spr-PPs by 1.4 mm, and the U1-Spr by 0.2 mm. The difference between pre- and postoperative U6-PP in both groups was not significant (P>0.05). Group A had greater ∆U1-PP and ∆U1-Spr changes than group B(PP>0.05). The amount of soft and hard tissue exposed and maximum amount of gingiva exposed in the upper anterior region of the smile were reduced in 30 patients postoperatively, with group A having anaverage reduction of 70.19% of the preoperative amount of soft and hard tissue exposed in the upper anterior region and an average reduction of 24.12% of the preoperative maximum amount of gingiva exposed, and group B having an average reduction of 76.12% of the preoperative amount of hard and soft tissue exposed in the upper anterior region and an average reduction of 31.88% of the preoperative maximum gingiva exposed after the operation. The difference in the ratio between the two groups was not statistically significant (P>0.05). Conclusion For patients with proptosis and gummy smiles, placing micro-implant nails between the roots of maxillary premolars can effectively lead to retraction and intrusion of anterior teeth to improve the lip-dentition relationship and improve gummy smile, and placing micro-implant nails between the roots of the maxillary second premolar and the first molar together with the use of rocking chair arches can also achieve a good therapeutic effect.