Tanshinone IIA improves sepsis-induced acute lung injury through the ROCK2/NF-κB axis.

BACKGROUND: This research sought to explore the effects of Tanshinone IIA (TIIA) and its potential mechanism in sepsis-induced acute lung injury. METHODS: Cecal ligation and puncture (CLP) was performed to construct a sepsis model in vivo. RLE-6TN cells were treated with lipopolysaccharide (LPS) to establish a sepsis model for in vitro experiments. The histopathological changes of the lung tissues were scored using HE staining, IHC, and dry and wet method. Apoptosis in the lung tissues was detected by TUNEL assay. Meanwhile, ELISA was used to determine the levels of the pro-inflammatory factors. Cell proliferation and apoptosis were evaluated using CCK-8, EdU assays and flow cytometry, respectively. RT-qPCR analysis was carried out to measure the expression of Rho associated coiled-coil containing protein kinase 2 (ROCK2). RESULTS: TIIA dramatically alleviated the pathological injuries of the lung, and relieved apoptosis, neutrophil infiltration, lung edema and inflammation response. Highly expressed ROCK2 was observed in septic rats in vivo and LPS-induced RLE-6TN cells in vitro. We found that ROCK2 knockdown promoted cell proliferation, and inhibited cell apoptosis and inflammation in LPS-treated RLE-6TN cells. Moreover, TIIA improved LPS-caused injury in RLE-6TN cells through downregulating ROCK2 expression. Mechanistically, TIIA repressed LPS-caused activation of the NF-κB pathway by regulating ROCK2 in RLE-6TN cells. Additionally, TIIA assuaged CLP-induced lung injury in the rats via downregulating ROCK2 to inactivate the NF-κB pathway in vivo. CONCLUSION: Our data demonstrated that TIIA improved sepsis-induced lung injury by downregulating ROCK2 and further inactivating the NF-κB signaling pathway in vivo and in vitro.

Microbial keystone taxa drive crop productivity through shifting aboveground-belowground mineral element flows.

Unbalanced fertilization of nutritional elements is a potential threat to environmental quality and agricultural productivity in acid soil. Harnessing keystone taxa in soil microbiome represents a promising strategy to enhance crop productivity as well as reducing the adverse environmental effects of fertilizers, with the goal of agricultural sustainability. However, there is a lack of information on which and how soil microbial keystone taxa contribute to sustainable crop productivity in acid soil. Here, we examined soil microbial communities (including bacteria, fungi, and archaea) and soil nutrients, and the mineral nutrition and yield of maize subjected to different inorganic and organic fertilization treatments over 35 years in acid soil. The application of organic fertilizer alone or in combination with inorganic fertilizers sustained high maize yield when compared with the other fertilization treatments. Microbial abundances and community structures rather than their alpha diversities explained the main variation in maize yield among different treatments. Sixteen soil keystone taxa (a fungal operational taxonomic unit and 15 bacterial operational taxonomic units) were identified from the microbial co-occurrence network. Among them, five keystone taxa (in Hypocreales, Bryobacter, Solirubrobacterales, Thermomicrobiales, and Roseiflexaceae) contributed to high maize yield through increasing phosphorus flow and inhibiting toxic aluminum and manganese flow from soils to plants. However, the remaining eleven keystone taxa (in Conexibacter, Acidothermus, Ktedonobacteraceae, Deltaproteobacteria, Actinobacteria, Elsterales, Ktedonobacterales, and WPS-2) exerted the opposite effects. As a result, maize productivity varied among different fertilization treatments because of the altered maize mineral element flows by microbial keystone taxa. We conclude that microbial keystone taxa drive crop productivity through shifting aboveground-belowground mineral element flows in acid soil. This study highlights the importance of microbial keystone taxa for sustainable crop productivity in acid soil and provides deep insights into the relationships between soil microbial keystone taxa, crop mineral nutrition, and productivity.

Chinese Herbal Medicine Alleviates Myocardial Ischemia/Reperfusion Injury by Regulating Endoplasmic Reticulum Stress.

Myocardial ischemia/reperfusion injury is the main cause of increased mortality and disability in cardiovascular diseases. The injury involves many pathological processes, such as oxidative stress, calcium homeostasis imbalance, inflammation, and energy metabolism disorders, and these pathological stimuli can activate endoplasmic reticulum stress. In the early stage of ischemia, endoplasmic reticulum stress alleviates the injury as an adaptive survival response, but the long-term stress on endoplasmic reticulum amplifies oxidative stress, inflammation, and calcium overload to accelerate cell damage and apoptosis. Therefore, regulation of endoplasmic reticulum stress may be a mechanism to improve ischemia/reperfusion injury. Chinese herbal medicine has a long history of clinical application and unique advantages in the treatment of ischemic heart diseases. This review focuses on the effect of Chinese herbal medicine on myocardial ischemia/reperfusion injury from the perspective of regulation of endoplasmic reticulum stress.

[Expression Level and Target Gene Prediction of miR-181b in Patients with Chronic Lymphocytic Leukemia].

OBJECTIVE: To analyze the diagnostic value of multiple reverse transcription-polymerase chain reaction (RT-PCR) for detecting different fusion genes in children with primary acute lymphoblastic leukemia (ALL). METHODS: The clinical data of 80 children with ALL treated in the 2nd affiliated hospital of Xi'an Medical College from September 2012 to September 2017 were collected and retrospectively analyzed. Immunophenotype, chromosome karyotype and fusion gene were analyzed. RESULTS: Immunophenotyping showed that there were 2 cases of mixed expression of myeloid + B system, 2 cases with pre- B expression, 58 cases with former B expression, 11 cases with CD13 combined with pre- B expression, 4 cases with CD5 combined with pre- B expression, and 3 cases with CD2 combined with pre- B expression. The results of chromosome karyotype analysis showed that among 72 cases of karyotype analysts 5 cases could not be analyzed, 27 cases were determined to be normal karyotype, 11 cases with abnormal karyotype and 29 cases without mitotic phase. Six fusion genes were expressed in 30 cases (37.50%) of 80 ALL children, including MLL/AF9, CBF/MYH 11, BCR/ABL, TLS/ERG, MLL/ENL and TEL/AML1. Among the 3 cases with MLL/AF9 fusion gene expression [t(9;11)], 2 cases showed a poor response to early treatment, but achieved complete remission after intensive chemotherapy, and 1 case accepted bone marrow transplantation; in 1 case with CBF/MYH 11 fusion gene expression, treatment was abandoned by family members, and 4 cases with BCR/ABL fusion gene expression [t (9;22) (q34; q11)] were all showed poor response to early treatment, and achieved complete remission after intensive chemotherapy. All the fusion genes were positive during remission, including 2 cases of bone marrow transplantation; 1 case with TLS/ERG fusion gene expression [t (16;21)] displayed poor response to early treatment, and completely remitted after intensive chemotherapy; 2 cases with MLL/ENL fusion gene expression [t (11;19)] recurred during chemotherapy; 19 cases with TEL/AML1 fusion gene expression [t (12;21)] also achieved complete remission. 4 cases achieved a partial remission. CONCLUSION: Genotyping can make up for the insufficiency of MICM typing, and multiplex RT-PCR can be used to rapidly detect the fusion genes caused by chromosomal aberration in children with ALL.

Requirement of Rab21 in LPS-induced TLR4 signaling and pro-inflammatory responses in macrophages and monocytes.

Lipopolysaccharide (LPS) induces macrophage/monocyte activation and pro-inflammatory cytokines production by activating Toll-like receptor 4 (TLR-4) signaling. Rab GTPase 21 (Rab21) is a member of the Rab GTPase subfamily. In the present study, we show that LPS induced TLR4 and Rab21 association and endosomal translocation in murine bone marrow-derived macrophages (BMDMs) and primary human peripheral blood mononuclear cells (PBMCs). In BMDMs, shRNA-mediated stable knockdown of Rab21 inhibited LPS-induced expression and production of pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α). Conversely, forced overexpression of Rab21 by an adenovirus construct potentiated LPS-induced IL-1ß, IL-6 and TNF-α production in BMDMs. Further studies show that LPS-induced TLR4 endosomal traffic and downstream c-Jun and NFκB (nuclear factor-kappa B) activation were significantly inhibited by Rab21 shRNA, but intensified with Rab21 overexpression in BMDMs. Finally, in the primary human PBMCs, siRNA-induced knockdown of Rab21 significantly inhibited LPS-induced IL-1ß, IL-6 and TNF-α production. Taken together, we suggest that Rab21 regulates LPS-induced pro-inflammatory responses by promoting TLR4 endosomal traffic and downstream signaling activation.

GSK621 activates AMPK signaling to inhibit LPS-induced TNFα production.

LPS stimulation in macrophages/monocytes induces TNFα production. We here tested the potential effect of GSK621, a novel AMP-activated protein kinase (AMPK) activator, against the process. In RAW264.7 macrophages, murine bone marrow-derived macrophages (BMDMs), and chronic obstructive pulmonary disease (COPD) patients' monocytes, GSK621 significantly inhibited LPS-induced TNFα protein secretion and mRNA synthesis. Inhibition of AMPK, through AMPKα shRNA knockdown or dominant negative mutation (T172A), almost abolished GSK621's suppression on TNFα in RAW264.7 cells. Reversely, forced-expression of a constitutively-active AMPKα (T172D) mimicked GSK621 actions and reduced LPS-induced TNFα production. Molecularly, GSK621 suppressed LPS-induced reactive oxygen species (ROS) production and nuclear factor kappa B (NFκB) activation. In vivo, GSK621 oral administration inhibited LPS-induced TNFα production and endotoxin shock in mice. In summary, GSK621 activates AMPK signaling to inhibit LPS-induced TNFα production in macrophages/monocytes.

Quantized stabilization of wireless networked control systems with packet losses.

This paper considers stabilization of discrete-time linear systems, where wireless networks exist for transmitting the sensor and controller information. Based on Markov jump systems, we show that the coarsest quantizer that stabilizes the WNCS is logarithmic in the sense of mean square quadratic stability and the stabilization of this system can be transformed into the robust stabilization of an equivalent uncertain system. Moreover, a method of optimal quantizer/controller design in terms of linear matrix inequality is presented. Finally, a numerical example is provided to illustrate the effectiveness of the developed theoretical results.

[Distribution of Redox Zone at Different Water Layers in the Presence of Periphyton and the Responsible Microorganisms].

So far, many types of carriers (such as artificial mat, industrial soft carriers) have been widely used in removing pollutants, purifying water quality via the periphyton attached on the surface of these carriers. In the presence of periphyton, the distribution of redox zone at different water layers is directly or indirectly associated with the removal rate of pollutants. Therefore, it is more practically significant to study the distribution of redox zone at different water layers and the microbial diversity in the presence of periphyton. In this study, the pilot experiment was performed in a simulated water column bioreactor. Firstly, the eutrophic water collected from XuanWu Lake was added into the simulated water column bioreactor. The industrial soft carriers were then suspended into the water column in order to enhance the growth of periphyton. After periphyton gained a steady growth state, the oxidation reduction zones (redox zones) and the responsible microorganisms at different water layers were monitored. The results showed that five sequent redox zones (i. e. oxygen reduction, nitrate reduction, iron reduction, methanogenic and sulfate reduction zones, respectively) appeared in different water layers from top-down in the presence of periphyton and their responsible terminal electron acceptors were O2, NO3(-), Fe3+, CO2 and SO4(2-) respectively. The indicators of the different zones were DO, NO2(-), Fe(2+), HCO3(-) and sulfide, and the highest concentrations were 11.290 mg x L(-1), 4.950 mg x L(-1), 38.326 mg x L(-1), 120.000 mg x L(-1) and 12.180 mg x L(-1), respectively. The results of microbiological characteristics tested by Biolog EcoPlate technology revealed that there were significant differences in the composition, metabolic activity, carbon utilization of periphyton at different water layers, causing the difference in the distribution of redox zones at different water layers. These findings implies that study on the distribution of redox zones and microbiological characteristics in the presence of periphyton provides a better understanding that periphyton is capable of improving water quality at different layer, and also provides some theoretical basis for the development of technology for purifying water quality based on periphyton.

Stop and restart of granular clock in a vibrated compartmentalized bidisperse granular system.

This paper studies a bidisperse granular mixture consisting of two species of stainless steel spheres in a vertically vibrated compartmentalized container. The experiments show that with proper vibration acceleration, the granular clock stops when horizontal segregation of the large spheres residing in the far end from the barrier wall occurs. When the segregation is broken, the granular clock restarts. We present the phase diagrams of vibration acceleration versus container width and small particle number, which exhibits three different regions, namely, clustering state, stop-restart of the granular clock, and the granular clock. A generalized flux model is proposed to reproduce the phenomenon of stop and restart of the granular clock.

Effect of branchings on blood flow in the system of human coronary arteries.

In this work, we investigate the behavior of the pulsatile blood flow in the system of human coronary arteries. Blood is modeled as an incompressible non-Newtonian fluid. The transient phenomena of blood flow through the coronary system are simulated by solving the three dimensional unsteady state Navier-Stokes equations and continuity equation. Distributions of velocity, pressure and wall shear stresses are determined in the system under pulsatile conditions on the boundaries. Effect of branching vessel on the flow problem is investigated. The numerical results show that blood pressure in the system with branching vessels of coronary arteries is lower than the one in the system with no branch. The magnitude of wall shear stresses rises at the bifurcation.

Effects of formoterol-budesonide on airway remodeling in patients with moderate asthma.

AIM: To evaluate the effect of inhaled formoterol-budesonide on airway remodeling in adult patients with moderate asthma. METHODS: Thirty asthmatic patients and thirty control subjects were enrolled. Asthmatic subjects used inhaled Symbicort 4.5/160 µg twice daily for one year. The effect of formoterol-budesonide on airway remodeling was assessed with comparing high-resolution computer tomography (HRCT) images of asthmatic patients and controls, as well as expression levels of cytokines and growth factors, inflammatory cell count in induced sputum, and airway hyper-responsiveness. RESULTS: The differences in age and gender between the two groups were not significant. However, differences in FVC %pred, FEV(1) %pred, and PC(20) between the two groups were significant. After treatment with formoterol-budesonide, the asthma patients' symptoms were relieved, and their lung function was improved. The WT and WA% of HRCT images in patients with asthma was increased, whereas treatment with formoterol-budesonide caused these values to decrease. The expression of MMP-9, TIMP-1, and TGF-ß(1) in induced sputum samples increased in patients with asthma and decreased dramatically after treatment with formoterol-budesonide. The WT and WA% are correlated with the expression levels of cytokines and growth factors, inflammatory cell count in induced sputum, and airway hyper-responsiveness, while these same values are correlated negatively with FEV(1)/FVC and FEV(1)%. CONCLUSION: Formoterol-budesonide might interfere in chronic inflammation and airway remodeling in asthmatic patients. HRCT can be used to effectively evaluate airway remodeling in asthmatic patients.

[The clinical significance of noninvasive inflammatory markers in exhaled breath condensate and induced sputum in persistent asthmatic patients].

OBJECTIVE: To assess the clinical significance of three different noninvasive airway inflammatory indices in induced sputum and exhaled breath condensate (EBC) from persistent asthmatic patients. METHODS: Moderate and severe asthmatic patients were prescribed inhaled corticosteroids combined with long-acting beta(2) agonists for a month. The symptom scores and percentage of predicted value of forced expiratory volume in one second (FEV(1)) (FEV(1)%pred) were measured while the concentrations of H(2)O(2), NO(3)(-)/NO(2)(-), and cysteinyl-leukotriene E(4) (LTE(4)) in induced sputum and EBC were detected before and after therapy. RESULTS: A total of twenty-five subjects with moderate and severe asthma were enrolled. By combined therapy for one month the asthma symptoms relieved and FEV(1)%pred improved significantly (P < 0.01). The concentrations of H(2)O(2), NO(3)(-)/NO(2)(-) and LTE(4) in induced sputum and EBC declined significantly (P < 0.01) although the concentrations were still higher than those at normal baseline. More marked reduction of H(2)O(2) and NO(3)(-)/NO(2)(-) compared to LTE(4) was observed. It was revealed that the concentrations of H(2)O(2)and NO(3)(-)/NO(2)(-) but not of LTE(4) in EBC were negatively correlated with FEV(1)%pred (P < 0.01) and positively with symptom scores. Such correlations were also found in H(2)O(2) in induced sputum with FEV(1)%pred and symptom scores as well as NO(3)(-)/NO(2)(-) in induced sputum with FEV(1)%pred. The improvement of FEV(1)%pred after treatment was positively correlated with the reduction of H(2)O(2) and NO(3)(-)/NO(2)(-) both in induced sputum and EBC. Correlation analysis also demonstrated three inflammatory indices were equivalent in induced sputum and EBC (correlation coefficient of H(2)O(2), NO(3)(-)/NO(2)(-) and LTE(4), 0.759, 0.826 and 0.653, respectively. P < 0.01). CONCLUSIONS: (1) Combined therapy with inhaled corticosteroid plus long-acting beta(2) agonist significantly improves the clinical symptoms and lung function of patients with moderate and severe asthma companies with marked suppression of airway inflammation. (2) Both of EBC and induced sputum sampling are valuable noninvasive procedures for detecting asthma airway inflammation, however, EBC technique is superior in safety and reproducibility. (3) H(2)O(2) and NO(3)(-)/NO(2)(-) seem to be more sensitive indices in diagnosis and monitoring asthma compared to LTE(4).

Dynamical hysteresis phenomena in complex network traffic.

In this Brief Report, the dynamical hysteresis is investigated in constant-density traffic system of scale-free, small-world, and lattice networks. With the local-searching strategy, hysteresis persists for scale-free networks, while it disappears for small-world networks and lattice grids when the handling ability of nodes is higher than a certain threshold. With the shortest-path-routing strategy, hysteresis persists for all three networks investigated. When using shortest-path strategy, the system is easy to congest and difficult to recover to free-flow state.

[The relevance of leukotriene C(4) synthase gene A (-444) C polymorphism to clinical responsiveness to montelukast in patients with asthma].

OBJECTIVE: To investigate the frequency of leukotriene C(4) synthase gene A (LTC(4)S A) -444 C polymorphism in asthmatics of Chinese Han nationality in Southwest China and to evaluate its relevance to clinical responsiveness to leukotriene receptor antagonist. METHODS: A hundred and fifty asthmatics and 146 healthy blood donors were recruited. The genotype distribution of A/C polymorphism of LTC(4)S A(-444)C gene was analyzed by RELP (restriction fragment length polymorphism). Eighty asthmatics were randomly recruited for a 4 week prospective trial of montelukast and their clinical response to montelukast was evaluated by ACQ and pulmonary function. Urine LTE(4) was detected by ELISA (enzyme linked immunosorbent assay) in asthma patients before and after treatment. RESULTS: In the 150 asthma patients, the frequencies of A and C alleles at -444 locus of LTC(4)S gene were 83.7% and 16.3%, respectively, and the genotype frequencies of AA and AC/CC were 70.7% and 29.3%, respectively. In the 146 healthy blood donors, the frequencies of A and C alleles at -444 locus of LTC(4)S gene were 87.0% and 13.0%, respectively, and the genotype frequencies of AA and AC/CC were 76.7% and 23.3%, respectively. There was no significant difference in LTC(4)S A(-444)C polymorphism between the asthmatics and the healthy controls (chi(2) = 1.393, 1.301, P = 0.238, 0.25 4, P > 0.05). The asthmatics with the C(-444) allele were younger than the asthmatics with AA with earlier onset age and longer duration of disease compared to those with AA (both P < 0.05). However, there were no significant differences between the two groups in clinical and lung function parameters. Four-week montelukast therapeutic trial demonstrated that asthmatic patients with AC/CC genotype had better response than those with AA genotype and this difference was related to urine LTE(4) level (F = 12.01, P = 0.011). CONCLUSION: In a Southwest Chinese Han population LTC(4)S A(-444)C polymorphism might be a determinant factor in the clinical response of asthma to leukotriene receptor antagonists.

Spatial three-player prisoners' dilemma.

This paper extends traditional two-player prisoners' dilemma (PD) to three-player PD. We have studied spatial patterns of cooperation behaviors, growth patterns of cooperator clusters and defector clusters, and cooperation frequency of the players. It is found while three-player PD exhibits many properties similar to two-player PD, some new features arise. Specifically, (i) a new region appears, in which neither a 3x3 cooperator cluster nor a 3x3 defector cluster could grow; (ii) more growth patterns of cooperator clusters and defector clusters are identified; (iii) multiple cooperation frequencies exist in the region that exhibits dynamic chaos. Some theoretical analysis of these features is presented.

Weak and strong coupling in a two-lane asymmetric exclusion process.

This paper studies a two-lane totally asymmetric simple exclusion process, in which particles could jump between the two lanes with asymmetric rates. In the weak coupling situation, the rates are inversely proportional to system size L . The appearance of localized shock in one lane and the discontinuous phase transition as revealed by Juhász [Phys. Rev. E 76, 021117 (2007)] are also reproduced. The density profiles and phase diagrams are constructed in the hydrodynamic limit, by numerically solving the steady state equations. The phase diagram in our model exhibits asymmetry, which is different from the symmetric one in Juhász's model. We have studied the phase boundary and discontinuous line analytically. The analytical results are in good agreement with that obtained from numerical integration. We also study the strong coupling situation, in which the lane changing rates are independent of L . Results completely different from that arising from weak coupling are presented. Furthermore, features different from that of the model presented by Pronina and Kolomeisky [Physica A 372, 12 (2006)] are revealed.

Budesonide/formoterol decreases expression of vascular endothelial growth factor (VEGF) and VEGF receptor 1 within airway remodelling in asthma.

INTRODUCTION: Angiogenesis and microvascular remodelling may play a vital role in the chronic inflammatory process within asthma. One of the most important factors involved in angiogenesis is vascular endothelial growth factor (VEGF). In this study we hypothesised that an increased expression of VEGF may be involved in airway remodelling in asthma patients. To this end, we compared the histology and expression levels of VEGF and one of its receptors (VEGFR1) in bronchial tissues of patients with asthma compared with control patients. We also investigated the effect of treatment with budesonide/formoterol (Symbicort; AstraZeneca, Lund, Sweden) in the relationship between VEGF and airway remodelling. METHODS: Bronchial tissues were obtained from patients attending the West China Hospital from April to November 2006. Thirteen patients were diagnosed with moderate asthma and 10 others were treated as control. Histological and immunohistochemical comparisons between asthmatic and control patients were made at baseline, and (for asthmatic subjects) following 6 months of treatment with budesonide/formoterol. RESULTS: Compared with control patients, asthmatic patients had significantly decreased respiratory parameters, including forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV(1)) (% predictive). Furthermore, patients with asthma had submucosal gland hyperplasia, increased smooth muscle mass, increased subepithelial fibrosis and neovascularisation. Asthmatic patients also exhibited increased expression of VEGF and VEGFR1 within epithelial cells. The increased expression of VEGF and its receptor correlated well with airway remodelling, airflow obstruction and airway hyper-responsiveness. After treatment with budesonide/formoterol for 6 months, the expression of VEGF and VEGFR1 was decreased, with correlatory decreased airway remodelling in patients with asthma. CONCLUSION: The increased expression of VEGF and VEGFR(1) in asthmatic patients is accompanied by an increased number and size of blood vessels in asthmatic airways, as well as airway remodelling. Budesonide/formoterol therapy for 6 months can decrease the expression of VEGF and VEGFR(1) alongside airway remodelling in asthma. The inhibition of VEGF and its receptor may be a good therapeutic strategy for asthma.

Phase transition and hysteresis in scale-free network traffic.

We model information traffic on scale-free networks by introducing the node queue length L proportional to the node degree and its delivering ability C proportional to L . The simulation gives the overall capacity of the traffic system, which is quantified by a phase transition from free flow to congestion. It is found that the maximal capacity of the system results from the case of the local routing coefficient phi slightly larger than zero, and we provide an analysis for the optimal value of phi. In addition, we report for the first time the fundamental diagram of flow against density, in which hysteresis is found, and thus we can classify the traffic flow with four states: free flow, saturated flow, bistable, and jammed.

[Chemical characteristics of nitrogen and phosphorus in the sediments of the typical bays in Dianchi Lake and calculation of their dredging layers].

The sediments of Haidong bay and Macun bay in Dianchi Lakes' experimental area were studied. The sediment column was cut in every 3cm, and the following items are tested, such as total phosphorus, phosphorus species, which include labile phosphate, Fe,Al-P, Ca-P and residual-P, total nitrogen, nitrate nitrogen, nitrite nitrogen, ammonium nitrogen. The results showed that the loads of nitrogen and phosphorus of these two bays increased quickly in recent years. The Fe, Al-P was the largest component in all the P-forms and the content of ammonium nitrogen in these two bays less than that of other lakes. The layer of 9 to 12 centimeters of the two bays was polluted less than the rests. It indicated that these years more and more wastewater was inflow in these two bays. At the same time, the distribution of each testing items showed another low value between 24 to 39 centimeters. So considering feasibility and economic restriction, we can set the 24 - 39 centimeters depth as a dredging layer.

[Method of algae-bacterium biofilm to improve the water quality in eutrophic waters].

The quality of eutrophic waters was improved by the algae-bacterium biofilm, which covered over the artificial aquatic mat made from a kind of mend macromolecule material. Two series of experiments show that using the artificial aquatic mat technique, algae bloom was inhibited markedly. At the eleventh day, the transparency was increased from 6 cm to 62 cm; and the concentrations of COD(Mn), TP, TN and NH4(+) -N were decreased to 92.89%, 49.25% , 94.97% and 70.15% respectively. The DO concentration also kept in certain satisfied level for using the algae-bacterium biofilm method. The suitable and economical density was about 8 - 16 bunchs/m(2) when the ratio of the artificial aquatic mat length to water depth was 0.7.