Mine water cooperative optimal scheduling based on improved genetic algorithm.

This article addresses the issues of unreasonable water scheduling and high costs in coal mine shafts, proposing a hierarchical optimization scheduling strategy. Taking the water quality and quantity of a certain mining area in Inner Mongolia as the research object, it designs the objective function with the highest reuse efficiency and the lowest reuse cost of mine water resources, and establishes the constraint conditions of water quality and quantity for each water-using unit. In response to the problem that traditional genetic algorithms are prone to local optima, an adaptive autobiographical operator is proposed and improved based on Metropolis principle of simulated annealing algorithm. The improved algorithm is applied to the calculation of the scheduling model, and the results show that the recovery cost in the heating season is reduced by 66779.36 CNY/month, a decrease of 10.34%; the recovery cost in the non-heating season is reduced by 61469.28 CNY/month, a decrease of 9.91%. At the same time, the heating season and the non-heating season have reduced by 136.99 h/month and 154.52 h/month respectively, significantly reducing the recovery cost and time.

Research on the data validity of a coal mine solid backfill working face sensing system based on an improved transformer.

Solid backfilling in coal mining refers to filling the goaf with solid materials to form a support structure, ensuring safety in the ground and upper mining areas. This mining method maximizes coal production and addresses environmental requirements. However, in traditional backfill mining, challenges exist, such as limited perception variables, independent sensing devices, insufficient sensing data, and data isolation. These issues hinder the real-time monitoring of backfilling operations and limit intelligent process development. This paper proposes a perception network framework specifically designed for key data in solid backfilling operations to address these challenges. Specifically, it analyses critical perception objects in the backfilling process and proposes a perception network and functional framework for the coal mine backfilling Internet of Things (IoT). These frameworks facilitate rapidly concentrating key perception data into a unified data centre. Subsequently, the paper investigates the assurance of data validity in the perception system of the solid backfilling operation within this framework. Specifically, it considers potential data anomalies that may arise from the rapid data concentration in the perception network. To mitigate this issue, a transformer-based anomaly detection model is proposed, which filters out data that does not reflect the true state of perception objects in solid backfilling operations. Finally, experimental design and validation are conducted. The experimental results demonstrate that the proposed anomaly detection model achieves an accuracy of 90%, indicating its effective detection capability. Moreover, the model exhibits good generalization ability, making it suitable for monitoring data validity in scenarios involving increased perception objects in solid backfilling perception systems.

[Research Progress on the Interaction Between Microorganisms and Macrophages and Their Role in the Mediation of the Onset and Development of Oral Cancer].

Oral squamous cell carcinoma is the sixth most common malignant tumor in the world, and the clinical treatment effect is not satisfactory. Because of the special nature of its location, oral cancer is inextricably linked with a wide variety of microorganisms, and its pathogenesis and development are also extremely susceptible to microbial regulation. In addition, the mediating role of the immune system is also indispensable to the course of tumor pathogenesis and development, especially tumor-associated macrophages, which amplify the regulatory role of microorganisms, and in turn regulate the microbial population components--two complementary effects that jointly exacerbate oral cancer. Herein, we summarized the existing research on the relationship between microorganisms and macrophages, as well as the regulatory role of microorganisms and macrophages in the pathogenesis and development of oral cancer. We also discussed the current status of and gaps in research on the relationship between microorganisms and macrophages and oral cancer. Both microorganisms and macrophages are considered promising indicators for prognosis, showing potentials to be used as new therapeutic targets. Despite some research interest in the role of microorganisms and macrophages in oral cancer, very few studies have linked them to oral precancerous lesions, and the mutual regulatory relationship between microorganisms and macrophages remains unclear. Therefore, in-depth exploration of the relationship network of microorganisms, macrophages and oral cancer is expected to provide more possibilities for the early diagnosis and treatment of tumors.

Research on Multi-Level Scheduling of Mine Water Reuse Based on Improved Whale Optimization Algorithm.

Aiming at the problem of the inefficiency of coal mine water reuse, a multi-level scheduling method for mine water reuse based on an improved whale optimization algorithm is proposed. Firstly, the optimization objects of mine water reuse time and reuse cost are used to establish the optimal scheduling model of mine water. Secondly, in order to overcome the defect that the whale optimization algorithm (WOA) is prone to local convergence, the opposition-based learning strategy is introduced to speed up the convergence speed, the Levy flight strategy is used to enhance the ability of the algorithm to jump out of the local optimization, the nonlinear convergence factor is used to balance the global and local search ability, and the adaptive inertia weight is used to improve the optimization accuracy of the algorithm. Finally, the improved whale optimization algorithm (IWOA) is applied to the mine water optimization scheduling model with multiple objects and constraints. The results show that the reuse efficiency of the multi-level scheduling method of mine water reuse is increased by 30.2% and 31.9%, respectively, in the heating and nonheating seasons, which can significantly improve the reuse efficiency of mine water and realize the efficient utilization of mine water reuse deployment. At the same time, experiments show that the improved whale optimization algorithm has higher convergence accuracy and speed, which proves the feasibility and superiority of its improvement strategies.

Optimal Reuse Design Scheduling of Mine Water Based on Improved Whale Algorithm.

The optimal scheduling of mine water is a multi-objective, multi-constraint, nonlinear, multi-stage combination of optimization problems, in view of the traditional solution methods with the increase in decision-making variable dimensions facing a large amount of computation, "dimensional disaster" and other problems, the introduction of a new intelligent simulation algorithm-the Whale Optimization Algorithm to solve the optimal scheduling problem of mine water. Aiming at the problem that the Whale Optimization Algorithm itself is prone to local optimization and slow convergence, it has been improved by improving its own parameters and introducing the inertia weight of the particle swarm and has achieved more obvious results. According to the actual situation of Nalinhe No. 2 Mine, the mathematical model of multi-target optimization of mine water is established based on the function of reuse time and reuse cost of mine water as the target function, and the balance of supply and demand of mine water, the water quality requirements of water use points at all levels, the water quantity requirements of reservoirs and the priority of water supply as the constraints. The improved Whale Optimization Algorithm was used to search optimal solution, and the results showed that the adaptability value of the improved Whale Optimization Algorithm was significantly improved compared with before, of which 8.65% and 7.69% were increased in the heating season and non-heating season, and the rate of cost reduction was 46.80% and 36.92%, and the iteration efficiency was also significantly improved, which improved the decision-making efficiency of optimal scheduling and became more suitable for the actual scheduling needs of Nalinhe No. 2 mine.

Economic Optimal Allocation of Mine Water Based on Two-Stage Adaptive Genetic Algorithm and Particle Swarm Optimization.

The waste mine water is produced in the process of coal mining, which is the main cause of mine flood and environmental pollution. Therefore, economic treatment and efficient reuse of mine water is one of the main research directions in the mining area at present. It is an urgent problem to use an intelligent algorithm to realize optimal allocation and economic reuse of mine water. In order to solve this problem, this paper first designs a reuse mathematical model according to the mine water treatment system, which includes the mine water reuse rate, the reuse cost at different stages and the operational efficiency of the whole mine water treatment system. Then, a hybrid optimization algorithm, GAPSO, was proposed by combining genetic algorithm (GA) and particle swarm optimization (PSO), and adaptive improvement (TSA-GAPSO) was carried out for the two optimization stages. Finally, simulation analysis and actual data detection of the mine water reuse model are carried out by using four algorithms, respectively. The results show that the hybrid improved algorithm has better convergence speed and precision in solving the mine water scheduling problem. TSA-GAPSO algorithm has the best effect and is superior to the other three algorithms. The cost of mine water reuse is reduced by 9.09%, and the treatment efficiency of the whole system is improved by 5.81%, which proves the practicability and superiority of the algorithm.

Incidence of Voice Disorders among Private School Teachers in Taiwan: A Nationwide Longitudinal Study.

Background: Teachers are more likely to use a loud voice at work than the general working population, but few longitudinal studies have been conducted on their risk of voice disorders. The occurrence of voice disorders in private school teachers was assessed by using the Longitudinal Health Insurance Database 2000 of Taiwan, which contains information on a random sample of 1 million beneficiaries of National Health Insurance. Methods: This study included private school teachers who were under 35 years old and newly employed between 2000 and 2010, and used workers with other occupations as the comparison cohort. Patients with voice disorders were identified using diagnostic codes on insurance claims. Cox proportional hazards regressions were applied to obtain relative risk estimates. Results: After adjusting for age, sex, income, and comorbidities of sinusitis and laryngitis, private school teachers had a higher risk of developing voice disorders (hazard ratio [HR] = 1.58; 95% confidence intervals: 1.43-1.75). In addition, the finding that elementary and high-school teachers had a higher risk than college teachers (HR: 2.56 vs. 1.44) and the pattern of increases in cumulative incidence over time supported a dose-response relationship between teaching and voice disorders. Conclusions: Private school teachers had higher risks of voice disorders. The results support the causality between occupation and voice disorders in teachers.

Multi-Objective Optimization of a Mine Water Reuse System Based on Improved Particle Swarm Optimization.

This paper proposes a general hierarchical dispatching strategy of mine water, with the aim of addressing the problems of low reuse rate of coal mine water, and insufficient data analysis. First of all, water quality and quantity data of the Narim River No. 2 mine were used as the research object; the maximum reuse rate of mine water and the system operation rate comprised the objective function; and mine water quality information, mine water standard, and mine water treatment speed were the constraints. A multi-objective optimization scheduling mathematical model of water supply system was established. Then, to address the problems of premature convergence and ease of falling into a local optimum in the iterative process of particle swarm optimization, the basic particle swarm optimization was improved. Using detailed simulation research, the superiority of the improved algorithm was verified. Eventually, the mine water grading dispatching strategy proposed in this paper is compared with the traditional dispatching method. The results show that the hierarchical dispatching system can significantly improve the mine water reuse rate and system operating efficiency.

[Internal quality control products for computer-assisted sperm analysis: Research and application].

OBJECTIVE: To investigate the application of the self-made semen quality control (QC) product in internal QC of computer-assisted sperm analysis (CASA). METHODS: CASA was calibrated with high- and low-concentration commercially available semen QC product and meanwhile 15 samples of self-made mixed semen QC product were placed in 75 cryotubes containing liquid nitrogen, followed by CASA of the concentration, motility, curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), linearity (LIN), wobble (WOB) and straightness (STR) of the sperm using standard procedures and 50 days of continuous monitoring. The Makler counting plate was used to measure the concentration and motility of the self-made sperm. RESULTS: The coefficients of variation (CV) of the commercially available semen QC product at high and low concentrations were 6.18% and 7.85%, respectively. CASA showed that the concentration of the self-made QC product was (25.97 ± 1.41) ×106/ml, with a CV of 5.42%, and the sperm motility, VCL, VSL, VAP, LIN, WOB and STR were (22.15 ± 1.75)% (CV = 7.9%), (59.18 ± 2.05) µm/s (CV = 3.46%), (26.79 ± 1.2) µm/s (CV = 4.48%), (34.98 ± 1.4) µm/s (CV = 4.01%), 46.81 ± 1.55 (CV = 3.3%), 60.52 ± 1.3 (CV = 2.15%) and 76.46 ± 1.98 (CV = 2.59%), respectively. The concentration and motility of the self-made sperm detected with the Makler counting plate were (34.39 ± 2.37) ×106/ml (CV = 6.89%) and (38.04 ± 1.69)% (CV = 4.44%), respectively. Levey-Jennings QC charts were plotted for the indicators using the means and standard deviation. CONCLUSIONS: The self-made internal QC product by liquid nitrogen cryopreservation is feasible and effective for monitoring the accuracy and precision of CASA-derived sperm concentration and motion parameters, and it has a smaller CV than the commercially available QC product in measuring sperm concentration.

Immersive virtual reality as analgesia for women during hysterosalpingography: study protocol for a randomized controlled trial.

BACKGROUND: Hysterosalpingography (HSG) is an accepted radiologic diagnostic modality for initial infertility workup, and is generally considered uncomfortable and painful. However, the management of pain related to HSG remains inefficient. As an emerging nonpharmacologic and noninvasive pain control strategy, virtual reality (VR) distraction has been successfully used in areas such as burns, blunt force trauma, hospital-based needle procedures, dental/periodontal procedures, and urological endoscopy patients. This study aims to evaluate the analgesic effect of VR during HSG. METHODS/DESIGN: A single-center, parallel-group, randomized controlled trial will be carried out in the Radiology Department of Yinchuan Women and Children Healthcare Hospital, Yinchuan. A total of 200 participants who are scheduled for HSG will be enrolled in this study. The participants will be randomized (1:1) into two groups: a VR group and a blank control group. The VR group will receive routine care plus immersive VR intervention and the blank control group will receive routine care. Outcomes will be monitored at baseline, immediately after HSG and 15 min after HSG for each group. The primary outcome is the worst pain score during HSG by a visual analog scale (VAS). The secondary outcomes include: affective pain, cognitive pain, and anxiety during the HSG procedure; worst pain within 15 min after HSG; patient satisfaction and acceptance with pain management; physiological parameters; adverse effects; HSG results; and immersion perception score of the VR system (for the VR condition only). DISCUSSION: This study will focus on exploring a simply operated, noninvasive and low-cost analgesia during the HSG procedure. The results of this trial will provide data on the feasibility and safety of VR distraction therapy during HSG. TRIAL REGISTRATION: Chinese Clinical Trial Register, ChiCTR1900021342. Registered on 16 February 2019.

Protective Effects of 18ß-Glycyrrhetinic Acid on Monocrotaline-Induced Pulmonary Arterial Hypertension in Rats.

Pulmonary arterial hypertension (PAH) is a destructive and rare disorder characterized by a progressive increase in pulmonary artery pressure and vasoconstriction, ultimately leading to right ventricular failure and death. 18ß-Glycyrrhetinic acid (18ß-GA) is an active ingredient in the commonly used Chinese herbal medicine radix glycyrrhizae, and it possesses antioxidant, anti-inflammatory, anti-tumor, and other pharmacological properties. This study aimed to determine whether 18ß-GA has protective effects against monocrotaline (MCT)-induced PAH and whether it is associated with oxidative stress. The PAH of rats was induced by MCT (60 mg/kg) and oral administration of 18ß-GA (100, 50, or 25 mg/kg/day), sildenafil (30 mg/kg), or saline for 21 consecutive days. The development of PAH was evaluated by hemodynamic parameters and right ventricular hypertrophy index. Hematoxylin and eosin staining, Masson trichrome staining, and electron microscopy were used to determine the degree of vascular remodeling and proliferation in lung tissue. Moreover, the antioxidant capacity and malondialdehyde levels in the lungs were measured according to the instructions provided by the test kits, and the expression levels of nicotinamide adenine dinucleotide phosphate oxidase-2 (Nox2) and Nox4 were detected through Western blot analysis. Results of our study indicated that 18ß-GA treatment significantly improved the hemodynamic and pathomorphological data of the rats, reduced the changes in oxidative stress biomarkers, and inhibited Nox2 and Nox4 expression. Our research indicated that 18ß-GA has a protective effect against MCT-induced PAH by inhibiting oxidative stress in rats.

Industrial potential of carotenoid pigments from microalgae: Current trends and future prospects.

Microalgae are rich source of various bioactive molecules such as carotenoids, lipids, fatty acids, hydrocarbons, proteins, carbohydrates, amino acids, etc. and in recent Years carotenoids from algae gained commercial recognition in the global market for food and cosmeceutical applications. However, the production of carotenoids from algae is not yet fully cost effective to compete with synthetic ones. In this context the present review examines the technologies/methods in relation to mass production of algae, cell harvesting for extraction of carotenoids, optimizing extraction methods etc. Research studies from different microalgal species such as Spirulina platensis, Haematococcus pluvialis, Dunaliella salina, Chlorella sps., Nannochloropsis sps., Scenedesmus sps., Chlorococcum sps., Botryococcus braunii and Diatoms in relation to carotenoid content, chemical structure, extraction and processing of carotenoids are discussed. Further these carotenoid pigments, are useful in various health applications and their use in food, feed, nutraceutical, pharmaceutical and cosmeceutical industries was briefly touched upon. The commercial value of algal carotenoids has also been discussed in this review. Possible recommendations for future research studies are proposed.

[Retinal transcriptome profile in mice following dexamethasone treatment for endotoxin-induced uveitis].

OBJECTIVE: To investigate the changes in retinal transcriptome profile of mice with endotoxin-induced uveitis (EIU)following dexamethasone (DEX) treatment and explore the mechanisms underlying the therapeutic effect of DEX. METHODS: EIU was induced in BALB/c mice by intravitreal injection of 125 ng lipopolysaccharide (LPS), followed by topical applicationof DEX (0.1%) eye drops every 4 h for 24 h. The anterior chamber inflammation was examined with a slit lamp and the clinicalscores were assessed. The morphological changes in the eyes were assessed at 24 h after LPS injection. The retinas wereharvested for analysis of transcriptome profile using the next-generation sequencing (NGS)-based RNA sequencing (RNA-seq), and the expressions of the inflammatory cytokines and the differentially expressed genes (DEGs) were verified using real-timePCR. RESULTS: DEX alleviated the inflammatory response and reduced the mRNA expressions of IL-6, TNF- a, MCP-1 andICAM-1 at 24 h after LPS injection. A total of 52 DEGs were identified by RNA-seq. Within these DEGs, 37 genes were upregulated and 15 genes were down-regulated in LPS group as compared with DEX+LPS group. No significantly enriched GeneOntology (GO) terms was noted. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed 6up-regulated and 2 down-regulated KEGG pathways. RIG-I-like receptor signaling pathway and several immune- andinflammation-related genes including Ifit1, H2-T24, Mx2 and Eif2ak2 were significantly down regulated by DEX. Verificationwith RT-PCR yielded results consistent with these findings. CONCLUSIONS: DEX alleviates LPS-induced inflammatory response inthe retina of mice, and such protective effect is probably mediated by RIG-I like receptor signal pathway and the immune-andinflammation-related genes.

Respiratory symptoms among search and rescue workers who responded to the 2016 Taiwan earthquake.

OBJECTIVES: High respiratory hazards among search and rescue workers (SRWs) emerged after the World Trade Center attacks on 11 September 2001. There have been limited studies on respiratory symptoms among earthquake SRWs. We investigated the respiratory symptoms and the use of respiratory protective equipment among the SRWs who responded to the 2016 Taiwan earthquake. METHODS: On 6 February 2016, a 6.4-magnitude earthquake struck southern Taiwan and caused 513 injuries and 117 deaths. During the 9-day field operation, 519 firefighters affiliated with the Tainan City Government Fire Bureau participated in the search and rescue response. A standardised, self-completed questionnaire was used to collect data on demographics, dust exposures, personal protective measures and health outcomes 3 weeks after the earthquake. Descriptive and multivariate analyses adjusting for demographics and exposure variables were performed for new or worsened outcomes. RESULTS: Of the 519 SRWs, 414 (80%) responded to the questionnaire. Of these SRWs, 153 (37%) reported new or worsened respiratory symptoms, with cough (23%) as the leading symptom, followed by rhinorrhoea or nasal congestion (22%) and chest tightness (6%). More than 90% of the symptoms persisted to the third week after the earthquake. The prevalence of new or worsened respiratory symptoms was significantly higher among SRWs with a higher level of exposure to dust. Prior training in response to respiratory pollutants was only 5%. CONCLUSIONS: There were significant respiratory hazards among earthquake SRWs. The persistent symptoms and low coverage of training warrant further regular examination and occupational health programmes.

[Research progress on the relationship between oral microbes and digestive system diseases].

The human microbiome project promoted further understanding on human oral microbes. Besides oral diseases such as dental caries, periodontal disease, and oral cancer, oral microbes are closely associated with systematic diseases. They have a close connection with digestive system diseases and even contribute to the origination and progression of colorectal cancer. By reviewing recent studies involving oral microbe-related digestive systemic diseases, we aim to propose the considerable role of oral microbes in relation to digestive systemic diseases and the way of oral microbes to multiple organs of digestive system.

Do Open Reduction and Internal Fixation With Articular Disc Anatomical Reduction and Rigid Anchorage Manifest a Promising Prospect in the Treatment of Intracapsular Fractures?

PURPOSE: In response to the increased attention to soft tissue reduction in the treatment of intracapsular condylar fractures (ICFs), a modified open reduction technique is proposed and its functional and radiographic outcomes were evaluated in this study. PATIENTS AND METHODS: This is a retrospective case series study of patients with all ICF types that were treated with open reduction and internal fixation (ORIF) with articular disc anatomic reduction and rigid anchorage. Inclusion and exclusion criteria were strictly applied. Preoperative and postoperative clinical examinations of malocclusion, maximum incisor opening (MIO), laterotrusion, and temporomandibular disorder symptoms were recorded and analyzed. Computed tomography (CT) and magnetic resonance imaging (MRI) were used to assess articular position and condylar morphology and position. RESULTS: Thirty-four patients with ICFs (47 sides) were treated with the modified ORIF technique. At 6 months of follow-up, no malocclusion was found and the MIO considerably expanded to 3.56 ± 0.13 cm. Only 4 patients (12%) had temporomandibular joint discomfort with mouth opening. Interestingly, for unilateral type B ICFs, the laterotrusion distance to the ORIF sides was notably longer than to the non-ORIF sides. Postoperative CT and MRI showed that all fragments were properly reduced and the condyles were in the normal position. Postoperative anterior disc displacement occurred in 4 sides and condylar morphologic abnormalities (slight surface roughening and articular cartilage absorption) occurred in 3 sides (6.4%). CONCLUSIONS: This modified ORIF technique, which achieved good outcomes after treatment of all ICF types, shows promise for the treatment of ICFs.

Mandibular Coronoidectomy Could Significantly Accelerate the Healing Process of Infratemporal Fossa Abscess.

PURPOSE: Management of an infratemporal fossa abscess (IFA), which is a specific form of severe and advanced deep fascial space infection (DFI), is based mainly on traditional methods. The purpose of this study was to investigate the role of mandibular coronoidectomy in accelerating IFA healing. PATIENTS AND METHODS: This research is a single-center retrospective study composed of 23 patients with IFA. The predictor variables were gender, age, diabetes, severity score, and mandibular coronoidectomy. The outcome variables included hospitalization time (HT) and irrigating time (IT). A comparison of treatment outcomes between the improved and traditional surgical interventions for IFA was performed. RESULTS: Compared with patients who did not receive mandibular coronoidectomy (NC group; HT, 17.54 ± 1.80 days; IT, 38.54 ± 3.73 days), patients who underwent mandibular coronoidectomy (AC group) had significantly decreased HT (7.20 ± 1.19 days) and IT (15.10 ± 1.27 days; P < .01). In addition, 4 patients (31%) in the NC group received reoperation for osteomyelitis, whereas no osteomyelitis and DFI recurrence occurred in the AC group. CONCLUSIONS: Mandibular coronoidectomy with extra intraoral drainage could considerably accelerate the healing process of IFAs and obviously decrease the reoperation rate for osteomyelitis.

Nuclear Multidrug Resistance-Related Protein 1 Is Highly Associated with Better Prognosis of Human Mucoepidermoid Carcinoma through the Suppression of Cell Proliferation, Migration and Invasion.

OBJECTIVES: Multidrug resistance-related protein 1 (MRP1) overexpression is a well acknowledged predictor of poor response to chemotherapy, but MRP1 also correlated to better prognosis in some reports, especially for patients not pretreated with chemotherapy. In our previous study, we found nuclear translocation of MRP1 in mucoepidermoid carcinoma (MEC) for the first time. The purpose of this study was to further investigate the function of nuclear MRP1 in MEC. MATERIALS AND METHODS: Human MEC tissue samples of 125 patients were selected and stained using immunohistochemistry. The expression level of total MRP1/nuclear MRP1 of each sample was evaluated by expression index (EI) which was scored using both qualitative and quantitative analysis. The correlations between the clinicopathologic parameters and the EI of nuclear MRP1 were analyzed using Spearman's rank correlation analysis, respectively. The effects of RNAi-mediated downregulation of nuclear MRP1 on MEC cells were assessed using flow cytometric analysis, MTT assay, plate colony formation assay, transwell invasion assay and monolayer wound healing assay. RESULTS: In this study, we found the EI of nuclear MRP1 was negatively correlated to the pathologic grading (r = -0.498, P<0.01)/clinical staging (r = -0.41, P<0.01)/tumor stage (r = -0.28, P = 0.02)/nodal stage (r = -0.29, P<0.01) of MEC patients. The RNAi-mediated downregulation of nuclear MRP1 further proved that the downregulation of nuclear MRP1 could increase the cell replication, growth speed, colony formation efficiency, migration and invasion ability of MEC cells. CONCLUSION: Our results suggested that nuclear MRP1 is highly associated with better prognosis of human mucoepidermoid carcinoma and further study of its function mechanism would provide clues in developing new treatment modalities of MEC.

[Microbial Community Structure on the Root Surface of Patients with Periodontitis.]

OBJECTIVES: To study the microbial community structure on the root surface of patients with periodontitis. METHODS: Bacterial plaque and tissues from the root neck (RN group),root middle (RM group) and root tine (RT group) of six teeth with mobility 3 in one patient with periodontitis were sampled.The V3V4 region of 16S rRNA was sequenced on the Illumina MiSeq platform.The microbial community structure was analyzed by Mothur,Qiime and SPSS software. RESULTS: The principal component analysis (PCoA) results indicated that the RM samples had a similar microbial community structure as that of the RT samples,which was significant different from that of the RN samples.Thirteen phyla were detected in the three groups of samples,which included 7 dominant phyla.29 dominant genera were detected in 184 genera.The abundance of Bacteroidetes_[G-6] and Peptostre ptococcaceae_[XI][G-4] had a positive correlation with the depth of the collection site of samples (P<0.05),while the abundance of Prevotella,Selenomonas,Corynebacterium and Olsenella had a negative correlation with the depth of the collection site of samples (P<0.05). CONCLUSIONS: There is region-specificity of microbial community structure on the root surface of patients with periodontitis.

Assessment of pollution and identification of sources of heavy metals in the sediments of Changshou Lake in a branch of the Three Gorges Reservoir.

To assess the heavy metal pollution in Changshou Lake, sediments were collected from nine sites at three periods (dry, normal, and wet) in 2013. The Hg, As, Cr, Cd, Pb, Cu, and Zn levels were then determined. The index of geoaccumulation (I geo) and the sediment pollution index (SPI) were applied to the sediment assessment, and Pearson's correlation analysis and factor analysis (FA) were performed to identify common pollution sources in the basin. The results showed that heavy metals presented significant spatial variations with Cr, Cd, Pb, Cu, Zn, Hg, and As concentrations of 29.66~42.58, 0.62~0.91, 24.91~37.96, 21.18~74.91, 41.65~86.86, 0.079~0.152, and 20.17~36.88 mg kg(-1), respectively, and no obvious variations were found among the different periods. The average contents of the metals followed the order Zn > Cu > Cr > Pb > As > Cd > Hg, which showed a high pollution in the sediments collected from open water and at the river mouth. The assessment results indicated that toxic heavy metals presented obvious pollution with I Hg of 0.64~1.36 (moderately polluted), I Cd of 1.66~2.22 (moderately to heavily polluted), and I As of 1.21~2.07 (moderately to heavily polluted). The heavy metal pollution states followed the order Cd > As > Hg > Cu > Pb > Zn > Cr, and the SPI showed that the sediment collected from open water area was more polluted than those obtained from the tributaries and the river mouth. Cr, Cd, Hg, Pb, Cu, As, and Zn were mainly attributed to sediment weathering with Hg, Pb, and Cu and partially due to domestic sewage from the upper reaches. These results indicate that the more attention should be paid to the inner loads of sediment in order to achieve improvements in reservoir water quality after the control of external pollution.