Multifaceted Characterization for the Hepatic Clearance of Graphene Oxide and Size-Related Hepatic Toxicity.

Understanding the final fate of nanomaterials (NMs) in the liver is crucial for their safer application. As a representative two-dimensional (2D) soft nanomaterial, graphene oxide (GO) has shown to have high potential for applications in the biomedical field, including in biosensing, drug delivery, tissue engineering, therapeutics, etc. GO has been shown to accumulate in the liver after entering the body, and thus, understanding the GO-liver interaction will facilitate the development of safer bio-applications. In this study, the hepatic clearance of two types of PEGylated GOs with different lateral sizes (s-GOs: ~70 nm and l-GOs: ~300 nm) was carefully investigated. We found that GO sheets across the hepatic sinusoidal endothelium, which then may be taken up by the hepatocytes via the Disse space. The hepatocytes may degrade GO into dot-like particles, which may be excreted via the hepatobiliary route. In combination with ICP-MS, LA-ICP-MS, and synchrotron radiation FTIR techniques, we found that more s-GO sheets in the liver were prone to be cleared via hepatobiliary excretion than l-GO sheets. A Raman imaging analysis of ID/IG ratios further indicated that both s-GO and l-GO generated more defects in the liver. The liver microsomes may contribute to GO biotransformation into O-containing functional groups, which plays an important role in GO degradation and excretion. In particular, more small-sized GO sheets in the liver were more likely to be cleared via hepatobiliary excretion than l-GO sheets, and a greater clearance of s-GO will mitigate their hepatotoxicity. These results provide a better understanding of the hepatic clearance of soft NMs, which is important in the safer-by-design of GO.

[Comparison of initiation of antihypertensive therapy strategies for primary prevention of cardiovascular diseases in Chinese population: A decision-analytic Markov modelling study].

OBJECTIVE: To evaluate the health benefits and intervention efficiency of different strategies of initiating antihypertensive therapy for the primary prevention of cardiovascular diseases in a community-based Chinese population from the Chinese electronic health records research in Yinzhou (CHERRY) study. METHODS: A decision-analytic Markov model was used to simulate and compare different antihypertensive initiation strategies, including: Strategy 1, initiation of antihypertensive therapy for Chinese adults with systolic blood pressure (SBP) ≥140 mmHg (2020 Chinese guideline on the primary prevention of cardiovascular diseases); Strategy 2, initiation of antihypertensive therapy for Chinese adults with SBP ≥130 mmHg; Strategy 3, initiation of antihypertensive therapy for Chinese adults with SBP≥140 mmHg, or with SBP between 130 and 140 mmHg and at high risk of cardiovascular diseases (2017 American College of Cardiology/American Heart Association guideline for the prevention, detection, evaluation, and management of high blood pressure in adults); Strategy 4, initiation of antihypertensive therapy for Chinese adults with SBP≥160 mmHg, or with SBP between 140 and 160 mmHg and at high risk of cardiovascular diseases (2019 United Kingdom National Institute for Health and Care Excellence guideline for the hypertension in adults: Diagnosis and management). The high 10-year cardiovascular risk was defined as the predicted risk over 10% based on the 2019 World Health Organization cardiovascular disease risk charts. Different strategies were simulated by the Markov model for ten years (cycles), with parameters mainly from the CHERRY study or published literature. After ten cycles of simulation, the numbers of quality-adjusted life years (QALY), cardiovascular events and all-cause deaths were calculated to evaluate the health benefits of each strategy, and the numbers needed to treat (NNT) for each cardiovascular event or all-cause death could be prevented were calculated to assess the intervention efficiency. One-way sensitivity analysis on the uncertainty of incidence rates of cardiovascular disease and probabilistic sensitivity analysis on the uncertainty of hazard ratios of interventions were conducted. RESULTS: A total of 213 987 Chinese adults aged 35-79 years without cardiovascular diseases were included. Compared with strategy 1, the number of cardiovascular events that could be prevented in strategy 2 increased by 666 (95% UI: 334-975), while the NNT per cardiovascular event prevented increased by 10 (95% UI: 7-20). In contrast to strategy 1, the number of cardiovascular events that could be prevented in strategy 3 increased by 388 (95% UI: 194-569), and the NNT per cardiovascular event prevented decreased by 6 (95% UI: 4-12), suggesting that strategy 3 had better health benefits and intervention efficiency. Compared to strategy 1, although the number of cardiovascular events that could be prevented decreased by 193 (95% UI: 98-281) in strategy 4, the NNT per cardiovascular event prevented decreased by 18 (95% UI: 13-37) with better efficiency. The results were consistent in the sensitivity analyses. CONCLUSION: When initiating antihypertensive therapy in an economically developed area of China, the strategy combined with cardiovascular risk assessment is more efficient than those purely based on the SBP threshold. The cardiovascular risk assessment strategy with different SBP thresholds is suggested to balance health benefits and intervention efficiency in diverse populations.

Edge Graphitized Oxygen-Rich Carbon Based on Stainless Steel-Assisted High-energy Ball Milling for High-Capacity and Ultrafast Sodium Storage.

Oxygen doping is an effective strategy for constructing high-performance carbon anodes in Na ion batteries; however, current oxygen-doped carbons always exhibit low doping levels and high-defect surfaces, resulting in limited capacity improvement and low initial Coulombic efficiency (ICE). Herein, a stainless steel-assisted high-energy ball milling is exploited to achieve high-level oxygen doping (19.33%) in the carbon framework. The doped oxygen atoms exist dominantly in the form of carbon-oxygen double bonds, supplying sufficient Na storage sites through an addition reaction. More importantly, it is unexpected that the random carbon layers on the surface are reconstructed into a quasi-ordered arrangement by robust mechanical force, which is low-defect and favorable for suppressing the formation of thick solid electrolyte interfaces. As such, the obtained carbon presents a large reversible capacity of 363 mAh g-1 with a high ICE up to 83.1%. In addition, owing to the surface-dominated capacity contribution, an ultrafast Na storage is achieved that the capacity remains 139 mAh g-1 under a large current density of 100 A g-1 . Such good Na storage performance, especially outstanding rate capability, has rarely been achieved before.

C-Type Lectin Maintains the Homeostasis of Intestinal Microbiota and Mediates Biofilm Formation by Intestinal Bacteria in Shrimp.

Intestinal microbiota are closely related to host physiology. Over the long course of evolution and interaction, both commensal bacteria and their host have evolved multiple strategies to adapt to each other. However, in invertebrates, the regulatory mechanism of intestinal microbiota homeostasis is largely unknown. In the current study, a digestive tract-specific C-type lectin, designated as CTL33, was identified because of its abundance and response to bacteria in the intestine of kuruma shrimp (Marsupenaeus japonicus). Silencing of CTL33 expression led directly to intestinal dysbiosis, tissue damage, and shrimp death. CTL33 could facilitate biofilm formation by the intestinal bacteria. This function originated from its unique architecture, with a lectin domain responsible for bacteria recognition and a coiled coil region that mediated CTL33 dimerization and cross-linked the bacteria into a biofilm-like complex. By mediating the formation of a biofilm, CTL33 promoted the establishment of intestinal bacteria in intestine and maintained the homeostasis of the microbiota. Thus, to our knowledge, we demonstrated a new mechanism of C-type lectin-mediated biofilm formation by intestinal bacteria, providing new insights into intestinal homeostasis regulation in invertebrates.

Surface-driven fast sodium storage enabled by Se-doped honeycomb-like macroporous carbon.

Selenium (Se) is an ideal doping agent to modulate the structure of carbon materials to improve their sodium storage performance but has been rarely investigated. In the present study, a novel Se-doped honeycomb-like macroporous carbon (Se-HMC) is prepared by a surface crosslinking method using diphenyl diselenide as the carbon source and SiO2 nanospheres as the template. Se-HMC has a high Se weight percentage above 10%, with a large surface area of 557 m2 g-1. Owing to the well-developed porous structure in combination with Se-assisted capacitive redox reactions, Se-HMC exhibits surface-dominated Na storage behaviors, thus presenting large capacity and fast Na storage capability. To be specific, Se-HMC delivers a high reversible capacity of 335 mA h g-1 at 0.1 A g-1, and after an 800-cycle repeated charge/discharge test at 1 A g-1, the capacity is stable with no dramatic loss. Remarkably, the capacity remains 251 mA h g-1 under a very large current density of 5 A g-1 (≈20 C), demonstrating an ultrafast Na storage process. As far as we know, such a good rate performance has been rarely achieved for carbon anodes before.

Responses of microbial interactions and functional genes to sulfamethoxazole in anammox consortia.

Sulfamethoxazole (SMX) has been widely detected in various environments and its potential environmental risks have caused great concerns. However, the impact mechanism of SMX on microbial interactions among anammox consortia remain unknown. A long-term exposure experiments (140 d) was carried out to systematically examine the influence of SMX (0-1000 µg/L) on the anammox system, especially microbial network dynamics and variations of key metabolic genes. Results showed that anammox system could adapt to SMX below 500 µg/L and maintain a high nitrogen removal efficiency (NRE) of 85.35 ± 2.42%, while 1000 µg/L SMX significantly decreased the abundance of functional microbes and deteriorated denitrification performance with NRE dropped to 36.92 ± 15.01%. Co-occurrence network analysis indicated that 1000 µg/L SMX decreased the interactions between Proteobacteria and Chloroflexi and limited AnAOB from playing an important role as central nodes in the subnetwork of Planctomycetes. Metagenomics analysis found that genes associated with nitrogen removal (i.e., hdh, hzs, nirS, and hao) showed lower expression level after addition of SMX, while SMX-related ARGs (sul1 and sul2) increased by 1.22 and 2.68 times. This study provided us a relatively comprehensive perspective in response of microbial interactions and metabolic activity to various SMX concentrations.

Preparation and characterization of a novel blue-TiO2/PbO2-carbon nanotube electrode and its application for degradation of phenol.

In this study, we fabricated a blue-TiO2/PbO2-carbon nanotube (CNT) electrode in which blue TiO2 nanotube arrays (blue-TNA) served as the substrate for PbO2-CNT eletrodeposition. Scanning electron microscope (SEM) showed compact surface structure of the electrode. The ß-PbO2 crystal structure was detected by X-ray diffraction (XRD). The distribution of Pb, O, C, and Na elements on the electrode surface have been confirmed by X-ray photoelectron spectroscopy (XPS). Blue-TiO2/PbO2-CNT electrode had higher response current (213.12 mA), larger active surface area and lower charge transfer resistance (2.22 Ω/cm2) than conventional TiO2/PbO2-CNT electrode. The influences of current density, initial phenol concentration, initial solution pH, and Na2SO4 concentration on the electrochemical oxidation of phenol have been analyzed. The results showed that the 100 mg/L phenol could be destroyed completely after 210 min, and chemical oxygen demand (COD) removal rate was 89.3% within 240 min. Additionally, the electrode showed long actual lifetime (5468.80 hr) and low energy consumption (0.08 kWh/gCOD). A phenol degradation mechanism was proposed by analyzing the intermediate products with high-performance liquid chromatography-mass spectrometry (HPLC-MS). Importantly, the blue-TiO2/PbO2-CNT electrode exhibited superior stability and high degradation efficiency after 15 times reuse, demonstrating its promising application potential on phenol-containing wastewater treatment.

Guanine Nucleotide-Binding Protein G(i) Subunit Alpha 2 Exacerbates NASH Progression by Regulating Peroxiredoxin 1-Related Inflammation and Lipophagy.

BACKGROUND AND AIMS: NASH is an advanced stage of liver disease accompanied by lipid accumulation, inflammation, and liver fibrosis. Guanine nucleotide-binding protein G(i) subunit alpha-2 (GNAI2) is a member of the "inhibitory" class of α-subunits, and recent studies showed that Gnai2 deficiency is known to cause reduced weight in mice. However, the role of GNAI2 in hepatocytes, particularly in the context of liver inflammation and lipid metabolism, remains to be elucidated. Herein, we aim to ascertain the function of GNAI2 in hepatocytes and its impact on the development of NASH. APPROACH AND RESULTS: Human liver tissues were obtained from NASH patients and healthy persons to evaluate the expression and clinical relevance of GNAI2. In addition, hepatocyte-specific Gnai2-deficient mice (Gnai2hep-/- ) were fed either a Western diet supplemented with fructose in drinking water (WDF) for 16 weeks or a methionine/choline-deficient diet (MCD) for 6 weeks to investigate the regulatory role and underlying mechanism of Gnai2 in NASH. GNAI2 was significantly up-regulated in liver tissues of patients with NASH. Following feeding with WDF or MCD diets, livers from Gnai2hep-/- mice had reduced steatohepatitis with suppression of markers of inflammation and an increase in lipophagy compared to Gnai2flox/flox mice. Toll-like receptor 4 signals through nuclear factor kappa B to trigger p65-dependent transcription of Gnai2. Intriguingly, immunoprecipitation, immunofluorescence, and mass spectrometry identified peroxiredoxin 1 (PRDX1) as a binding partner of GNAI2. Moreover, the function of PRDX1 in the suppression of TNF receptor-associated factor 6 ubiquitin-ligase activity and glycerophosphodiester phosphodiesterase domain-containing 5-related phosphatidylcholine metabolism was inhibited by GNAI2. Suppression of GNAI2 combined with overexpression of PRDX1 reversed the development of steatosis and fibrosis in vivo. CONCLUSIONS: GNAI2 is a major regulator that leads to the development of NASH. Thus, inhibition of GNAI2 could be an effective therapeutic target for the treatment of NASH.

Microporous Carbon Nanospheres with Fast Sodium Storage Capability Enabled by Dominant Capacitive Behavior.

Hard carbon is considered one of the most promising anode candidates for sodium ion batteries but suffers from a moderate rate performance. Here, we design microporous carbon nanospheres using a novel hybrid monomer that simultaneously involves an organic moiety and an inorganic moiety as the starting unit. The inorganic moiety forms a continuous network, which serves as a 3D scaffold and a nanometer-scale template, then supports the off-collapse of the carbon skeleton and creates a well-developed microporous structure. In addition, the graphite microcrystal structure can be tailored by adjusting the heating treatment temperatures. The electrochemical study demonstrates that the microporous carbon nanospheres show dominant capacitive sodium storage behavior, thus presenting an outstanding rate performance. Even if a very high current density of 10 A g-1 is applied, the hard carbon anode can deliver a large capacity of 127 mAh g-1 with a considerable plateau capacity of 53 mAh g-1, which has rarely been obtained in previous publications. Besides, the carbon anode has a good cycling stability, and the capacity reached 210 mAh g-1 after 1000 cycles with a current density of 1 A g-1, showing no dramatic capacity loss.

Switchable, Reagent-Controlled C(sp3)-H Selective Iodination and Acetoxylation of 8-Methylquinolines.

An efficient Pd-catalyzed C(sp3)-H selective iodination of 8-methylquinolines is reported herein for the first time. Because of the versatility of organic iodides, the method offers a facile access to various C8-substituted quinolines. By slightly switching the reaction conditions, an efficient C(sp3)-H acetoxylation of 8-methylquinolines has also been enabled. Both approaches feature mild reaction conditions, good tolerance of functional groups, and a broad substrate scope.

Low-Illumination Image Enhancement in the Space Environment Based on the DC-WGAN Algorithm.

Owing to insufficient illumination of the space station, the image information collected by the intelligent robot will be degraded, and it will not be able to accurately identify the tools required for the robot's on-orbit maintenance. This situation increases the difficulty of the robot's maintenance in a low-illumination environment. We proposes a novel enhancement method for images under low-illumination, namely, a deep learning algorithm based on the combination of deep convolutional and Wasserstein generative adversarial networks (DC-WGAN) in CIELAB color space. The original low-illuminance image is converted from the RGB space to the CIELAB color space which is relatively close to human vision, to accurately estimate the illumination image, and effectively reduce the effect of uneven illumination. DC-WGAN is applied to enhance the brightness component by increasing the width of the generation network to obtain more image features. Subsequently, the LAB is converted into RGB space to obtain the final enhanced image. The feasibility of the algorithm is verified by experiments on low-illuminance image under general, special, and actual conditions and comparing the experimental results with four commonly used algorithms. This study lays a technical foundation for robot target recognition and on-orbit maintenance in a space environment.

Responses of microbial communities and their interactions to ibuprofen in a bio-electrochemical system.

Ibuprofen has caused great concerns due to their potential environmental risks. However, their removal efficiency and their effects on microbial interactions in bio-electrochemical system remain unclear. To address these issues, a lab-scale bio-electrochemical reactor integrated with sulfur/iron-mediated autotrophic denitrification (BER-S/IAD) system exposing to 1000 µg L-1 ibuprofen was operated for about two months. Results revealed that the BER-S/IAD system obtained efficient simultaneous denitrification (98.93%) and phosphorus (82.67%) removal, as well as an excellent ibuprofen removal performance (96.98%). Ibuprofen had no significant impacts on the nitrate (NO3--N) removal and the ammonia (NH4+-N) accumulation, but decreased the total nitrogen (TN) and total phosphorus (TP) removal efficiencies. MiSeq sequencing analysis revealed that ibuprofen significantly (P < 0.05) decreased the microbial community diversity and changed their overall structure. Some bacteria related to denitrification and phosphorus removal, such as Pseudomonas and Thiobacillus, decreased significantly (P < 0.05). Moreover, molecular ecological network (MEN) analysis revealed that ibuprofen decreased the network's size and complexity, and enhanced the negative correlations of Proteobacteria and Firmicutes. Besides, ibuprofen decreased the links of some keystone bacteria related to denitrification and phosphorus removal. This research could provide a new dimension for our comprehending of the responses of microbial communities and their interactions to ibuprofen in bio-electrochemical system.

Genome-wide association study using diversity outcross mice identified candidate genes of pancreatic cancer.

To understand the genetic causes of pancreatic cancer (PC), we conducted a genome-wide association study (GWAS) using the diversity outbred (DO) mice population to identify susceptibility genes underlying 7,12-dimethylbenzanthraene (DMBA) induced PC. The phenotype studied was the percent PC lesion area in the DO mice population. We genotyped 7851 SNP markers specifically designed for DO mice across the whole mouse genome. Four susceptibility genes with P values exceeding the genome-wide threshold for percent PC lesion area (P < 2.37 × 10-6) were identified, i.e., Epha4, Gpc5, Kcnj6, Arid1b. The most significant SNP of Gpc5 (UNC140360310) that is associated with PC lesion area in mice also significantly influences the Gpc5 expression, suggesting that this Gpc5 SNP exerts its role in PC through cis-regulating the gene expression of Gpc5. Together, our data supported that Gpc5 as a tumor suppressor gene involved in the etiology of PC.

Optimization Design and Flexible Detection Method of Wall-Climbing Robot System with Multiple Sensors Integration for Magnetic Particle Testing.

Weld detection is vital to the quality of ship construction and navigation safety, and numerous detection robots have been developed and widely applied. Focusing on the current bottleneck of robot safety, efficiency, and intelligent detection, this paper developed a wall-climbing robot that integrates multiple sensors and uses fluorescent magnetic powder for nondestructive testing. We designed a moving mechanism that can safely move on a curved surface and a serial-parallel hybrid flexible detection mechanism that incorporates a force sensor to solve the robot's safe adsorption and a flexible detection of the curved surface to complete the flaw detection operation. We optimized the system structure and improved the overall performance of the robot by establishing a unified mechanical model for different operating conditions. Based on the collected sensor information, a multi-degree of freedom component collaborative flexible detection method with a standard detecting process was developed to complete efficient, high-quality detection. Results showed that the developed wall-climbing robot can move safely and steadily on the complex facade and can complete the flaw detection of wall welds.

Disturbance Recognition and Collision Detection of Manipulator Based on Momentum Observer.

Increasing requirements for the safety of human-robot interaction and the cost-effectiveness of collision detection rapidly promote the development of collision detection technology without torque sensors. To address nonlinear disturbance factors in collision detection that may cause unstable or even incorrect detection, this paper proposed a research strategy that considered the friction as the disturbance term in manipulator motion for the collision detection. The manipulator joint disturbance model was established based on the LuGre dynamic friction model, and the external torque observer was designed based on the generalized momentum. Then, the friction measurement was realized using the external torque observer, and the model parameters were identified through the genetic algorithm. The collision detection can be reduced errors after the friction model by compensating the disturbance and can be applicable to variable working conditions. Finally, the accuracy of the constructed disturbance model and the performance of the proposed collision detection method were validated by the experimental studies.

Optimization Design and Flexible Detection Method of a Surface Adaptation Wall-Climbing Robot with Multisensor Integration for Petrochemical Tanks.

Recently, numerous wall-climbing robots have been developed for petrochemical tank maintenance. However, most of them are difficult to be widely applied due to common problems such as poor adsorption capacity, low facade adaptability, and low detection accuracy. In order to realize automatic precise detection, an innovative wall-climbing robot system was designed. Based on magnetic circuit optimization, a passive adaptive moving mechanism that can adapt to the walls of different curvatures was proposed. In order to improve detection accuracy and efficiency, a flexible detection mechanism combining with a hooke hinge that can realize passive vertical alignment was designed to meet the detection requirements. Through the analysis of mechanical models under different working conditions, a hierarchical control system was established to complete the wall thickness and film thickness detection. The results showed that the robot could move safely and stably on the facade, as well as complete automatic precise detection.

Chitosan-reduced graphene oxide composites with 3D structures as effective reverse dispersed solid phase extraction adsorbents for pesticides analysis.

Chitosan-reduced graphene oxide composites with 3D structures (3D CS-rGO) were prepared via a facile solvothermal synthetic strategy. The reduction of GO and crosslinking of rGO nanosheets with CS into 3D structures were achieved simultaneously in one step. The resulting 3D CS-rGO composite achieves high adsorption capacities of catechins, caffeine and pigments from tea acetonitrile extraction, especially for catechins, which is 10 times higher than that of GO (179.3 mg g-1vs. 18.7 mg g-1). The 3D CS-rGO composite exhibits the best removal efficiency of matrix interference in comparison to other traditional adsorbents, which could diminish the matrix effect on targeted pesticides by 1%-55%. A determination method of 70 kinds of pesticides is successfully established for tea based on 3D CS-rGO composite as an efficient reverse dispersed solid phase extraction adsorbent. The established method has the great advantages of operation simplicity, being time saving and high purification performance using only one kind and a low amount of adsorbent. 3D graphene based materials are expected to be promising adsorbents for sample pretreatment in trace contaminant analysis of complex food samples.

Estimation of continuous elbow joint movement based on human physiological structure.

OBJECTIVE: Human intention recognition technology plays a vital role in the application of robotic exoskeletons and powered exoskeletons. However, the precise estimation of the continuous motion of each joint represents a major challenge. In the current study, we present a method for estimating continuous elbow joint movement. METHODS: We developed a novel approach for estimating the elbow joint angle based on human physiological structure. We used surface electromyography signals to analyze the biomechanical properties of the muscle and combined it with physiological structure to achieve a model for estimating continuous motion. And a genetic algorithm was used to optimize unknown parameters. RESULTS: We performed extensive trials to verify the generalizability and effectiveness of this method. The trial types included elbow joint motion with single cycle trials, typical cycle trials, gradually increasing amplitude trials, and random movement trials for handheld loads of 1.25 and 2.5 kg. The results revealed that the average root-mean-square errors ranged from 0.12 to 0.26 rad, reflecting an appropriate level of estimation accuracy. CONCLUSION: Establishing a reasonable physiological model and applying an efficient optimization algorithm enabled more accurate estimation of the joint angle. The proposed method provides a theoretical foundation for robotic exoskeletons and powered exoskeletons to understand the intentions of human continuous motion.

Dynamic Parameter Identification for a Manipulator with Joint Torque Sensors Based on an Improved Experimental Design.

As the foundation of model control, robot dynamics is crucial. However, a robot is a complex multi-input-multi-output system. System noise seriously affects parameter identification results, thereby inevitably requiring us to conduct signal processing to extract useful signals from chaotic noise. In this research, the dynamic parameters were identified on the basis of the proposed multi-criteria embedded optimization design method, to obtain the optimal excitation signal and then use maximum likelihood estimation for parameter identification. Considering the movement coupling characteristics of the multi-axis, experiments were based on a two degrees-of-freedom manipulator with joint torque sensors. Simulation and experimental results showed that the proposed method can reasonably resolve the problem of mutual opposition within a single criterion and improve the identification robustness in comparison with other optimization criteria. The mean relative standard deviation was 0.04 and 0.3 lower in the identified parameters than in F1 and F3, respectively, thus signifying that noise is effectively alleviated. In addition, validation experimental curves were close to the estimation model, and the average of root mean square (RMS) is 0.038, thereby confirming the accuracy of the proposed method.

Characterization of bacterial community dynamics in a full-scale drinking water treatment plant.

Understanding the spatial and temporal dynamics of microbial communities in drinking water systems is vital to securing the microbial safety of drinking water. The objective of this study was to comprehensively characterize the dynamics of microbial biomass and bacterial communities at each step of a full-scale drinking water treatment plant in Beijing, China. Both bulk water and biofilm samples on granular activated carbon (GAC) were collected over 9months. The proportion of cultivable cells decreased during the treatment processes, and this proportion was higher in warm season than cool season, suggesting that treatment processes and water temperature probably had considerable impact on the R2A cultivability of total bacteria. 16s rRNA gene based 454 pyrosequencing analysis of the bacterial community revealed that Proteobacteria predominated in all samples. The GAC biofilm harbored a distinct population with a much higher relative abundance of Acidobacteria than water samples. Principle coordinate analysis and one-way analysis of similarity indicated that the dynamics of the microbial communities in bulk water and biofilm samples were better explained by the treatment processes rather than by sampling time, and distinctive changes of the microbial communities in water occurred after GAC filtration. Furthermore, 20 distinct OTUs contributing most to the dissimilarity among samples of different sampling locations and 6 persistent OTUs present in the entire treatment process flow were identified. Overall, our findings demonstrate the significant effects that treatment processes have on the microbial biomass and community fluctuation and provide implications for further targeted investigation on particular bacteria populations.