ABSTRACT
Evidence shows the relationships of individual environmental PAHs by their urinary metabolites with relative telomere length (RTL), which may be affected by biological gender differences. Since plasma parent PAHs are not metabolized, it may reflect human exposure to PAHs more realistically in daily life. Thus, exploring joint associations between plasma parent PAHs and RTL is urgent, which may identify the major contributor to its adverse effect. In this study, 2577 participants were obtained from the Henan Rural Cohort. The level of PAHs in blood samples was detected by gas chromatography coupled with tandem mass spectrometry. RTL in blood samples was detected by quantitative polymerase chain reaction. Generalized linear models or quantile g-computation were performed to evaluate the associations between the individual or a mixture of PAHs and RTL. Results from generalized linear models showed that each unit increment in BghiP value corresponded to a 0.098 (95%CI: 0.067, 0.129) increment in RTL for men; each unit increment in BaP, BghiP and Flu value corresponded to a 0.041 (95%CI: 0.014, 0.068), 0.081 (95%CI: 0.055, 0.107) and 0.016 (95%CI: 0.005, 0.027) increment in RTL for women. Results from quantile-g computation revealed that each one-quantile increment in the mixture of 10 PAHs corresponded to a 0.057 (95%CI: 0.021, 0.094) and 0.047 (95%CI: 0.003, 0.091) increment in RTL values of women and men, but these associations were mainly ascribed to three PAHs for women (BaP, Flu and BghiP) and men (BaP, BghiP and Pyr), respectively. Similar results were found in smoking men and cooking women without smoking. Our study found that exposure to 10 PAHs mixture was positively associated with RTL across gender, mainly attributed to Flu, BaP and BghiP, implicating that gender-specific associations may be ascribed to tobacco and cooking smoke pollution. The findings provided clues for effective measures to control PAHs pollutants-related aging disease.Clinical trial registration The Henan Rural Cohort Study has been registered at the Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699). Date of registration: 06 July 2015. http://www.chictr.org.cn/showproj.aspx?proj=11375 .
Subject(s)
Environmental Pollutants , Polycyclic Aromatic Hydrocarbons , Male , Humans , Female , Polycyclic Aromatic Hydrocarbons/analysis , Cohort Studies , Gas Chromatography-Mass Spectrometry , Environmental Pollutants/toxicity , Environmental Pollutants/analysis , Telomere/chemistryABSTRACT
BACKGROUND: Accurate and timely clinical laboratory critical values notification are crucial steps in supporting effective clinical decision making, thereby improving patient safety. METHODS: A closed-loop laboratory critical value notification system was developed by a multidisciplinary team of clinicians, laboratorians, administrators, and information technology experts. All the laboratory critical values that occurred at Beijing Tsinghua Changgung Hospital (BTCH, Beijing, China) from 2015 to 2019 were analyzed and studied retrospectively. RESULTS: The total number (ratio) of institutional laboratory critical values to all reported items at BTCH from 2015 to 2019 was 38 020/7 706 962 (0.49%). Percentage distribution points of critical value boundaries based on patients' test reports are 0.007% ~ 6.04% for low boundaries and 71.70% ~ 99.99% for high boundaries. After the intervention, the timely notification ratio, notification receipt ratio, and timely notification receipt ratio of critical values of ED, IPD, and total patients had increased, with a significant difference (P < .001). Five quality indicators, such as notification ratio, timely notification ratio, notification receipt ratio, timely notification receipt ratio, and clinician response ratio over a 5-year period, were 100%, 94%, 97%, 92%, and 99%, respectively. CONCLUSIONS: We enhanced the effectiveness of clinical laboratory critical values initiative notification by implementing a closed-loop system and intervening. Clinical critical values and quality indicators should be analyzed and monitored to avoid adversely affecting patient care.
Subject(s)
Clinical Laboratory Techniques , Laboratories/organization & administration , Ambulatory Care/organization & administration , China , Clinical Laboratory Techniques/standards , Electronic Health Records , Emergency Service, Hospital/organization & administration , Humans , Laboratories/standards , Quality Control , Retrospective Studies , Time FactorsABSTRACT
Dickkopf-1 (DKK1) is a secretory antagonist that can bind with the Wnt coreceptor to desensitize cells to canonical Wnt ligands. DKN-01 is a specific antibody targeting secreted DKK1, which has been investigated as a monotherapy or combination therapy for various malignant tumors, including gastric cancer (GC). Tumor-associated macrophages (TAMs) with high plasticity usually present M2 phenotype, which can promote tumor progression. The aim of this study was to investigate the effect of DKN-01 on macrophage polarization in GC and the underlying molecular mechanism. To ascertain the effect of DKN-01 on GC tumor growth, we established a tumor-bearing mouse model and found that DKN-01 treatment suppressed tumor growth efficiently. Through RNA-seq and pathway enrichment analysis, we identified that the differentially expressed genes after DKN-01 treatment are associated with tumor immune-related pathways. Macrophage polarization was assessed using immunohistochemistry and quantitative real-time polymerase chain reaction. DKN-01 and knockdown of DKK1 promoted M1 polarization and inhibited M2 polarization of macrophages, while DKK1 overexpression got the opposite results. Moreover, DKN-01 activated the cGAS/STING pathway, while the inactivation of cGAS-STING pathway using RU.521 reversed the inhibition of tumor growth in vivo and macrophage M2 polarization caused by DKN-01. This study reveals that DKN-01 suppresses GC tumor growth through activating cGAS-STING pathway to block macrophage M2 polarization.
ABSTRACT
We present a case involving a 71-year-old male with tubulocystic renal cell carcinoma (TRCC), which is a rare entity of renal neoplasm. The patient was admitted for a cystic nodule on the middle pole of the right kidney by urological ultrasound during physical examination. The nodule presented with hyperechoic on conventional ultrasonic and the enhancing intensity of thicken cystic wall at the peak phase in contrast-enhanced ultrasound was similar to that of the renal parenchyma. Findings from computed tomography angiography exhibited heterogeneously contrast enhancing tumor, and magnetic resonance imaging demonstrated hypointense on T1-weighted images (WI) and hyperintense on T2WI. Histologically, the spongy surface was composed of the typical tubular and multiloculated cystic components lined by a single layer of epithelial cells. The final pathological diagnosis was TRCC. The uneventful laparoscopic right radical nephrectomy was conducted. The patient was followed up for 12 months after discharge and no signs of local or distant metastasis were found. In conclusion, TRCC should be accurately diagnosed on the basis of comprehensive radiological and histological findings to ensure a timely surgery and better prognosis.
ABSTRACT
Biotransformation is one of the dominant processes to remove organic micropollutants (OMPs) in wastewater treatment. However, studies on the role of molecular structure in determining the biotransformation rates of OMPs are limited. We evaluated the biotransformation of 14 OMPs belonging to different chemical classes under aerobic and anaerobic conditions, and then explored the quantitative structure-biotransformation relationships (QSBRs) of the OMPs based on biotransformation rates using valid molecular structure descriptors (electrical and physicochemical parameters). Pseudo-first-order kinetic modeling was used to fit the biotransformation rate, and only 2 of the 14 OMPs showed that the biotransformation rate constant (kbio) values were higher under anaerobic conditions than aerobic conditions, indicating that aerobic conditions were more favorable for biotransformation of most OMPs. QSBRs infer that the electrophilicity index (ω) is a reliable predictor for OMPs biotransformation under aerobic conditions. ω corresponds to the interaction between OMPs and microbial enzyme active sites, this process is the rate-limiting step of biotransformation. However, under anaerobic conditions the QSBR based on ω was not significant, indicating that specific functional groups may be more critical than electrophilicity. In conclusion, QSBRs can serve as alternative tools for the prediction of the biotransformation of OMPs and provide further insights into the factors that influence biotransformation.
Subject(s)
Water Pollutants, Chemical , Water Purification , Wastewater , Sewage/chemistry , Waste Disposal, Fluid , Water Pollutants, Chemical/metabolism , Anaerobiosis , BiotransformationABSTRACT
Biofouling limits applications of membrane technology in wastewater treatment, but dosing additives to membrane tanks is an effective method to alleviate biofouling. In this study, biochar derived from corncob and pyrolyzed at 300, 500, and 700°C was dosed to determine the underlying anti-biofouling mechanism. The effects of the biochar on the membrane properties and foulant behavior were systematically investigated. The results showed that biochar delayed the occurrence of the fouling transition (0.5-3.0 h), and decreased the flux decline rate, thus achieving a higher water flux (3.1-3.7 times of the control group). Biochar altered membrane surface properties, and increased the membrane surface charge, roughness, and hydrophilicity, which all contributed to higher membrane permeability. Moreover, adding biochar reduced the number of foulants in the fouling layer, particularly protein substances. The flux model fit and the XDLVO theory further revealed the mitigating effect of biochar on membrane biofouling. At the initial intermediate-blocking stage, the effect of biochar on membrane fouling was determined by its properties, and adsorption capacity to the foulants, BC500 presented the best mitigation performance. At the later cake-filtration stage, the role of biochar in membrane fouling was strongly associated with protein content in the fouling layer, and the minimum rate of flux decline occurred in BC300. This study promotes the understanding and development of biochar to alleviate membrane biofouling.
Subject(s)
Biofouling , Charcoal , Water Purification , Biofouling/prevention & control , Pyrolysis , Temperature , Membranes, Artificial , Water Purification/methodsABSTRACT
Extracellular polymeric substances (EPS) participate in the removal of organic micropollutants (OMPs), but the primary pathways of removal and detailed mechanisms remain elusive. We evaluated the effect of EPS on removal for 16 distinct chemical classes of OMPs during anaerobic digestion (AD). The results showed that hydrophobic OMPs (HBOMPs) could not be removed by EPS, while hydrophilic OMPs (HLOMPs) were amenable to removal via adsorption and biotransformation of EPS. The adsorption and biotransformation of HLOMPs by EPS accounted up to 19.4 ± 0.9 % and 6.0 ± 0.8 % of total removal, respectively. Further investigations into the adsorption and biotransformation mechanisms of HLOMPs by EPS were conducted utilizing spectral, molecular dynamics simulation, and electrochemical analysis. The results suggested that EPS provided abundant binding sites for the adsorption of HLOMPs. The binding of HLOMPs to tryptophan-like proteins in EPS formed nonfluorescent complexes. Hydrogen bonds, hydrophobic interactions and water bridges were key to the binding processes and helped stabilize the complexes. The biotransformation of HLOMPs by EPS may be attributed to the presence of extracellular redox active components (c-type cytochromes (c-Cyts), c-Cyts-bound flavins). This study enhanced the comprehension for the role of EPS on the OMPs removal in anaerobic wastewater treatment.
Subject(s)
Biotransformation , Extracellular Polymeric Substance Matrix , Wastewater , Water Pollutants, Chemical , Wastewater/chemistry , Adsorption , Anaerobiosis , Water Pollutants, Chemical/metabolism , Water Pollutants, Chemical/chemistry , Extracellular Polymeric Substance Matrix/metabolism , Extracellular Polymeric Substance Matrix/chemistry , Waste Disposal, Fluid/methods , Water Purification/methods , Hydrophobic and Hydrophilic Interactions , Molecular Dynamics SimulationABSTRACT
Objectives: Myocardial layer-specific strain is a sensitive tool for detecting myocardial dysfunction. The objective of this study was to assess changes in the left ventricle (LV) function using myocardial layer-specific strain and its association with 10-year atherosclerotic cardiovascular disease risk (10Y-ASCVDR) in individuals with hypertension (HP). Methods: The parameters of LV structure, including layer-specific global longitudinal strain (GLSww, GLSendo, GLSmid, GLSepi) and layer-specific global circumferential strain (GCSww, GCSendo, GCSmid, GCSepi), were analyzed by two-dimensional speckle-tracking echocardiography in 239 hypertensive patients and 124 control subjects. In addition, participants were divided into low-risk (LR) and high-risk (HR) subgroups according to 10Y-ASCVDR scores . The correlation between myocardial layer-specific strain and 10Y-ASCVDR was further analyzed by the restricted cubic spline (RCS) function. Results: The values of GLSww, GLSepi, GLSmid, and GLSendo were significantly lower in HP patients with HR than in HP patients with LR and controls (p < 0.05). However, no significant differences in layer-specific GCS were observed between the groups (p > 0.05). RCS analysis revealed that 10Y-ASCVDR exhibited a significant J-shaped relationship with layer-specific GLS and GCS. After adjusting for confounding factors, GLSww (ß = 0.156, p = 0.042), GLSmid (ß = 0.161, p = 0.032), GCSendo (ß = 0.163, p = 0.024), and GCSmid (ß = -0.175, p = 0.030) were identified as independent influencing factors for high 10Y-ASCVDR. Conclusions: In hypertensive patients, myocardial layer-specific strain, especially GLS, sensitively detected LV dysfunction and showed a significant J-shaped relationship with 10Y-ASCVDR. GCSmid may have a compensatory effect on myocardial impairment. LV myocardial layer-specific strain may help to understand the early compensatory mechanisms of the myocardium in hypertension.
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Terrain plays a critical role in the selection of cropland. As a physical and geographical element of the landscape, terrain is an important limiting factor in land use change and has a strong influence on human activities. The objectives of this study are to investigate the topographic characteristics of cropland-related transformations in China during the first decade of the 21st century and to explore the implications of land use change as it relates to securing a national food supply. A 2010 satellite-based land use dataset and the DEM data were used to conduct spatial statistical analysis using altitude, slope, and fragmentation data. The results showed the following. (1) As the urbanization and industrialization of China occur, and China attempts to replace this occupied cropland with newly reclaimed cropland, the topography of the most recently reclaimed cropland has been more poorly suited to farming than the topography of the occupied cropland it replaces in most provinces. (2) The area of occupied cropland was much larger than of those reclaimed; the qualities of occupied and reclaimed cropland were significantly different. (3) Land reclamation mainly occurred in northern China, instead of in southern China, which has a higher level of economic development. Our findings imply that the potential area available for cropland production may be limited.
Subject(s)
Agriculture , Crops, Agricultural , Food Supply , Agriculture/economics , Agriculture/history , Agriculture/trends , China , Crops, Agricultural/economics , Crops, Agricultural/growth & development , Crops, Agricultural/history , Food Supply/economics , Food Supply/history , History, 21st Century , HumansABSTRACT
Northern high-latitude permafrost holds the largest soil carbon pool in the world. Understanding the responses of permafrost to wildfire is crucial for improving our ability to predict permafrost degradation and further carbon emissions. Recently, studies have demonstrated that wildfires in the pan-Arctic region induced the thickening of the active layer based on site or fire event observations. However, how this induced thickening is influenced by vegetation and permafrost types remains not fully understood due to the lack of wall-to-wall analysis. Therefore, this study employed remotely sensed fire data and modelled active layer thickness (ALT) to identify the fire-induced ALT change (ΔALT) for the pan-Arctic region, and the contributions of vegetation and permafrost were quantified using the random forest (RF) model. Our results showed that the average ΔALT and the sensitivity of ΔALT to burn severity both increased with decreasing ground ice content in permafrost. The largest values were detected in thick permafrost with low ground ice content. Regarding vegetation, the average and sensitivity of ΔALT in tundra were highest, followed by those in forest and shrub. When the individual environmental factors were all taken into account, the results showed that the contribution of vegetation types was much higher than that of permafrost types (20.2 % vs. 3.5 %). Our findings highlighted the importance of environmental factors in regulating the responses of permafrost to fire.
Subject(s)
Permafrost , Wildfires , Ice , Taiga , Soil , Arctic Regions , CarbonABSTRACT
OBJECTIVE: To compare the consistency between superb microvascular imaging (SMI) and contrast-enhanced ultrasound (CEUS) for the detection of neovascularization in carotid plaques of different thicknesses and to evaluate the applied value of these two methods for detecting neovascularization in carotid plaques in the clinic. METHODS: A total of 45 patients with carotid artery plaques who were diagnosed in our hospital involving 76 hypoechoic plaques with a thickness ≥2.0 mm were selected. According to thickness, the plaques were divided into three groups: 2.0-2.5 mm, 2.5-3.0 mm and ≥3.0 mm. Each group underwent both SMI and CEUS, and two experienced sonographers (A and B) analyzed the ultrasound images to evaluate the neovascularization of carotid plaques. The amount of the neovascular signal was assessed using a semi-quantitative grading scale (vascularity grade: grade 0-3). SMI and CEUS were graded respectively according to the visual methods as follows: grade 0: no blood flow signal/enhancement within plaques; grade 1: a few blood flow signals/enhancement within plaques; grade 2: medium blood flow signals/enhancement within plaques; and grade 3: extensive blood flow signals/enhancement within plaques. Kappa consistency test was used to analyze the consistency of the grade of neovascularization in plaques between SMI with CEUS. Gamma rank correlation analysis was used to examine the correlation between neovascularization grade by SMI and CEUS in plaque and plaque thickness. RESULTS: Of these patients, 14 had unilateral plaques and 31 had bilateral plaques. The two sonographers were highly consistent in terms of applying SMI and CEUS methods for diagnosing neovascularization in carotid plaques (Kappa values were 0.736 and 0.680>0). Consistency was found between SMI and CEUS by sonographers (sonographer A: Kappa=0.823; sonographer B: Kappa=0.842) in evaluating the neovascular grade in the carotid plaques. SMI and CEUS grades were positively correlated with plaque thickness (sonographer A: γ = 0.735 and 0.772; sonographer B: γ = 0.805 and 0.798). CONCLUSION: Neovascularization in carotid plaques was successfully detected by SMI in a manner that concurred well with CEUS results. Our data indicate that both CEUS and SMI have high diagnostic value for assessing the neovascularization of plaques.
Subject(s)
Carotid Stenosis , Plaque, Atherosclerotic , Humans , Carotid Stenosis/diagnostic imaging , Contrast Media , Ultrasonography/methods , Ultrasonography, Doppler , Carotid Arteries/diagnostic imaging , Plaque, Atherosclerotic/diagnostic imaging , Neovascularization, Pathologic/diagnostic imagingABSTRACT
Persulfate activation is an efficient advanced oxidation process for water treatment. However, many catalyst materials make their preparation methods and raw materials very complicated and expensive while pursuing high-efficiency catalytic effects. In this research, a novel Co-modified micro/nano geopolymer (Co-MNG) material was prepared from solid waste using a mechanochemical method. The whole preparation process of Co-MNG is simple and time-saving, and most of its raw materials are solid waste. In addition, it has few adverse effects on the environment during preparation and use and has a good effect on PDS activation. Under dark conditions, 1 mg L-1 of unloaded Co metal MNG material could degrade 20 mg L-1 Rhodamine B solution by 79% in 60 min with 15 mM PDS, but the application of visible light could not enhance its effect. However, after adding 4 wt% of different Co-containing compounds, the prepared Co-MNG materials could improve their degradation effect under the same conditions, and it is more obvious under the condition of applying visible light. Among them, MNG-Co(NO3)2 could completely degrade RhB within 40 min under the application of visible light. ESR (electron spin resonance) tests showed that the MNG-Co(NO3)2 material could generate a variety of active radicals in a photo-PDS system, such as h+, ·OH, ·O2- and SO4-. Mechanistic research experiments showed that both visible light and Co-MNG materials can activate PDS to a certain extent, but when both exist at the same time, the material could effectively couple visible light and Co activation of PDS in a photo-PDS activation system to achieve synergistic degradation of pollutants in water.
Subject(s)
Environmental Pollutants , Water Pollutants, Chemical , Water Purification , Catalysis , Solid Waste , Water Pollutants, Chemical/analysisABSTRACT
In order to obtain an adsorbent-photocatalyst with low-cost, strong stability and great reusability/recyclability, a waste-based and CdS-loaded hierarchically porous geopolymer (HPG) was prepared by facile synthesis. The adsorption-photocatalysis ability, reusability, and stability of HPG under different conditions were determined. Results indicated that HPG showed better adsorption-photocatalysis performance for organic dyes under alkaline environment, and it remained a high adsorption-photocatalysis efficiency after used for five times. Furthermore, HPG was stable in different environment conditions (strong acidic, acid raining, neutral, high salinity, and high alkali environment). The mass loss of HPG were around 3.22-6.68% (7 days extraction), and the immobilization rates of Cd2+ in neutral, high salinity, and high alkali environments were higher than 99.99%. Under visible light irradiation, HPG effectively photo-degraded the organic substances in overlying water of polluted sediments. After 330 min irradiation, the concentrations of COD and TOC were decreased from 47.52 mg/L and 20.9 mg/L to 16.58 mg/L and 11.19 mg/L, respectively. The humic-like and fulvic-like substances were transformed to protein-like substances under photo-degradation effect. This study confirmed that HPG possesses advantages in cost, chemical stability, and reusability, and it has a great potential to be used as in-situ remediation environmental functional material for organic contaminants in lake.
Subject(s)
Cadmium , Coloring Agents , Adsorption , Alkalies , Porosity , WaterABSTRACT
To examine the short-term effects of biochar on the partial-denitrification anammox (PD/A) process, the adsorption kinetics, nitrogen degradation, electron transfer properties, and microbial community succession of wastewater treatment systems with and without biochar added were monitored and characterized. The results showed that biochar increased nitrate reduction rates, which enhanced total nitrogen (TN) removal of the system by about 10%. The findings attributed improved TN removal to biochar's influence in accelerating electron transfer rather than its adsorption properties. Analysis of the nitrogen transfer pathway showed that when sufficient substrate was available, the anammox and denitrification reactions simultaneously removed nitrogen. When the nitrite supply was insufficient, the anammox reaction outcompeted the denitrification reaction for regenerated nitrite. Integrated microbial community and functional protein analyses indicated that biochar addition increased the abundance of Ca. Kuenenia and Pseudomonas. Meanwhile, biochar modulates denitrifying cellular metabolism by inducing protein changes.
Subject(s)
Denitrification , Nitrates , Anaerobic Ammonia Oxidation , Bioreactors , Charcoal , Nitrites , Nitrogen , Oxidation-Reduction , Sewage , Wastewater/chemistryABSTRACT
Cadmium (Cd) toxicity not only affects plant growth and development, but also affects human health through the food chain. Several studies have demonstrated that Selenium (Se) alleviates Cd stress in plants; however, whether and how Se-alleviated Cd stress by regulating the structure of soil microbial community remain largely unclear. Here, we investigated the alleviating effects of exogenous applied Se (foliar spraying or root application) on plant growth under Cd stress in perilla (Perilla frutescens L.) by measuring the biomass, photosynthetic fluorescence parameters, root cell wall components and soil microbial community structure and diversity. Under Cd stress, perilla seedlings supplemented with Se increased chlorophyll content. Foliar spraying Se increased the levels of relative chlorophyll content (ΦII), photosynthetic system II (ΦPSII) and electron transport rate (ETR) in perilla leaves under Cd stress; while, root application of Se increased the levels of photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), water use efficiency (WUE) and stomatal limitation value (Ls) under Cd stress. Compared with Cd toxicity alone, root application of Se increased the contents of hemicellulosic 1 and hemicellulosic 2 in the cell wall of perilla roots. Cd toxicity or root application of Se did not affect soil bacterial community diversity. Root application of Se increased the relative abundance of Proteobacteria, Bacteroidetes, Fibrobacteres, Sphingomonas and Nitrosospira in Cd-contaminated soil, and thereby improving soil microbial community structure, finally promoting the growth of perilla seedlings.
ABSTRACT
Single-stage partial nitration and anammox (PN/A) process was achieved in a sequencing batch reactor (SBR) using a submerged dynamic membrane (DM) in this study. The reactor was stably operated for 200 days, and the nitrogen removal efficiency (NRE) was sustained at 70.3 ± 7.2% at a nitrogen loading rate (NLR) ranging from 0.1 to 0.3 kgNm-3 day-1 with a hydraulic retention time (HRT) of 24 hr. When the NLR was 0.2 kgN m-3 day-1 , the NRE achieved was high as 80% with a low concentration of dissolved oxygen (DO) of 0.13 mg/L. In addition, the specific activity of anammox bacteria and ammonia-oxidizing bacteria (AOB) reached was 2.72 and 16.80 gN gVSS-1 day-1 , respectively. The DM intercepted the biomass due to the lamellar, intact, dense biofilm self-generated on the surface of the supporting material, which had an effluent turbidity of 10 NTU. The enriched anammox functional bacteria were Candidatus Jettenia (11.06%) and the AOB-like functional bacteria consisted primarily of Nitrosomonas, with a relative abundance of 2.76%, which ensured the PN/A process proceeding. This study provides a novel reactor configuration of the single-stage PN/A process in the view of practical applications. PRACTITIONER POINTS: Single-stage partial nitration and anammox (PN/A) process was achieved using a submerged dynamic membrane (DM) in this study. The reactor was stably operated for 200 days, and the nitrogen removal efficiency was sustained at 70.3 ± 7.2%. The feasibility of the PN/A system with DM is evaluated. The main objective is to provide a control strategy of the DM-SBRs for practical applications.
Subject(s)
Ammonium Compounds , Bacteria , Bioreactors , Nitrogen , Oxidation-Reduction , WastewaterABSTRACT
Spatially explicit information on electric power consumption (EPC) is crucial for effective electricity allocation and utilization. Many studies have estimated fine-scale spatial EPC based on remotely sensed nighttime light (NTL). However, the spatial non-stationary relationship between EPC and NTL at prefectural level tends to be overlooked in existing literature. In this study, a classification regression method to estimate the gridded EPC in China based on imaging NTL via a Visible Infrared Imaging Radiometer Suite (VIIRS) was described. In addition, owing to some inherent omissions in the VIIRS NTL data, the study has employed the cubic Hermite interpolation to produce a more appropriate NTL dataset for estimation. The proposed method was compared with ordinary least squares (OLS) and geographically weighted regression (GWR) approaches. The results showed that our proposed method outperformed OLS and GWR in relative error (RE) and mean absolute percentage error (MAPE). The desirable results benefited mainly from a reasonable classification scheme that fully considered the spatial non-stationary relationship between EPC and NTL. Thus, the analysis suggested that the proposed classification regression method would enhance the accuracy of the gridded EPC estimation and provide a valuable reference predictive model for electricity consumption.
ABSTRACT
The extract of crofton weed (Eupatorium adenophorum) inhibits seed germination and weed growth; however, the physiological mechanisms underlying the effect of crofton weed extract on the modulation of seedling growth and root system development remain largely unclear. In this study, we investigated the effects of the leaf extract of crofton weed (LECW) on primary root (PR) growth in maize seedlings. Treatment with LECW markedly inhibited seed germination and seedling growth in a dose-dependent manner. Physiological analysis indicated that the LECW induced reactive oxygen species (ROS) accumulation in root tips, thereby leading to cell swelling and deformation both in the root cap and elongation zone of root tips, finally leading to cell death in root border cells (RBCs) and PR growth inhibition. The LECW also inhibited pectin methyl esterase (PME) activity, thereby decreasing the RBC number. Taken together, our results indicated that the LECW inhibited PR growth by inducing ROS accumulation and subsequent cell death in RBCs. The present study provides a better understanding of how the LECW modifies root system development and provides insight for evaluating the toxicity of crofton weed extracts in plants.
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The spatial distribution of population is closely related to land use and land cover (LULC) patterns on both regional and global scales. Population can be redistributed onto geo-referenced square grids according to this relation. In the past decades, various approaches to monitoring LULC using remote sensing and Geographic Information Systems (GIS) have been developed, which makes it possible for efficient updating of geo-referenced population data. A Spatial Population Updating System (SPUS) is developed for updating the gridded population database of China based on remote sensing, GIS and spatial database technologies, with a spatial resolution of 1 km by 1 km. The SPUS can process standard Moderate Resolution Imaging Spectroradiometer (MODIS L1B) data integrated with a Pattern Decomposition Method (PDM) and an LULC-Conversion Model to obtain patterns of land use and land cover, and provide input parameters for a Population Spatialization Model (PSM). The PSM embedded in SPUS is used for generating 1 km by 1 km gridded population data in each population distribution region based on natural and socio-economic variables. Validation results from finer township-level census data of Yishui County suggest that the gridded population database produced by the SPUS is reliable.
ABSTRACT
To understand the relationship between microbes and digester performance of high-frequency feeding CSTR, which could achieve stable CH4 production at high OLR by easing instantaneous feeding shock, attentions were paid on the variations of methanogenic capacity (MC) and microbial community with OLR increasing. Results showed that the MC for feedstock degradation could satisfy the need of effective conversion from feedstock to CH4 when the OLR remained below 16.4â¯g-TS/L/d. Furthermore, the MC for acetate, propionate and butyrate degradation increased by 73.8%, 303%, and 164%, respectively, with OLR increasing from 3.03â¯g-TS/L/d 12.6â¯g-TS/L/d. The evolution of both bacterial and archaeal communities provided additional information on the adaptation of functional microbes to environmental factors. The significant increase of abundance of Methanoculleus and Methanomassiliicoccus likely promoted the utilization of H2, thus facilitating syntrophic methanogenesis, and consequently ensuring efficient CH4 production in stable stage.