•Data quality and number of parameters are considered in kinetic and equilibrium model selection.•The rank of adsorption capacity is: Loamy sand, sandy loam, silty loam clay, and loam.•Two-site ...chemical non-equilibrium transport model best describes Cr (VI) breakthrough curves.•Sediment grain sizes and clay mineral contents are key factors for Cr (VI) adsorption.
Transport of hexavalent chromium, Cr (VI), in groundwater is largely influenced by adsorption and desorption processes. Sediment types can result in substantial difference in adsorption mechanisms. The goal of this work is to explore the adsorption mechanism of Cr (VI) within sediments with different properties and to identify the controlling factors. In this paper, Cr (VI) adsorption onto six different natural unconsolidated sediments (two loamy sands, two sandy loams, one loam, and one silty loam clay) collected from a typical fluvial aquifer in Qiqihar, China, was assessed with batch and column experiments. Equilibrium adsorption capacities and kinetic rates were quantified with batch experiments. Potential controlling effects of pH, solid/solution ratio, grain size, and clay mineral content on adsorption capacities were also analyzed. Adsorption kinetics was evaluated with Elovich, pseudo first- and second-order models, and equilibrium properties were assessed with Henry, Freundlich, and Langmuir isotherms. Model adequacy was discriminated with selection criteria of Akaike information criterion (AIC), modified Akaike information criterion (AICc), Bayesian information criterion (BIC), and Hannan information criterion (HIC). Adsorption and desorption of Cr (VI) onto and from the collected sediment samples under flow conditions were investigated with column experiments. Key results suggest that irreversible chemical adsorption is the dominant mechanism for Cr (VI) adsorption onto the sediment samples. Grain sizes and clay mineral contents are the controlling factors for adsorption capacity. Fine-grained sediments with high clay mineral contents present the highest Cr (VI) adsorption capacity. Chromium (VI) presents high retention on loam and silty loam clay, and high mobility on loamy sand. Results from this study may provide important insight for understanding the transport behaviors of Cr (VI) in shallow aquifers.
Pentagalloyl glucose (PGG) has been studied for its valuable biological activities. However, the functional role of PGG in lipid metabolism in vivo is unclear. Here, we investigated the effects of ...PGG on lipid metabolism and its underlying mechanism in Caenorhabditis elegans. PGG decreased the accumulation of reactive oxygen species at 800 μM and remarkably increased the activities of antioxidant enzymes. PGG decreased significantly fat accumulation in wild-type worms (39.7 ± 5.7% in the normal group and 19.9 ± 4.5% in the high-fat group by Oil red O; 21.2 ± 2.7% in the high-fat group by Nile red; p < 0.001), but fat reduction by PGG was eliminated in the skn-1 mutant. The amount and size of lipid droplets in the ZXW618 mutant were decreased by PGG. The proportions of unsaturated fatty acids in both conditions were increased by PGG. In addition, the expression levels of fat metabolism genes were significantly changed in both conditions by PGG, which include mdt-15, pod-2, elo-2, fat-6, and fat-7 genes modulated fat synthesis; aak-2 and nhr-49 genes participated in fat consumption; and tub-1 gene regulated fat storage. However, fat-5 and acs-2 were downregulated in high-fat worms only, and vit-2 and lipl-4 were downregulated in normal worms only. Our study provided new insights into the role of PGG in alleviating fat accumulation and its underlying mechanism of action in C. elegans.
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•Three different resolution of indicator data was used to simulate plume dispersion.•The dispersivity is underestimated with less indicator ...data.•Longitudinaldispersivityismostsensitivetotheindicatorintegralscale.•Theanisotropyratioisthemostsensitiveparametersfortransversedispersivity.
The potential impacts of the spatial resolution of sedimentary structure data on solute dispersion in heterogeneous porous formations are investigated with Lagrangian-based transport models. The models rely on a covariance function that represent a hierarchical organization of sedimentary facies types by using facies physical properties, such as volume proportions and mean length as well as auto- and cross-transition probabilities and their log-permeability covariance. A detailed sedimentary architecture data (i.e. indicator data) provides better representation of the spatial correlation structures of the global covariances through capturing its underlying structure defined by transition probabilities more accurately. However, the extent to which such data affect time-dependent transport parameters (i.e. dispersivity) is unclear. In this study, we parameterize transport models using detailed collocated sedimentary architecture and permeability data from an outcrop in Española Basin, NM. In addition, we perform global sensitivity analysis based on Polynomials Chaos Expansion to understand the significance of parameters in the transport models. The results show that dispersivity and particle displacement variance are under-estimated if less resolved facies (i.e. indicator) data are used even if the global covariance structure is well captured. Dispersivity is sensitive to the correlation scale that is directly calculated from sedimentary architecture data, and the mean log-permeability. However, anisotropy ratio and mean log-permeability are the most sensitive parameters for the transverse dispersivity.
Acoustic tomography is an important test method in engineering geology and underground engineering, however, the problems of model parameterization, forward modeling and inversion in the process of ...tomographic imaging still need further study. In this work, the triangulation method of two-dimensional complex area was studied and the global algorithm of triangular ray tracing in two-dimensional complex area was formulated. Numerical simulation results of triangular acoustic ray tomography show that with the increase of iteration times, the ray tracing becomes increasingly close to the ray-tracing forward from the velocity model; through seven iterations, the low-speed plate with a thickness of only 0.56 m can also be clearly reflected. Besides, based on triangular ray-tracing tomography of the two-dimensional complex structure, the deep acoustic detection of coal seam floor failure zone is carried out. After the initial velocity model is determined by the single-hole acoustic detection results, the velocity distribution of the floor between holes is obtained by triangular network acoustic tomography from the premining, mid-mining and postmining acoustic penetration detection. Field measurements show that the 17-m-span acoustic wave penetration is successfully realized in sandstone and mudstone strata of coal seam floor, with accurate delineation of the development range of water-conducting fissures in floor failure. The triangular acoustic tomography method makes full use of the characteristics of flexible model division and makes the imaging results appear closer to the actual structural morphological characteristics.
Sulfonamide antibiotics (SAs) are widely used in medicine, animal husbandry and aquaculture, and excessive intake of SAs may pose potential toxicity to organisms. The toxicological mechanisms of two ...classical SAs, sulfamerazine (SMR) and sulfamethoxazole (SMT), were investigated by molecular docking, DFT and multi-spectroscopic techniques using HSA and BSA as model proteins. The quenching of HSA/BSA endogenous fluorescence by SMR was higher than that by SMT due to the stronger binding effect of the pyrimidine ring on HSA/BSA compared to the oxazole ring, and that result was consistent with that predicted by DFT calculations. Thermodynamic parameters show that the binding of SAs to HSA/BSA is an exothermic process that proceeds spontaneously (ΔG < 0). Marker competition experiments illustrate that the binding site of SMR/SMT on serum albumin is located in subdomain IIIA. The combination of SAs and HSA/BSA is mainly realized by hydrogen bond and hydrophobic interaction, and the concept is also supported by molecular modeling. The reduced α-helix content of HSA/BSA induced by SMR/SMT indicates a greater stretching of the protein α-helix structure of the SMR/SMT-HSA/BSA. The results could provide useful toxicological information on the hazards of SAs in response to growing concern that SAs may pose a toxic threat to organisms.
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•The toxicology of SAs was analyzed by DFT, molecular docking and spectroscopy.•Hydrophobic interactions and hydrogen bonding play a major role in complexes.•SMR and SMT can change the microenvironment and conformation of serum albumin.•The potential toxicity of the SMR was confirmed to be higher than that of the SMT.•The interaction between SMR/SMT and HSA/BSA can reduce the biological activity.
This paper discusses the analysis and research of library user behavior based on Apriori optimization algorithm. This algorithm can be used to analyze the borrowing behavior of users in the library. ...This article introduces the principle and process of the Apriori algorithm, and then performs data preprocessing and cleaning on the library borrowing records. Frequent itemsets and association rules are mined by using Apriori algorithm, and the results are explained and analyzed. The research results of this paper show that there is a certain correlation between the books borrowed by library users. According to the mining results of association rules, the library can recommend different books for different types of users, so as to improve user satisfaction and borrowing rate.
Timely diagnosis and appropriate antifungal therapy are critical for improving the prognosis of patients with invasive fungal disease (IFD) after hematopoietic stem cell transplantation (HSCT). We ...evaluated the performance of metagenomic next-generation sequencing (mNGS) and conventional microbiological testing (CMT), as well as the diagnosis, therapeutic management, and outcomes of IFD after HSCT.
We retrospectively studied 189 patients who underwent HSCT and were considered at risk for IFD. In total, 46 patients with IFD were enrolled in this study. The IFD consensus was followed for classifying IFD incidents.
Forty-six patients were diagnosed with proven/probable (n = 12), possible (n = 27), and undefined (n = 7) IFD.
was the most commonly detected fungal genus.
was found in 15 patients; two had
, and one had
infections. Compared to CMT, mNGS significantly reduced the time required to identify pathogens (
= 0.0016). mNGS had a much higher sensitivity than CMT (84.78% vs. 36.96%;
< 0.0001). A total of 76.09% of patients received antifungal prophylaxis during fungal infections. All
infections occurred later than 100 days after transplantation. Among patients with
infection, 71.43% occurred following sulfonamide withdrawal, and subsequent treatment with sulfonamide alone or in combination with other drugs was effective. Based on the empirical antifungal treatment, the dosages, modes of administration, frequency of administration, or antifungal of 55.26% of the patients were changed according to the mNGS results. The 4-year overall survival rate of patients diagnosed with IFD after transplantation was 71.55% (95% CI, 55.18%-85.82%). Hypoproteinemia and corticosteroid use are independent risk factors for IFD.
mNGS, which has a high sensitivity and a short detection time, aids in the diagnosis and prognosis of pathogenic fungi. As a powerful technology, mNGS can influence treatment decisions in patients with IFD following HSCT.
Early diagnosis and treatment of parasitic diseases are indispensable to combat parasites mediated morbidity and mortality in humans and animals. Mammalian sourced antibodies are being successfully ...used in immunotherapy and immunoassays. However, their increased conservation amongst mammals, involves them in unnecessary interaction and immune mediated pathologies, obstructing their applications in certain approaches in immunoassays. Further, the high production cost and difficulty to achieve high and stable antibody titer hampers their utility for therapeutic purposes. In recent years, chicken egg yolk immunoglobulin, termed as immunoglobulin Y (IgY) has attracted noticeable consideration since it poses greater advantages than mammalian IgG including high yield, low cost and convenience. IgY has unique properties which are being exploited in different aspects for its applications in research, diagnosis and therapy. This review gives an overview of the research outcomes pertaining to chicken IgY as diagnostics and therapeutics in parasitology.
•Polyclonal IgY against parasitic antigens are suitable for immunotherapeutic applications.•Further investigations with well-designed animal experiments are indispensable.•IgY based immunoassays could be a promising alternative to mammalian antibodies.•Preparation of monoclonal IgY against parasitic antigens would be an ideal focus.
With the increasing popularity of long-distance water supply projects and the development of materials technology, the variation of water hammer characteristics in the viscoelastic pipeline has ...become the focus of researchers. To find out the mechanism of water hammer in the viscoelastic pipe of both elastic and viscous properties, an experiment was set up to study the direct water hammer generated by rapid closure of the downstream valve in the polymethyl methacrylate (PMMA) pipe, with six flow velocities in nearly 70 tests. The experimental results showed that the maximum water hammer pressure generated in the viscoelastic pipe in all flow velocities was (20% at most) greater than the traditional value of Joukowsky's formula. A faster closing time of the valve caused a higher water hammer pressure. The difference in water hammer pressure generated between the fastest and the slowest closing time of the valve was 14–17% at each flow velocity. Based on the relationship between the stress and strain of the pipe wall in the viscoelastic pipe, the reason that the water hammer characteristic in the viscoelastic pipeline was different from the traditional value was explained. The study provides a reference for the mechanism of transient flow in viscoelastic pipelines. HIGHLIGHTS An experiment of direct water hammer generated by rapid closure of valve was conducted in a long and straight PMMA pipe.; Measured maximum water hammer pressure rise was 15–20% greater than the traditional value of Joukowsky's formula.; A faster closing time of the valve caused a higher direct water hammer pressure.;
Groundwater monitoring networks are direct sources of information for revealing subsurface system dynamic processes. However, designing such networks is difficult due to uncertainties in the spatial ...heterogeneity of aquifer parameters such as permeability (k). This study combines deep learning and information theory with an optimization framework to address network design problems in heterogeneous aquifer systems. The framework first employs a generative adversarial network to parameterize heterogeneous k distribution using a low‐dimensional latent representation. Then, surrogate models are developed based on the deep neural networks to perform uncertainty quantification of pressure heads and solute concentrations at locations of pre‐designed candidate monitoring stations. The monitoring stations are then ranked using the greedy search algorithm based on the maximum information minimum redundancy (MIMR) criterion. In order to depict the importance of each candidate monitoring location, the hotspot maps of the selection probability (Ps) are derived from MIMR repetition results. Comprehensive monitoring networks derived from the hotspot maps are then conducted as the final monitoring stations to improve monitoring information compared to MIMR results. Additionally, nine entropy quantization strategies are compared to evaluate their effects on monitoring network optimization results. Results indicate that caution should be taken when selecting entropy quantization strategies to achieve the accuracy required for model calibration and to improve the efficiency of monitoring optimization. Considering high‐dimensional uncertainties associated with aquifer parameters, the developed framework can provide important insights for monitoring network designs in various earth observational projects.
Plain Language Summary
Groundwater is widely distributed throughout the crust and lithosphere playing a critical role in geological evolution processes and environmental problems. This study presents an integrated framework for designing groundwater monitoring networks in heterogeneous aquifer systems. The proposed model takes advantage of the strength of deep‐learning algorithms and deals with high‐dimensional and highly non‐linear problems of entropy‐based methods for designing the monitoring networks. The framework can efficiently provide monitor locations for complex aquifers. The monitoring data collected by the designed network can significantly reduce uncertainties associated with high‐dimensional parameters and contain the least amount of redundant information. Further, the proposed method is significant in practice as credible groundwater forecasting requires model calibrations that use monitoring data.
Key Points
Effective designed monitoring networks are critical for reducing model uncertainties and properly reflecting subsurface dynamic processes
Deep learning and maximum information minimum redundancy criterion were combined to design optimal monitoring networks for heterogeneous aquifers
The designed monitoring networks were verified to be influenced by different entropy quantification strategies
