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1.
BMC Bioinformatics ; 22(1): 423, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34493210

RESUMO

BACKGROUND: Assessing the reproducibility of measurements is an important first step for improving the reliability of downstream analyses of high-throughput metabolomics experiments. We define a metabolite to be reproducible when it demonstrates consistency across replicate experiments. Similarly, metabolites which are not consistent across replicates can be labeled as irreproducible. In this work, we introduce and evaluate the use (Ma)ximum (R)ank (R)eproducibility (MaRR) to examine reproducibility in mass spectrometry-based metabolomics experiments. We examine reproducibility across technical or biological samples in three different mass spectrometry metabolomics (MS-Metabolomics) data sets. RESULTS: We apply MaRR, a nonparametric approach that detects the change from reproducible to irreproducible signals using a maximal rank statistic. The advantage of using MaRR over model-based methods that it does not make parametric assumptions on the underlying distributions or dependence structures of reproducible metabolites. Using three MS Metabolomics data sets generated in the multi-center Genetic Epidemiology of Chronic Obstructive Pulmonary Disease (COPD) study, we applied the MaRR procedure after data processing to explore reproducibility across technical or biological samples. Under realistic settings of MS-Metabolomics data, the MaRR procedure effectively controls the False Discovery Rate (FDR) when there was a gradual reduction in correlation between replicate pairs for less highly ranked signals. Simulation studies also show that the MaRR procedure tends to have high power for detecting reproducible metabolites in most situations except for smaller values of proportion of reproducible metabolites. Bias (i.e., the difference between the estimated and the true value of reproducible signal proportions) values for simulations are also close to zero. The results reported from the real data show a higher level of reproducibility for technical replicates compared to biological replicates across all the three different datasets. In summary, we demonstrate that the MaRR procedure application can be adapted to various experimental designs, and that the nonparametric approach performs consistently well. CONCLUSIONS: This research was motivated by reproducibility, which has proven to be a major obstacle in the use of genomic findings to advance clinical practice. In this paper, we developed a data-driven approach to assess the reproducibility of MS-Metabolomics data sets. The methods described in this paper are implemented in the open-source R package marr, which is freely available from Bioconductor at http://bioconductor.org/packages/marr .


Assuntos
Metabolômica , Espectrometria de Massas , Reprodutibilidade dos Testes
2.
Mol Med Rep ; 24(3)2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34296286

RESUMO

Renal tubular epithelial cell injury is the main cause of septic acute kidney injury (AKI), which is characterized by the excessive inflammatory response and apoptosis. Numerous studies have demonstrated that miRNAs are associated with inflammatory response and apoptosis in numerous diseases. The present study mainly focuses on investigating the association between microRNA (miRNA/miR) expression and inflammatory response and apoptosis in the pathogenesis of AKI. In vitro and in vivo models of AKI were simulated using Escherichia coli lipopolysaccharide (LPS)­administrated kidney epithelial cells and mice, respectively. The miRNA expression profile was examined using miRNA microarray in kidney tissues. Next, the effects of miR­93 upregulation on the apoptosis, cytokine expression and oxidative stress in the LPS­stimulated TCMK­1 were tested. The target genes of this miRNA were investigated, and the regulatory association between miR­93 and the AKT/mTOR pathway was investigated. The results demonstrated that miR­93 was the most downregulated miRNA in mice kidney. Furthermore, in LPS­induced renal tubular epithelial cells (TECs) injury model, that upregulation of miR­93 was found to attenuate the apoptosis and inflammatory response, as well as reactive oxygen species generation. Mechanistically, phosphatase and tensin homolog deleted on chromosome 10 (PTEN) was identified as a target of miR­93. Further experiments revealed that LPS­induced the decrease of phosphorylated (p)­AKT and p­mTOR protein expression in vitro are reversed by the overexpression of miR­93. The results of the present study suggested that the protective effect of miR­93 on AKI may be associated with the activation of PTEN/AKT/mTOR pathway. miR­93 may serve as a potential therapeutic target in sepsis­induced AKI.

3.
Sci Total Environ ; 797: 149181, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34311379

RESUMO

Low-cost gravity-driven membrane (GDM) filtration has the potential to efficiently manage highly decentralized shale gas wastewater (SGW). In this work, the feasibility of combining low dosage pre-ozonation with the GDM process was evaluated in the treatment of SGW. The results showed that pre-ozonation significantly increased the stable flux (372%) of GDM filtration, while slightly deteriorating the quality of the effluent water in terms of organic content (-14%). These results were mainly attributed to the conversion of macromolecular organics to low-molecular weight fractions by pre-ozonation. Interestingly, pre-ozonation markedly increased the flux (198%) in the first month of operation also for a GDM process added with granular activated carbon (GGDM). Nevertheless, the flux of O3-GGDM systems dropped sharply around the 25th day of operation, which might be due to the rapid accumulation of pollutants in the high flux stage and the formation of a dense fouling layer. Pre-ozonation remarkably influenced the microbial community structure. And O3-GDM systems were characterized by distinct core microorganisms, which might degrade specific organics in SGW. Furthermore, O3-GDM outperformed simple GDM as a pretreatment for RO. These findings can provide valuable references for combining oxidation technologies with the GDM process in treating refractory wastewater.


Assuntos
Ozônio , Purificação da Água , Filtração , Membranas Artificiais , Gás Natural , Águas Residuárias
4.
Aging (Albany NY) ; 13(12): 16072-16087, 2021 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-34120890

RESUMO

Hepatocellular carcinoma (HCC) serves as a prevailing global malignancy with severe mortality and extremely unsatisfactory prognosis, in which autophagy is a fundamental process in liver cancer pathogenesis, but the mechanisms are poorly understood. MicroRNAs (miRNAs) serve as a type of well-recognized non-coding regulators and contribute to the modulation of liver cancer development, from the aspects of diagnosis, progression, and therapy. Here, we aimed to investigate the function of hsa_microRNA-513b-5p (miR-513b-5p) in regulating autophagy during HCC progression. Specifically, our data showed that miR-513b-5p mimic reduced the LC3-II and beclin1 expression but enhanced p62 expression in HCC cells. MiR-513b-5p repressed liver cancer cell proliferation, migration/invasion, and induced apoptosis in vitro. Crucially, miR-513b-5p attenuated tumor growth of liver cancer cells in vivo. In the mechanical investigation, we identified that PIK3R3 mRNA 3'UTR was targeted by miR-513b-5p and miR-513b-5p suppressed PIK3R3 expression. PIK3R3 overexpression partly reversed miR-513b-5p-mediated autophagy, proliferation, and apoptosis of liver cancer cells. Consequently, we concluded that miR-513b-5p repressed autophagy during the malignant progression of HCC by targeting PIK3R3. MiR-513b-5p may be applied as a therapeutic target for HCC.


Assuntos
Autofagia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Progressão da Doença , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Adenina/análogos & derivados , Adenina/farmacologia , Apoptose/genética , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Humanos , MicroRNAs/genética , Invasividade Neoplásica
5.
Hemodial Int ; 25(4): E33-E39, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34121321

RESUMO

BACKGROUND: Many studies have shown that compared with those who use other dialysis modalities, patients using home hemodialysis (HHD) have an increased rate of survival and better quality of life. It was noted in 2006 that there was opportunity for significant expansion of the use of HHD in many countries. China covers a vast area and has a large amount of end-stage renal failure patients. But in mainland China, all dialysis treatments are in-center, and the number of HHD patients is zero. In 2018, our hospital received the permission of the Shanghai government to carry out HHD. CASE PRESENTATION: We initiated four incident hemodialysis patients on an HHD regimen, one patient has been dialyzed in the home safely for 8 months. The biochemical parameters of the first patient remained stable on the regimen and he achieved standard Kt/V urea targets. Treatment-related adverse events were not reported during the follow-up. We combined HHD with intelligent "Internet Plus" real-time remote monitoring and introduced the Internet, especially visualization software, to replace traditional telephone and home visit methods. It is more intuitive and quicker to assist patients in performing home hemodialysis and improve the safety of treatment. CONCLUSIONS: HHD can be performed by selected trained patients in mainland China. Combined with the internet, visualization software, and traditional telephone and home visits, it is intuitive and quick to assist patients in carrying out HHD and improve the safety of treatment. HHD broadens the choices for uremia patients in China.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34115588

RESUMO

Invertible grayscale is a special kind of grayscale from which the original color can be recovered. Given an input color image, this seminal work tries to hide the color information into its grayscale counterpart while making it hard to recognize any anomalies. This powerful functionality is enabled by training a hiding sub-network and restoring sub-network in an end-to-end way. Despite its expressive results, two key limitations exist: 1) The restored color image often suffers from some noticeable visual artifacts in the smooth regions. 2) It is very sensitive to JPEG compression, i.e., the original color information cannot be well recovered once the intermediate grayscale image is compressed by JPEG. To overcome these two limitations, this paper introduces adversarial training and JPEG simulator respectively. Specifically, two auxiliary adversarial networks are incorporated to make the intermediate grayscale images and final restored color images indistinguishable from normal grayscale and color images. And the JPEG simulator is utilized to simulate real JPEG compression during the online training so that the hiding and restoring sub-networks can automatically learn to be JPEG robust. Extensive experiments demonstrate that the proposed method is superior to the original invertible grayscale work both qualitatively and quantitatively while ensuring the JPEG robustness. We further show that the proposed framework can be applied under different types of grayscale constraints and achieve excellent results.

7.
Sci Total Environ ; 773: 144564, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33940700

RESUMO

Albic soil is a low-yielding soil that is widely distributed in Northeast China. The high viscosity and acidity and the lack of nutrients in the Albic layer limit the growth of crop. In our previous studies, we found that applying biochar as a soil amendment could improve the properties of Albic soil and promote soybean growth. Increases in the nitrogen contents of the soil and the soybeans were key aspects of these improvements. Soybean is a nitrogen-fixing crop, the increase in nitrogen in the Albic soil may have been due to an improvement in biological nitrogen fixation by the soybean with biochar amendment, but the function mechanism was still uncertain. We hypothesized that biochar could improve biological nitrogen fixation of soybean by affecting soybean root growth in the Albic soil. Therefore, we conducted pot experiments with five treatment levels (0, 10, 20, 30, and 40 g·kg-1 biochar) for two years to study how biochar affects the root growth strategy and biological nitrogen fixation of soybean based on its root structure and root nutrient acquisition ability at different stages. The soybean root structure and activity indexes, nodulation ability and nitrogen uptake were measured at different growth stages; in the second year, at the late seed-filling stage, the stable 15N isotope method was used to elucidate the biological nitrogen fixation process. Regarding root structure at the pod-setting stage, biochar resulted in increases in root length density, specific root length, root diameter and specific tip density but a decrease in root tissue mass density at the pod-setting stage. Biochar improved root nutrient acquisition by increasing root activity, root tip number and root-bleeding sap amount. The change in root growth strategy contributed to the promotion of biological nitrogen fixation by the rhizobia that live symbiotically with soybean, thereby increasing crop yield.


Assuntos
Solo , Soja , Carvão Vegetal , China , Fixação de Nitrogênio
8.
Artigo em Inglês | MEDLINE | ID: mdl-33973777

RESUMO

Adsorption as a desalination approach has the advantages of energy efficiency, low cost, and operational convenience, but its practical application is limited by low desalination capacity, consumption/disposal of strong acids/bases as regeneration reagents, and poor reusability. Herein, we synthesized a thermo-regenerable salt absorbent by grafting ethylenediaminetetraacetic acid (EDTA) onto a metal-organic framework (MOF), MOF-808-EDTA, which could rapidly adsorb NaCl within 30 min from saline water at 25 °C with a desalination capacity as high as 9.4 mmol/g. Moreover, the saturated adsorbent could be facilely regenerated in 80 °C water. Fourier transform infrared spectroscopy and derivative thermogravimetry revealed that temperature-regulated proton transfer between amino and carboxyl groups was the mechanism of thermo-regeneration. EDTA on MOF-808-EDTA appears in a zwitterionic state in water at room temperature, which allowed simultaneous adsorption of Na+ and Cl-. At elevated temperature, it returned to a nonionic state accompanied by the desorption of ions. A similar temperature-dependent adsorption-regeneration process was also observed for other salts, including LiCl, KCl, CaCl2, and MgCl2. Column experiments of brackish groundwater showed that 1 g of MOF-808-EDTA could produce ∼106 mL of fresh water (total dissolved solids < 600 mg/L) without significant capacity loss after 10 successive adsorption-regeneration cycles. This study is the first to propose an EDTA-based MOF for desalination and indicates the potential of MOF-808-EDTA as a green adsorbent for sustainable water desalination.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33886472

RESUMO

Three-dimensional (3-D) meshes are commonly used to represent virtual surfaces and volumes. Over the past decade, 3-D meshes have emerged in industrial, medical, and entertainment applications, being of large practical significance for 3-D mesh steganography and steganalysis. In this article, we provide a systematic survey of the literature on 3-D mesh steganography and steganalysis. Compared with an earlier survey [1], we propose a new taxonomy of steganographic algorithms with four categories: 1) two-state domain, 2) LSB domain, 3) permutation domain, and 4) transform domain. Regarding steganalysis algorithms, we divide them into two categories: 1) universal steganalysis and 2) specific steganalysis. For each category, the history of technical developments and the current technological level are introduced and discussed. Finally, we highlight some promising future research directions and challenges in improving the performance of 3-D mesh steganography and steganalysis.

10.
Pharmacol Res ; 167: 105531, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33675964

RESUMO

Contrast-induced acute kidney injury (CI-AKI) is a main cause of hospital-acquired renal failure. Nevertheless, limited measures have been shown to be effective for the treatment of CI-AKI. Here, we demonstrated that αKlotho, which is highly expressed in kidney, has therapeutic activity in CI-AKI. Our data showed that αKlotho expression levels were decreased both in the kidney and serum of CI-AKI mice. Administration of αKlotho protein protected the kidney and HK-2 cells against contrast-induced injury. Mechanistically, αKlotho reduced contrast-induced renal tubular cells pyroptosis by limiting NLRP3 inflammasome activation. Meanwhile, αKlotho up-regulated autophagy via inhibiting the AKT/mTOR pathway and decreased mitochondrial ROS level. Inhibition of autophagy blunted the suppression effect of αKlotho on NLRP3 inflammasome activation and cell pyroptosis in contrast-treated HK-2 cells. Taken together, our data suggest that αKlotho protein protects against CI-AKI through inhibiting NLRP3 inflammasome-mediated pyroptosis, which is likely by promoting autophagy. αKlotho may be a promising therapeutic strategy for CI-AKI.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33687836

RESUMO

Despite the tremendous success, deep neural networks are exposed to serious IP infringement risks. Given a target deep model, if the attacker knows its full information, it can be easily stolen by fine-tuning. Even if only its output is accessible, a surrogate model can be trained through student-teacher learning by generating many input-output training pairs. Therefore, deep model IP protection is important and necessary. However, it is still seriously under-researched. In this work, we propose a new model watermarking framework for protecting deep networks trained for low-level computer vision or image processing tasks. Specifically, a special task-agnostic barrier is added after the target model, which embeds a unified and invisible watermark into its outputs. When the attacker trains one surrogate model by using the input-output pairs of the barrier target model, the hidden watermark will be learned and extracted afterwards. To enable watermarks from binary bits to high-resolution images, a deep invisible watermarking mechanism is designed. By jointly training the target model and watermark embedding, the extra barrier can even be absorbed into the target model. Through extensive experiments, we demonstrate the robustness of the proposed framework, which can resist attacks with different network structures and objective functions.

12.
Medicine (Baltimore) ; 100(12): e25017, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33761657

RESUMO

ABSTRACT: Overweight and obesity may be associated with poor clinical outcome, including chronic kidney disease (CKD). However, whether body mass index (BMI), waist-to-hip ratio (WHR), and waist circumference (WC) are related to CKD is yet to be elucidated.A total of 7593 adults were divided into 4 groups based on the estimated glomerular filtration rate (eGFR) quartile. The eGFR was calculated with the CKD Epidemiology Collaboration. Multiple linear regression analyzed the association between eGFR and WHR, BMI, and WC. Logistic regression analysis determined whether the CKD patients were associated with WHR, BMI, and WC after adjusting for other variables.The mean age of the cohort was 72.34 ±â€Š7.30 years. Multiple linear regression analysis showed that WC (P = .006) was associated with eGFR, although adjusted by lifestyle factor and biochemical indicators. The individuals in the underweight, overweight, and obese groups had significantly lower eGFR value than those in the healthy weight group in moderate CKD. The eGFR in the overweight group with WHR ≤0.894 was higher than in the healthy weight group with WHR >0.894 group (P = .036). Overweight with WHR ≤0.894 group had a longer WC with a pronounced increase in the hip circumference. Logistic regression analysis showed that the WC (OR = 1.362, P < .001) and BMI (OR = 1.227, P = .031) were independent risk factors for moderate CKD patients. Each standard deviation (SD) of high BMI and WC level was associated with 23.0% and 17.3% higher odds of moderate CKD (OR = 1.230, P = .017 and OR = 1.173, P = .021, respectively).WC is an independent risk factor for eGFR. Combined BMI and WC are important factors that would predict moderate CKD patients.


Assuntos
Índice de Massa Corporal , Insuficiência Renal Crônica/diagnóstico , Circunferência da Cintura , Relação Cintura-Quadril , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Taxa de Filtração Glomerular , Humanos , Estilo de Vida , Modelos Logísticos , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Magreza/fisiopatologia , Adulto Jovem
13.
Sci Total Environ ; 762: 143083, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33162134

RESUMO

Multifunctional ultrafiltration membranes, which achieve ultrafiltration and additional functions in one unit, are a new strategy developed in recent years for wastewater treatment. In this mini review, we summarized and commented on the development of adsorptive and catalytically oxidative multifunctional ultrafiltration membranes, as well as pointed out possible further trends. The main methods for membrane preparation, i.e., blending, surface coating, reverse filtration, etc., were summarized, and the advantages and disadvantages of each method were discussed. In addition, the key criteria which influence the performance of membranes, including the efficiency of additional functions, original ultrafiltration, permeance, and stability, were analyzed. Furthermore, we introduced the applications of different classes of multifunctional ultrafiltration membranes, and tried to further analyzed some examples of multifunctional ultrafiltration membranes used for adsorption and catalytic oxidation. The most significant advantage of this technology is the high efficiency for the simultaneous removal of different kinds of pollutants or for the removal of one kind of pollutant during the deep treatment of multicomponent wastewater. However, some challenges still oppose the practical application of multifunctional ultrafiltration. We believe that breaking the trade-off between the high efficiency of additional functions and high flux, strengthening the stability of the membranes, achieving synergistic effects between multi-effect functions, and investigating the interaction mechanisms between active materials and the membrane are key points for further research.

14.
Water Res ; 189: 116599, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33166920

RESUMO

Adsorption is a viable technology to remove trace heavy metals from wastewater, but regeneration of adsorbents in an economic and environmentally friendly manner often represents a limiting factor of its application. Compared with traditional strong acid desorption, developing a chemical-free method is of great significance to both economic and the environmental welfare. Herein, we synthesized a novel thermoresponsive absorbent, A-MIL-121, which could effectively remove trace Cu(II) (> 95 %) from a high-salinity ([Na+]/[Cu2+] = 20000) water at normal temperature. At elevated temperature, A-MIL-121 could quickly and efficiently desorb Cu(II), with over 90% desorption rate at 80°C within 3 h. Fourier transform infrared spectroscopy (FTIR) analysis revealed that two types of -COOH groups existed in the material. One was in free form and acted as the sites for Cu(II) adsorption; the other was in dimer connected by two H-bonds, which cleaved at elevated temperature. As a result, massive exchangeable protons were released to the solution, which caused the desorption of Cu(II). Similar temperature dependent adsorption-desorption behavior was also found to other heavy metals, such as Cd2+, Pb2+, Ni2+. No significant capacity loss was observed after 10 successive adsorption-desorption cycles. Finally, Column experiments using a real copper electroplating wastewater showed that a total of ~ 1650 mL of clean water was generated before breakthrough (Cu2+ < 0.5 mg/L), while less than 45 mL of 80°C water was used for regeneration. This study indicates the potential of A-MIL-121 as a novel green adsorbent to address trace heavy metals in wastewater.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Adsorção , Compostos de Alumínio , Concentração de Íons de Hidrogênio , Cinética , Prótons , Temperatura , Poluentes Químicos da Água/análise
15.
Chemosphere ; 263: 127938, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32829222

RESUMO

The urgent need for eutrophication control motivated the development of many novel adsorbents for enhanced phosphate polishing removal. Among these, zirconium-based nanomaterial was regarded as an effective kind because of its ability to bind phosphate specifically via inner-sphere complexation. In this study, we proposed a new strategy to improve the efficiency of zirconium oxides (HZO) nanoparticles by immobilizing them onto a gel-type anion exchange resin covalently attached with ammonium groups, denoted as HZO@N201. A previously developed macro-porous polymeric nanocomposite HZO@D201 was used for comparison. The immobilized nanoparticles in HZO@N201 were well dispersed in the gel matrix, manifesting smaller particle size and richer surface hydroxyl groups in comparison to HZO@D201. As a result of the structural merits in collective, HZO@N201 not only exhibited superior phosphate adsorptive capacity and affinity towards phosphate to HZO@D201, but also facilitate phosphate diffusion, based on isotherm, pH and kinetic tests. Mechanistic study by XPS and 31P SS-NMR substantiated the selective phosphate adsorption pathway as the formation of inner-sphere complexes by HZO@N201, which exhibited enhanced reactivity than HZO@D201. Lastly, fixed-bed runs of HZO@N201 was conducted, achieving an effective treatable volume of 2000 BV, which was 600 BV more than HZO@D201. Additional adsorption-regeneration cycle confirmed its reusability and potential for practical application. We believe the gel-type polymeric host could facilitate the formation and dispersion of smaller sized nanoparticles, exposing more surface hydroxyl groups highly accessible to phosphate. The results of this paper offer insights to a new strategy for immobilization of functional nanoparticles aiming at enhanced adsorptive removal of phosphate.


Assuntos
Fosfatos/química , Poliestirenos/química , Poluentes Químicos da Água/química , Zircônio/química , Adsorção , Resinas de Troca Aniônica/química , Concentração de Íons de Hidrogênio , Imobilização , Nanocompostos/química , Nanopartículas , Óxidos , Polímeros , Poluentes Químicos da Água/análise
16.
J Hazard Mater ; 402: 123766, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33254778

RESUMO

Fenton-like oxidation for multicomponent wastewater treatment suffers from a low efficiency due to non-selective nature of produced reactive species. In this study, a multifunctional dual-layer ultrafiltration membrane (Seq-ICM) was synthesized for multiple pollutants decontamination. Characterizations of the membranes indicate that Seq-ICM comprises a skin layer for ultrafiltration, and a porous support layer loaded with ∼50% MIL-53(Fe) for catalysis. With bovine serum albumin coexisting, Seq-ICM can remove 75.7% bisphenol S (BPS), which is much higher than that of a simultaneous interception-catalysis membrane (44.2 %). For multicomponent wastewater treatment, Seq-ICM system can save ∼59%-67% oxidant dosage as well compared with catalysis alone membrane system to achieve 50% BPS removal. Furthermore, the decontamination mechanisms were investigated to explain the advantages of Seq-ICM. Sequential interception and oxidation process by Seq-ICM leads to the interception of macromolecular substances first, following by catalytic oxidation of low-molecular-weight organics. This process prevents macromolecular substances from competing for active species with low-molecular-weight organics, thereby enhancing selectivity and oxidation efficiency. Meanwhile, Seq-ICM shows satisfactory BPS removal efficiency for treatment of 2865 L/m2 synthetic solution, as well as in real wastewater matrix. We believe the proposed technology based on a composite membrane is promising for the removal of multicomponent substances from wastewater.

17.
Entropy (Basel) ; 22(8)2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33286663

RESUMO

Stealth malware is a representative tool of advanced persistent threat (APT) attacks, which poses an increased threat to cyber-physical systems (CPS) today. Due to the use of stealthy and evasive techniques, stealth malwares usually render conventional heavy-weight countermeasures inapplicable. Light-weight countermeasures, on the other hand, can help retard the spread of stealth malwares, but the ensuing side effects might violate the primary safety requirement of CPS. Hence, defenders need to find a balance between the gain and loss of deploying light-weight countermeasures, which normally is a challenging task. To address this challenge, we model the persistent anti-malware process as a shortest-path tree interdiction (SPTI) Stackelberg game with both static version (SSPTI) and multi-stage dynamic version (DSPTI), and safety requirements of CPS are introduced as constraints in the defender's decision model. The attacker aims to stealthily penetrate the CPS at the lowest cost (e.g., time, effort) by selecting optimal network links to spread, while the defender aims to retard the malware epidemic as much as possible. Both games are modeled as bi-level integer programs and proved to be NP-hard. We then develop a Benders decomposition algorithm to achieve the Stackelberg equilibrium of SSPTI, and design a Model Predictive Control strategy to solve DSPTI approximately by sequentially solving an 1+δ approximation of SSPTI. Extensive experiments have been conducted by comparing proposed algorithms and strategies with existing ones on both static and dynamic performance metrics. The evaluation results demonstrate the efficiency of proposed algorithms and strategies on both simulated and real-case-based CPS networks. Furthermore, the proposed dynamic defense framework shows its advantage of achieving a balance between fail-secure ability and fail-safe ability while retarding the stealth malware propagation in CPS.

18.
Sci Rep ; 10(1): 21582, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33299113

RESUMO

A pot experiment was used to explore the distribution of fertilizer N and agronomic effects in a paddy soil-rice (Oryza sativa L.) system. Five treatments were set: without nitrogen, straw and inhibitor (C), urea (U), urea + straw (US), urea + urease + nitrification inhibitor (UI) and urea + urease + nitrification inhibitor + straw (UIS). Soil and urea-derived microbial biomass N increased significantly in US and UIS compared with straw-free treatments at seedling and tillering, indicating that biotic process play an important role in the retention of fertilizer N with straw addition. About 10% urea-N was recovered as fixed ammonium (FA) at seedling stage, subsequently released at tillering and maturation regardless of treatments, which emphasizes the importance of FA in the retention and supply of fertilizer N in paddy soils. Compared with U, rice yield and N uptake in US decreased by 7.8% and 25.2% respectively, while inhibitors (UIS) alleviated the reduction by 16.4% and 31.6%. The current research indicated UIS is recommended as the most appropriate management strategy in paddy soils of Northeast China based on N dynamics. But the economic effect as well as the field-scale validation need to be further evaluated.

19.
Huan Jing Ke Xue ; 41(12): 5500-5508, 2020 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-33374066

RESUMO

Pharmaceuticals and personal care products (PPCPs) adsorption and membrane fouling control were realized by a polyvinylidene fluoride (PVDF) membrane loaded with multifunctional metal-organic frameworks (MOFs) in this study. During adsorption, the multifunctional MOFs UiO-66@Fe3O4@UiO-66 in the mixed-matrix membrane (MMMs) could adsorb two typical PPCPs, salicylic acid (SA), and dimethyl phthalate (DMP), efficiently. In the membrane catalytic regeneration process, Fe3O4 in UiO-66@Fe3O4@UiO-66 could catalyze H2O2 to generate hydroxyl radicals (HO·), coupling MOFs/PVDF adsorption capacity regeneration and membrane cleaning. The results show that 10%MOFs/PVDF exhibits the highest adsorption efficiency for 0.1 mmol·L-1 SA and DMP under neutral conditions, and the removal rate reached 64.2% and 46.1%, respectively. Additionally, the pure water flux and membrane adsorption capacity of 10%MOFs/PVDF were able to recover about 91.8% and 94.2%, respectively, using 5 mmol·L-1 H2O2. In this research, the main characteristic of MOFs/PVDF is coupling of the membrane adsorption capacity regeneration and membrane fouling control process. This provides new ideas for the removal of PPCPs and the improvement of membrane anti-fouling performance during the deep purification of secondary effluent.

20.
Environ Health Perspect ; 128(12): 127014, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33356526

RESUMO

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are environmentally persistent chemicals widely detected in women of reproductive age. Prenatal PFAS exposure is associated with adverse health outcomes in children. We hypothesized that DNA methylation changes may result from prenatal PFAS exposure and may be linked to offspring cardio-metabolic phenotype. OBJECTIVES: We estimated associations of prenatal PFAS with DNA methylation in umbilical cord blood. We evaluated associations of methylation at selected sites with neonatal cardio-metabolic indicators. METHODS: Among 583 mother-infant pairs in a prospective cohort, five PFAS were quantified in maternal serum (median 27 wk of gestation). Umbilical cord blood DNA methylation was evaluated using the Illumina HumanMethylation450 array. Differentially methylated positions (DMPs) were evaluated at a false discovery rate (FDR)<0.05 and differentially methylated regions (DMRs) were identified using comb-p (Sidák-adjusted p<0.05). We estimated associations between methylation at candidate DMPs and DMR sites and the following outcomes: newborn weight, adiposity, and cord blood glucose, insulin, lipids, and leptin. RESULTS: Maternal serum PFAS concentrations were below the median for females in the U.S. general population. Moderate to high pairwise correlations were observed between PFAS concentrations (ρ=0.28-0.76). Methylation at one DMP (cg18587484), annotated to the gene TJAP1, was associated with perfluorooctanoate (PFOA) at FDR< 0.05. Comb-p detected between 4 and 15 DMRs for each PFAS. Associated genes, some common across multiple PFAS, were implicated in growth (RPTOR), lipid homeostasis (PON1, PON3, CIDEB, NR1H2), inflammation and immune activity (RASL11B, RNF39), among other functions. There was suggestive evidence that two PFAS-associated loci (cg09093485, cg09637273) were associated with cord blood triglycerides and birth weight, respectively (FDR< 0.1). DISCUSSION: DNA methylation in umbilical cord blood was associated with maternal serum PFAS concentrations during pregnancy, suggesting potential associations with offspring growth, metabolism, and immune function. Future research should explore whether DNA methylation changes mediate associations between prenatal PFAS exposures and child health outcomes. https://doi.org/10.1289/EHP6888.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Fluorcarbonetos/sangue , Biomarcadores/sangue , Metilação de DNA , Sangue Fetal/metabolismo , Humanos , Recém-Nascido
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