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1.
Nat Methods ; 20(3): 459-468, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36823335

RESUMO

Single-molecule localization microscopy in a typical wide-field setup has been widely used for investigating subcellular structures with super resolution; however, field-dependent aberrations restrict the field of view (FOV) to only tens of micrometers. Here, we present a deep-learning method for precise localization of spatially variant point emitters (FD-DeepLoc) over a large FOV covering the full chip of a modern sCMOS camera. Using a graphic processing unit-based vectorial point spread function (PSF) fitter, we can fast and accurately model the spatially variant PSF of a high numerical aperture objective in the entire FOV. Combined with deformable mirror-based optimal PSF engineering, we demonstrate high-accuracy three-dimensional single-molecule localization microscopy over a volume of ~180 × 180 × 5 µm3, allowing us to image mitochondria and nuclear pore complexes in entire cells in a single imaging cycle without hardware scanning; a 100-fold increase in throughput compared to the state of the art.


Assuntos
Aprendizado Profundo , Imageamento Tridimensional/métodos , Imagem Individual de Molécula/métodos
2.
Opt Lett ; 49(10): 2785-2788, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748161

RESUMO

Single-molecule localization microscopy (SMLM) enables three-dimensional (3D) super-resolution imaging of nanoscale structures within biological samples. However, prolonged acquisition introduces a drift between the sample and the imaging system, resulting in artifacts in the reconstructed super-resolution image. Here, we present a novel, to our knowledge, 3D drift correction method that utilizes both the reflected and scattered light from the sample. Our method employs the reflected light of a near-infrared (NIR) laser for focus stabilization while synchronously capturing speckle images to estimate the lateral drift. This approach combines high-precision active compensation in the axial direction with lateral post-processing compensation, achieving the abilities of 3D drift correction with a single laser light. Compared to the popular localization events-based cross correlation method, our approach is much more robust, especially for datasets with sparse localization points.

3.
Mol Cell Biochem ; 479(3): 653-664, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37155089

RESUMO

Pleckstrin homeolike domain, family A, member 1 (PHLDA1) is a multifunctional protein that plays diverse roles in A variety of biological processes, including cell death, and hence its altered expression has been found in different types of cancer. Although studies have shown a regulatory relationship between p53 and PHLDA1, the molecular mechanism is still unclear. Especially, the role of PHLDA1 in the process of apoptosis is still controversial. In this study, we found that the expression of PHLDA1 in human cervical cancer cell lines was correlated with the up-expression of p53 after treatment with apoptosis-inducing factors. Subsequently, the binding site and the binding effect of p53 on the promoter region of PHLDA1 were verified by our bioinformatics data analysis and luciferase reporter assay. Indeed, we used CRISPR-Cas9 to knockout the p53 gene in HeLa cells and further confirmed that p53 can bind to the promoter region of PHLDA1 gene, and then directly regulate the expression of PHLDA1 by recruiting P300 and CBP to change the acetylation and methylation levels in the promoter region. Finally, a series of gain-of-function experiments further confirmed that p53 re-expression in HeLap53-/- cell can up-regulate the reduction of PHLDA1 caused by p53 knockout, and affect cell apoptosis and proliferation. Our study is the first to explore the regulatory mechanism of p53 on PHLDA1 by using the p53 gene knockout cell model, which further proves that PHLDA1 is a target-gene in p53-mediated apoptosis, and reveals the important role of PHLDA1 in cell fate determination.


Assuntos
Fatores de Transcrição , Proteína Supressora de Tumor p53 , Humanos , Apoptose , Células HeLa , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética
4.
Phys Chem Chem Phys ; 26(26): 18006-18015, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38894605

RESUMO

In recent years, all-inorganic perovskites CsPbX3 (X = Cl, Br, I) have emerged as excellent candidates for solar cells due to their remarkable thermal stability and suitable bandgaps. Among them, CsPbI2Br is a hotspot in perovskite material research currently. Non-radiative electron-hole recombination often leads to significant energy losses, impacting the efficiency of solar cells, so a thorough understanding of carrier recombination mechanisms is crucial. Our work investigated the carrier recombination dynamics in detail and proved that strains can effectively reduce nonradiative recombination. In this study, using first-principles calculations combined with nonadiabatic (NA) molecular dynamics (MD), we demonstrate that applying 2% tensile and 2% compressive strains to CsPbI2Br can modify the bandgap, induce moderate disorder, reduce the overlap of electron-hole wavefunctions, decrease NA coupling, and shorten decoherence time, thereby minimizing non-radiative recombination and extending the carrier lifetime. Especially the 2% tensile strain exhibits more effective control performance, significantly reducing non-radiative electron-hole recombination and extending the charge carrier lifetime to 14.59 ns, nearly five times that of the pristine CsPbI2Br system (3.12 ns). This study reveals the impact mechanism of strain on carrier behavior in perovskite solar cells, providing a new non-chemical strategy for modulating the lifetime of photo-generated carriers and enhancing the efficiency of all-inorganic perovskite solar cells.

5.
BMC Pulm Med ; 24(1): 277, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862955

RESUMO

BACKGROUND: We aimed to determine whether systemic immune-inflammation index (SII) combined with prealbumin can provide better predictive power for postoperative pneumonia in patients undergoing lung resection surgery. METHODS: We identified eligible patients undergoing lung resection surgery at the Affiliated Hospital of Nantong University from March 2021 to March 2022. Demographic characteristics, clinical data, and laboratory information were collected and reviewed from the electronic medical records of the patients. To test the effect of the combined detection of SII and prealbumin, we made an equation using logistic regression analysis. The receiver operating characteristic curve (ROC) was plotted to evaluate the predictive powers, sensitivity, and specificity of prealbumin, SII, and SII combined with prealbumin. Decision curve analysis (DCA) was used to determine the clinical validity and net benefit of different methods of detection. RESULTS: Totally 386 eligible patients were included with a median age of 62.0 years (IQR: 55.0, 68.0), and 57 (14.8%) patients presented with postoperative pneumonia within 7 days after surgery. The multivariate regression analysis showed that preoperative SII as continuous variable was associated with an increased risk of postoperative pneumonia (OR: 1.38, 95% CI: 1.19-2.83, P = 0.011), whereas the prealbumin as continuous variable remained as an independent protective predictor of postoperative pneumonia in the adjusted analysis (OR: 0.80, 95% CI: 0.37-0.89, P = 0.023). Compared to SII or prealbumin, the combined detection of preoperative SII and prealbumin showed a higher predictive power with area under curve of 0.79 (95% CI: 0.71-0.86, P < 0.05 for all). Additionally, DCA indicated that the combined detection was superior over preoperative SII or prealbumin alone in clinical validity and net benefit. CONCLUSION: Both preoperative SII and prealbumin are independent influencing factors for postoperative pneumonia after lung resection surgery. The combined detection of preoperative SII and prealbumin can significantly improve prediction capability to identify potential postoperative pneumonia-susceptible patients, facilitating early interventions to improve postoperative quality of life for surgical lung resection patients.


Assuntos
Pneumonia , Complicações Pós-Operatórias , Pré-Albumina , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Pneumonia/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Idoso , Pré-Albumina/análise , Pré-Albumina/metabolismo , Estudos Retrospectivos , Pneumonectomia/efeitos adversos , Valor Preditivo dos Testes , Curva ROC , Modelos Logísticos , Inflamação
6.
J Am Chem Soc ; 145(4): 2252-2263, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36657461

RESUMO

It is highly desirable to fabricate an accessible catalyst surface that can efficiently activate reactants and desorb products to promote the local surface reaction equilibrium in heterogeneous catalysis. Herein, rare-earth oxycarbonates (Ln2O2CO3, where Ln = La and Sm), which have molecular-exchangeable (H2O and CO2) surface structures according to the ordered layered arrangement of Ln2O22+ and CO32- ions, are unearthed. On this basis, a series of Ln2O2CO3-supported Cu catalysts are prepared through the deposition precipitation method, which provides excellent catalytic activity and stability for the water-gas shift (WGS) reaction. Density functional theory calculations combined with systematic experimental characterizations verify that H2O spontaneously dissociates on the surface of Ln2O2CO3 to form hydroxyl by eliminating the carbonate through the release of CO2. This interchange efficiently promotes the WGS reaction equilibrium shift on the local surface and prevents the carbonate accumulation from hindering the active sites. The discovery of the unique layered structure provides a so-called "self-cleaning" active surface for the WGS reaction and opens new perspectives about the application of rare-earth oxycarbonate nanomaterials in C1 chemistry.

7.
Sensors (Basel) ; 23(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37836905

RESUMO

With the progression of marine exploration and exploitation, as well as the advancements in mechanical intelligence, the utilization of the unmanned surface vehicle (USV) and the design of their guidance system have become prominent areas of focus. However, the stern ramp recovery of the USV is still in its infancy due to its unique attitude requirements and automation design. Furthermore, few studies have addressed the impact of maritime disturbances, with most research limited to simulations. To enhance the efficiency and accuracy of stern ramp recovery, this paper presents the development and construction of a novel recovery system. By incorporating physical modeling of disturbance forces acting on USVs at sea, the practicality of the system is improved. Additionally, an optimized genetic algorithm is introduced in the navigation module to improve convergence rates and subsequently enhance recovery efficiency. A line-of-sight (LOS) algorithm based on average velocity is proposed in this paper to ensure the attainment of unique attitude requirements and to improve the effectiveness of stern chute recovery. This paper provides a detailed description of the independently designed USV hardware system. Moreover, simulations and practical experiments conducted using this experimental platform are presented, offering a new solution for the USV's stern ramp recovery.

8.
Opt Lett ; 47(12): 3031-3034, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35709042

RESUMO

Point spread function (PSF) engineering is an important technique to encode the properties (e.g., 3D positions, color, and orientation) of a single molecule in the shape of the PSF, often with the help of a programmable phase modulator. A deformable mirror (DM) is currently the most widely used phase modulator for fluorescence detection as it shows negligible photon loss. However, it relies on careful calibration for precise wavefront control. Therefore, design of an optimal PSF not only relies on the theoretical calculation of the maximum information content, but also the physical behavior of the phase modulator, which is often ignored during the optimization process. Here, we develop a framework for PSF engineering which could generate a device specific optimal PSF for 3D super-resolution imaging using a DM. We use our method to generate two types of PSFs with depths of field comparable to the widely used astigmatism and tetrapod PSFs, respectively. We demonstrate the superior performance of the DM specific optimal PSF over the conventional astigmatism and tetrapod PSF both theoretically and experimentally.


Assuntos
Astigmatismo , Calibragem , Humanos , Imageamento Tridimensional/métodos , Nanotecnologia , Fótons
9.
Endocr Pract ; 28(11): 1132-1139, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36126886

RESUMO

OBJECTIVE: Using claims data from an integrated payer-provider, we compared costs incurred by patients with insulin-dependent diabetes mellitus (IDDM) who received Hospital Inpatient/Observation/EmeRgency Department care (HIghER care) for diabetes-related events with those who did not receive such care to identify a target population for interventions in future studies. METHODS: A retrospective study pooled real-world claims data for IDDM (type 1 or type 2) between July 1, 2018, and June 30, 2019. Medical claims were used to calculate the total and diabetes-related allowed medical costs to the enterprise and per member per month costs. RESULTS: Medical and prescription drug coverage from 19 378 members was analyzed. Only 8.4% of the IDDM population received HIghER care but incurred 20% of medical expenses and nearly 40% of diabetes-related medical costs. For HIghER care patients, medical spending was higher in every inpatient and outpatient category (Wilcoxon 2-sample tests, all P < .0001). Non-diabetes-related prescription drug costs were greater in this group (Wilcoxon test, Z = 2.2879, P = .0221), whereas diabetes-related prescription drug costs were higher for non-HIghER care (Wilcoxon test, Z = -9.5918, P < .0001). In a longitudinal study of 29 602 patients over 24 months, previous-year receipt of HIghER care was a significant predictor of HIghER care the subsequent year (odds ratio, 3.28). CONCLUSION: Medical spending for patients receiving HIghER care was disproportionately high and greater in every inpatient and outpatient category. HIghER care receipt the previous year was highly predictive of HIghER care episodes the following year.


Assuntos
Diabetes Mellitus Tipo 1 , Insulinas , Medicamentos sob Prescrição , Humanos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Estudos Retrospectivos , Estudos Longitudinais , Hospitais , Custos de Cuidados de Saúde
10.
J Environ Manage ; 305: 114395, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34972049

RESUMO

Ultrasonication has been mechanically applied widely in the recycling of spent lithium-ion (SLI) batteries while its influence on chemical pathways has barely been reported. In this study, ultrasonication and sulfate radicals were used in a coupling system to obtain efficient recoveries of Co and Li from SLI batteries. The synergistic effect of ultrasonication and sulfate radicals on recycling was quantitatively analysed by significance analysis and surface responses in a central composite design. The employment of persulfate significantly affected the whole recycling process during the sonication. Factors including acoustic time, operating powers, and temperature all had a significant effect on the recoveries of Co and Li. The maximum recovery efficiencies of Co and Li of 97.33% and 99.25%, respectively, and the minimum loss rate of Al of 4.13% were simultaneously obtained by the fitting predictor. The optimal combination of factors for the sonication system included an acoustic time (min) of 5.5, an operating power (W) of 168, a temperature (°C) of 86, and a ratio of cathode foil to S-solution (mg/mL) of 1:60. A moiety of cathode active material was directly separated from the aluminium collector by sulfate radical-related reactions. Co and Li cations dissolved from LiCoO2 by carbon dioxide radicals were reprecipitated by excess oxalate. The research demonstrated the positively synergistic influence caused by ultrasonication and sulfate radicals on achieving efficient recoveries of Co and Li from SLI batteries, explicitly expanding the technical choices for the recycling procedure.


Assuntos
Cobalto , Lítio , Fontes de Energia Elétrica , Eletrodos , Reciclagem , Sulfatos
11.
J Environ Manage ; 324: 116344, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36166867

RESUMO

In this study, the 3-mercaptopropionic acid (MA) was chosen to achieve the anionic intercalation into the green rust (GR) materials (MA-GR). The zeolite-rich tuff functionalized with the MA-intercalated GR (MA-GR-tuff) was subsequently synthesized and used to remove both HgII cations and CrVI anions in a binary system. MA-GR-tuff showed the best adsorption capacities to both HgII and CrVI among the adsorbent materials. The optimal combination of parameters was determined as the molar ratio of FeII to FeIII of 3.5, the molar ratio of OH- to the total iron of 3.75, the molar ratio of MA to the total iron of 2.5, and the mass ratio of the total iron to the tuff of 1.25. The pseudo-first-order kinetic model was appropriate in describing the kinetic sorption of CrVI by MA-GR-tuff. Both the pseudo-first-order kinetic model and Elovich were suitable for explaining HgII sorption. The maximum monolayer adsorption capacities of MA-GR-tuff towards CrVI and HgII were 185.19 mg/g and 72.99 mg/g, respectively. More flocs and plumes were formed in the MA-GR while the intercalation and more pores and crevices of different sizes were found in the MA-GR-tuff. Sulfhydryl complexation and the molecular sieve of tuff obviously both played a role in influencing the adsorption process. This study directly overcomes the drawback brought by the natural tuff to the treatment of a cationic-and-anionic binary system and supplies a new kind of tuff-based adsorbent for the potential use for the remediation of HM-contaminated wastewater.


Assuntos
Mercúrio , Poluentes Químicos da Água , Zeolitas , Ácido 3-Mercaptopropiônico , Compostos Férricos , Concentração de Íons de Hidrogênio , Cromo/análise , Adsorção , Ferro , Cinética , Ânions , Cátions , Poluentes Químicos da Água/análise
12.
Small ; 17(13): e2007051, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33599061

RESUMO

Immune checkpoint inhibitor (ICI) therapy is considered to be a revolutionary anti-tumor strategy that may surpass other traditional therapies. Breast cancer is particularly suitable for it theoretically due to upregulation of programmed cell death 1 (PD-1) / programmed cell death ligand 1 (PD-L1) immune checkpoint pathway which exhausts the adaptive immune response mediated by T lymphocytes. However, its blockades exhibit very little effect in breast cancer, owing to the lack of T lymphocytes pre-infiltration and co-existing of intricate immune negative microenvironment including the macrophage-suppressed "Don't eat me" CD47 signal overexpression. Herein, a stimuli-responsive multifunctional nanoplatform (ZIF-PQ-PDA-AUN) is built. Its photothermal therapy can promote the infiltration of T lymphocytes in addition to ablating tumor cells and AUNP-12 and PQ912 further boost both the innate and adaptive immune reactions by cutting off PD-L1 and CD47 signals, respectively. In contrast to earlier single immunotherapy, the nanocomposites exhibit a stronger anti-tumor immune effect without obvious autoimmune side effects, promoting infiltration of T lymphocyte into the tumor site and strengthening phagocytosis of macrophages, even more exciting, significantly reversing pro-tumor M2-like tumor-associated macrophages (TAMs) to anti-tumor M1-like TAMs. The research may provide a promising strategy to develop high-efficient and low-toxic immunotherapy based on nanotechnology.


Assuntos
Neoplasias da Mama , Inibidores de Checkpoint Imunológico , Neoplasias da Mama/terapia , Feminino , Humanos , Imunoterapia , Fagocitose , Terapia Fototérmica , Microambiente Tumoral
13.
Small ; 17(47): e2103919, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34623753

RESUMO

Given that traditional anticancer therapies fail to significantly improve the prognoses of triple negative breast cancer (TNBC), new modalities with high efficiency are urgently needed. Herein, by mixing the metal-phenolic network formed by tannic acid (TA), bleomycin (BLM), and Fe3+ with glutathione peroxidase 4 (GPX4) inhibitor (ML210) loaded hollow mesoporous Prussian blue (HMPB) nanocubes, the HMPB/ML210@TA-BLM-Fe3+ (HMTBF) nanocomplex is prepared to favor the ferroptosis/apoptosis synergism in TNBC. During the intracellular degradation, Fe3+ /Fe2+ conversion mediated by TA can initiate the Fenton reaction to drastically upregulate the reactive oxygen species level in cells, subsequently induce the accumulation of lipid peroxidation, and thereby cause ferroptotic cell death; meanwhile, the released ML210 efficiently represses the activity of GPX4 to activate ferroptosis pathway. Besides, the chelation of Fe2+ with BLM leads to in situ BLM toxification at tumor site, then triggers an effective apoptosis to synergize with ferroptosis for tumor therapy. As a result, the superior in vivo antitumor efficacy of HMTBF is corroborated in a 4T1 tumor-bearing mice model regarding tumor growth suppression, indicating that the nanoformulations can serve as efficient ferroptosis and apoptosis inducers for use in combinatorial TNBC therapy.


Assuntos
Ferroptose , Nanopartículas , Neoplasias de Mama Triplo Negativas , Animais , Apoptose , Bleomicina , Linhagem Celular Tumoral , Ferrocianetos , Humanos , Camundongos , Polifenóis , Neoplasias de Mama Triplo Negativas/tratamento farmacológico
14.
J Nanobiotechnology ; 19(1): 261, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34481495

RESUMO

BACKGROUND: Chemodynamic therapy (CDT), employing Fenton or Fenton-like catalysts to convert hydrogen peroxide (H2O2) into toxic hydroxyl radicals (·OH) to kill cancer cells, holds great promise in tumor therapy due to its high selectivity. However, the therapeutic effect is significantly limited by insufficient intracellular H2O2 level in tumor cells. Fortunately, ß-Lapachone (Lapa) that can exert H2O2-supplementing functionality under the catalysis of nicotinamide adenine dinucleotide (phosphate) NAD(P)H: quinone oxidoreductase-1 (NQO1) enzyme offers a new idea to solve this problem. However, extensive DNA damage caused by high levels of reactive oxygen species can trigger the "hyperactivation" of poly(ADP-ribose) polymerase (PARP), which results in the severe interruption of H2O2 supply and further the reduced efficacy of CDT. Herein, we report a self-amplified nanocatalytic system (ZIF67/Ola/Lapa) to co-deliver the PARP inhibitor Olaparib (Ola) and NQO1-bioactivatable drug Lapa for sustainable H2O2 production and augmented CDT ("1 + 1 + 1 > 3"). RESULTS: The effective inhibition of PARP by Ola can synergize Lapa to enhance H2O2 formation due to the continuous NQO1 redox cycling. In turn, the high levels of H2O2 further react with Co2+ to produce the highly toxic ·OH by Fenton-like reaction, dramatically improving CDT. Both in vitro and in vivo studies demonstrate the excellent antitumor activity of ZIF67/Ola/Lapa in NQO1 overexpressed MDA-MB-231 tumor cells. Importantly, the nanocomposite presents minimal systemic toxicity in normal tissues due to the low NQO1 expression. CONCLUSIONS: This design of nanocatalytic system offers a new paradigm for combing PARP inhibitor, NQO1-bioactivatable drug and Fenton-reagents to obtain sustained H2O2 generation for tumor-specific self-amplified CDT.


Assuntos
Antineoplásicos/farmacologia , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Apoptose , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/metabolismo , Camundongos , NAD(P)H Desidrogenase (Quinona) , Nanopartículas , Naftoquinonas , Poli(ADP-Ribose) Polimerase-1 , Espécies Reativas de Oxigênio/metabolismo
15.
Proc Natl Acad Sci U S A ; 115(27): 7033-7038, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29915035

RESUMO

The glucose transporter GLUT1, a plasma membrane protein that mediates glucose homeostasis in mammalian cells, is responsible for constitutive uptake of glucose into many tissues and organs. Many studies have focused on its vital physiological functions and close relationship with diseases. However, the molecular mechanisms of its activation and transport are not clear, and its detailed distribution pattern on cell membranes also remains unknown. To address these, we first investigated the distribution and assembly of GLUT1 at a nanometer resolution by super-resolution imaging. On HeLa cell membranes, the transporter formed clusters with an average diameter of ∼250 nm, the majority of which were regulated by lipid rafts, as well as being restricted in size by both the cytoskeleton and glycosylation. More importantly, we found that the activation of GLUT1 by azide or MßCD did not increase its membrane expression but induced the decrease of the large clusters. The results suggested that sporadic distribution of GLUT1 may facilitate the transport of glucose, implying a potential association between the distribution and activation. Collectively, our work characterized the clustering distribution of GLUT1 and linked its spatial structural organization to the functions, which would provide insights into the activation mechanism of the transporter.


Assuntos
Transportador de Glucose Tipo 1/metabolismo , Microdomínios da Membrana/metabolismo , Citoesqueleto , Transportador de Glucose Tipo 1/química , Glicosilação , Células HeLa , Humanos , Microdomínios da Membrana/química , Microscopia
16.
Ecotoxicol Environ Saf ; 217: 112233, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33862430

RESUMO

A microwave (MA) irradiation-persulfate-formate system was constructed to detoxify Cr contamination and solidify the geopolymerization of the alkali-activated composite material. Three series of experiments were correspondingly conducted to evaluate the treatment for the chromate-contaminated soil. The changes in the molar ratios of formate to persulfate and the mass rates of fortifier to soil led to a significantly greater reduction of CrVI in the detoxification experiments. The increase of blast furnace slag from 50% to 80% in the composite cementitious materials (CCM) intensified the immobilization efficiencies of chromate and the compressive strengths of geopolymer blocks. MA irradiation potentially enhanced the binding of Ca cations to the aluminosilicate compounds. The degree of reaction in the phenomenological kinetics model mathematically verified the geopolymerization process. Ettringite was formed within the structure of the geopolymer in the coupling system. Sulfate radicals released from persulfate not only contributed to the detoxification process but also strengthened the immobilization process.


Assuntos
Cromatos/análise , Recuperação e Remediação Ambiental/métodos , Micro-Ondas , Poluentes do Solo/análise , Álcalis , Silicatos de Alumínio , Poluição Ambiental , Formiatos , Solo/química , Sulfatos
17.
Ecotoxicol Environ Saf ; 213: 112003, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588188

RESUMO

A green rust-coated expanded perlite (GR-coated Exp-p) microelectrode was synthesized and incorporated into a column-mode three-dimensional electrokinetic (3D-EK) platform to effectively pursue a continuous Cr(VI) removal from the aqueous solution. Brucite-like layers of GR were decorated onto the Exp-p material. The molar ratio of Fe(II) to Fe(III) played a most vital role among the three synthesis factors in influencing the performance of the particle electrode. For the equilibrium adsorption experiments, the target maximum adsorption capacity of 122 mg/g was predicted by a target optimizer and desirability function at the conditions following the pH of 4.7, the initial concentration of 172.4 mg/L, the dosage of 0.28 g/L, and the temperature of 28.96 °C, respectively. SO42-, Cl-, and NO3- fiercely competed with Cr(VI) anions in the acidic conditions for the locally positive sites. A low concentration and a slow flow were favored in the column-mode 3D-EK platform. The pseudo-first-order and Langmuir models were suitable for describing the kinetics and isotherms of the adsorption process, respectively. Cr(VI) anions were electrostatically attracted to the silanol groups and GR surface of the adsorbent, subsequently reduced in both heterogeneity and homogeneity, and finally immobilized by coordinating with silanediol groups and silanetriol groups.


Assuntos
Cromo/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Óxido de Alumínio , Ânions , Eletrodos , Compostos Férricos , Concentração de Íons de Hidrogênio , Cinética , Dióxido de Silício , Temperatura , Água , Poluentes Químicos da Água/análise
18.
J Environ Manage ; 280: 111697, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33246753

RESUMO

Biohazard performance of Sr radionuclide can be significantly magnified by its release from the contaminated sedimentation. In this study, hydroxyapatite nanoparticle-functionalized activated carbon electrode (AC-HAP) was synthesized and stacked to the cathode compartment of the electrokinetic (EK) system to develop a unipolar three-dimensional (3D) electrochemical process for Sr2+ removal from spiked soils. Sr2+ adsorption by AC-HAP can be fitted by the pseudo-first-order and pseudo-second-order kinetic models and the Langmuir, Freundlich, and Temkin isotherm models. The largest monolayer adsorption capacity of AC-HAP of 69.49 mg g-1 was evaluated in the pH range of 10-12 and at 40 °C. 3D EK further intensified the adsorption process of AC-HAP and the corresponding Sr2+ removal from aqueous environments. Voltage gradients and proposing time had a significant effect on the migration and transmission of Sr2+ in the electrolyzer. The influence of competitive ions on Sr2+ removal in the stock solutions followed Al3+ < Mg2+ < K+ < Na+ < Ca2+ while followed Al3+ < Na+ < K+ < Mg2+ < Ca2+ in 3D EK. The first three cycles for AC-HAP had taken roughly 50% of the reusability percentage. Sr2+ removal from spiked samples in 3D EK was achieved by acid dissolution, electromigration, and selective uptake on particle electrode.


Assuntos
Carvão Vegetal , Nanopartículas , Adsorção , Durapatita , Eletrodos , Solo , Estrôncio
19.
J Environ Sci (China) ; 107: 14-25, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34412777

RESUMO

The layered laurylsulfonate intercalated green rust (lauryl-S GR) was synthesized to evaluate the influence of synthesis parameters and aqueous conditions on the adsorption of CeIV. The maximum adsorption capacity of 305.58 mg/g by lauryl-S GR was predictably obtained. The pseudo-first-order kinetic model was appropriate in fitting the whole uptake process in a weak acid environment. Three isotherm models including Langmuir, Freundlich, and Tempkin were all reliable in depicting the isotherm adsorption process. The maximum monolayer adsorption capacity of lauryl-S GR towards CeIV was 315.46 mg/g. Ce species including CeO and Ce2O3 besides CeO2 were matched in the XPS distribution, directly indicating the reduction reaction brought by FeII in the GR occurred to hydrated CeIV ions during the adsorption. Nano-sized Ce particles attached to the lauryl-S GRs after the adsorption experiments were observed in the morphological characterization. Flocculated materials were formed on the surface of the lauryl-S GR at a pH of 7, which further reduced the active sites and disrupted the continuous uptake of CeIV to the lauryl-S GR. This study expands the application of GRs and supplies an ideal iron-based material for the construction of the affiliated recovery pathway to the traditional separation of Ce.


Assuntos
Cério , Purificação da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética
20.
Semin Cell Dev Biol ; 73: 31-44, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28723581

RESUMO

The cell membrane, involved in almost all communications of cells and surrounding matrix, is one of the most complicated components of cells. Lack of suitable methods for the detection of cell membranes in vivo has sparked debates on the biochemical composition and structure of cell membranes over half a century. The development of single molecule techniques, such as AFM, SMFS, and TREC, provides a versatile platform for imaging and manipulating cell membranes in biological relevant environments. Here, we discuss the latest developments in AFM and the progress made in cell membrane research. In particular, we highlight novel structure models and dynamic processes, including the mechanical properties of the cell membranes.


Assuntos
Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Microscopia de Força Atômica , Modelos Estruturais , Animais , Membrana Celular/química , Humanos , Nanotecnologia
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