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1.
Appl Bionics Biomech ; 2022: 8629583, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401788

RESUMO

Objective: We aimed to explore the risk factors for coal workers' pneumoconiosis and to further explore the significance of mitochondrial fission and fusion factors in CWP and verify the feasibility of mitochondrial fission and fusion factors as diagnostic and therapeutic targets. Methods: The data of 168 cases were collected, and they were divided into a healthy control group (40 cases), dust exposure control group (61 cases), and CWP group (67 cases) and entered into SPSS 24.0. The statistical data were analyzed by the chi-square test or Fisher's exact probability method. The variables with statistically significant differences of the univariate analysis results were included in the generalized linear model. Test level was α = 0.05. Blood samples were collected to detect the ROS content, MDA content, and SOD activity. The mRNA expression levels of OPA1, Drp1, MFN2, Fis1, Col I, Col III, and α-SMA were determined by q-PCR. The protein expression levels of OPA1, Drp1, MFN2, Fis1, Col I, Col III, and α-SMA were detected by western blot. Results: Generalized linear regression analysis showed that lower school education, no respiratory protective measures, the working age beyond 15 years, and the type of work like coal mine drillers were the risk factors for CWP. With the aggravation of CWP, the degree of fibrosis and inflammation increased oxidative damage, increased mitochondrion division, and decreased fusion, which were more sensitive in the second and third stages of CWP. Conclusion: The results in this found that mitochondria are injured by fission and fusion in the CWP patients. Detection of the mitochondria fission and fusion factors provides the application value to evaluate the injury degree and progress of CWP and the clues for finding the real and effective screening and diagnosis biomarkers.

2.
Micromachines (Basel) ; 12(2)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499221

RESUMO

In this paper, the effects of annealing temperature and other process parameters on spin-coated indium oxide thin film transistors (In2O3-TFTs) were studied. The research shows that plasma pretreatment of glass substrate can improve the hydrophilicity of glass substrate and stability of the spin-coating process. With Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) analysis, it is found that In2O3 thin films prepared by the spin coating method are amorphous, and have little organic residue when the annealing temperature ranges from 200 to 300 °C. After optimizing process conditions with the spin-coated rotating speed of 4000 rpm and the annealing temperature of 275 °C, the performance of In2O3-TFTs is best (average mobility of 1.288 cm2·V-1·s-1, Ion/Ioff of 5.93 × 106, and SS of 0.84 V·dec-1). Finally, the stability of In2O3-TFTs prepared at different annealing temperatures was analyzed by energy band theory, and we identified that the elimination of residual hydroxyl groups was the key influencing factor. Our results provide a useful reference for high-performance metal oxide semiconductor TFTs prepared by the solution method.

3.
Environ Toxicol ; 35(2): 176-187, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31633292

RESUMO

Mesoporous silica is a drug carrier with strong targeting, large loading capacity, and easy modification of its surface while its toxicity draws increasing attention recently. In this study, we evaluated the impact of SBA-15 nanomaterials on hippocampal neurons. We found that SBA-15 induces oxidative damage to hippocampal neurons HT22, which further activates autophagy. Treatment with the mammalian target of rapamycin (mTOR) inhibitor AZD8055, the phosphorylation level of mTOR and P70S6K reduced and increased levels of p-AMPK meaning that the adenosine-activated protein kinase (AMPK)/mTOR/P70S6K pathway is involved in SBA-15 induced autophagy of HT22. These results suggested that mesoporous silica material SBA-15 might affect central nervous cells via oxidative stress activation of the AMPK/mTOR/P70S6K pathway, which provides a theoretical basis for safe administration of such materials in patients.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Dióxido de Silício/toxicidade , Serina-Treonina Quinases TOR/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Linhagem Celular , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Camundongos , Nanoestruturas/química , Neurônios/metabolismo , Neurônios/patologia , Fosforilação , Transdução de Sinais , Dióxido de Silício/química
4.
Nanoscale Res Lett ; 14(1): 80, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30838466

RESUMO

In this work, a low leakage current ZrO2 was fabricated for sputter indium gallium zinc oxide (IGZO) thin-film transistor using direct inkjet-printing technology. Spin-coated and direct inkjet-printed ZrO2 were prepared to investigate the film formation process and electrical performance for different process. Homogeneous ZrO2 films were observed through the high-resolution TEM images. The chemical structure of ZrO2 films were investigated by XPS measurements. The inkjet-printed ZrO2 layer upon IGZO showed a superior performance on mobility and off state current, but a large Vth shift under positive bias stress. As a result, the TFT device based on inkjet-printed ZrO2 exhibited a saturation mobility of 12.4 cm2/Vs, an Ion/Ioff ratio of 106, a turn on voltage of 0 V and a 1.4-V Vth shift after 1-h PBS strain. Higher density films with less oxygen vacancy were responsible for low off state current for the printed ZrO2 device. The mechanism of deteriorated performance on PBS test can be ascribed to the In-rich region formed at the back channel which easily absorbs H2O and oxygen. The absorbed H2O and oxygen capture electrons under positive bias stress, serving as acceptors in TFT device. This work demonstrates the film formation process of direct inkjet-printed and spin-coated oxide films and reveals the potential of direct inkjet-printed oxide dielectric in high-performance oxide TFT device.

5.
ACS Appl Mater Interfaces ; 11(5): 5193-5199, 2019 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-30624890

RESUMO

We have successfully developed an ink system containing inexpensive raw materials through a simple process and have printed ZrO x dielectric film at a relatively low annealing temperature of 250 °C. The ZrO x dielectric film afforded a leakage current density of 5.4 × 10-6 A/cm2 at 1 MV/cm and a dielectric constant of 10 and shows a promising future for flexible electronics. The ink system shows a temperature-induced gelation behavior, and a gel network is formed when the temperature rises. A high concentration of oxide precursors is obtained near the network area through the absorption function of polymer groups, and thus oxide structure can be formed at a relatively low temperature due to the shorter diffusion path of precursor polymerization. The microstructure of the printed ZrO x film was investigated by high resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS), and the effect of annealing temperature on film structure was studied.

6.
J Colloid Interface Sci ; 527: 87-94, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29783142

RESUMO

In the present study, the responses of microbial products in the biosorption process of Cu(II) onto aerobic granular sludge were evaluated by using batch and spectroscopic approaches. Batch experimental data showed that extracellular polymeric substances (EPSs) contributed to Cu(II) removal from an aqueous solution, especially when treating low metal concentrations, whereas soluble microbial products (SMPs) were released under the metal stress during biosorption process. A three-dimensional excitation-emission matrix (3D-EEM) identified four main fluorescence peaks in the EPS, i.e., tryptophan protein-like, aromatic protein-like, humic-like and fulvic acid-like substances, and their fluorescence intensities decreased gradually in the presence of Cu(II) during the sorption process. Particularly, tryptophan protein-like substances quenched the Cu(II) binding to a much higher extent through a static quenching process with less than one class of binding sites. According to the synchronous fluorescence spectra, the whole fluorescence intensity of released SMP samples expressed an increased trend with different degrees along with contact time. Two-dimensional correlation spectroscopy (2D-COS) suggested that the fulvic-like fluorescence fraction might be more susceptible to metal exposure than other fractions. The result of molecular weight distribution demonstrated that the SMPs released from the biosorption process differed significantly according to contact time. The result obtained could provide new insights into the responses of microbial products from aerobic granular sludge with heavy metal treatment.


Assuntos
Bactérias/metabolismo , Cobre/química , Polímeros/química , Esgotos/química , Poluentes Químicos da Água/química , Adsorção , Biopolímeros/química , Cátions Bivalentes , Cinética , Tamanho da Partícula , Esgotos/microbiologia , Propriedades de Superfície , Termodinâmica , Eliminação de Resíduos Líquidos/métodos , Purificação da Água
7.
Langmuir ; 34(22): 6413-6419, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29750535

RESUMO

Many methods have been reported to prevent the nonuniformity of inkjet printing structures. Most of them depend on the balance of the capillary flow in the printing pattern during the evaporation of the solvent. However, as the relation of evaporation and capillary flow can obviously vary among different ink systems, it is difficult for a method to fit most of the situations. Therefore, it would be a promising way to eliminate any capillary flow before solvent evaporation so that morphology of the printing structure will not be affected by the evaporation behavior of the ink system. In this paper, a novel method of direct inkjet printing of a uniform metal oxide structure is reported. We introduce a polymer polyacrylamide and a surfactant FSO into a sol-gel ink system, and the new ink system can gel from the printing pattern edge to center as temperature increases because of the cross-linking of the polymer chains. By that means, transport of solute molecules and solvent molecules is limited. Meanwhile, the surfactant can ensure that the solute in the central liquid phase deposits uniformly by enhancing the Marangoni flow during the gelation process. The ZrO2 film with uniform morphology was fabricated by drying and annealing the gelating film and afforded a leakage current density of 7.48 × 10-7 A cm-2 at 1 MV and a breakdown field of 1.9 MV cm-1 at an annealing temperature of 250 °C.

8.
Bioprocess Biosyst Eng ; 41(6): 841-850, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29523965

RESUMO

In present study, the characteristics of soluble microbial products (SMP) were evaluated in aerobic granular sludge system during denitrification process under different chemical oxygen demand/nitrogen (C/N) ratios. Batch experiment showed that the effluent nitrate (NO3--N) concentration were 15.24 ± 1.83 and 1.72 ± 1.53 mg/L at C/N ratio of 1 and 6, respectively. For the release of SMP, the protein (PN) and polysaccharide contents increased from 1.23 ± 0.38 and 7.46 ± 1.13 mg/L to 1.80 ± 0.76 and 10.53 ± 1.24 mg/L with increasing C/N ratios, respectively. Excitation-emission matrix identified four peaks in SMP, including aromatic PN-like, tryptophan PN-like, fulvic acid-like and humic acid-like substances. Fluorescence regional integration suggested that biodegradable PN-like substances occupied the percentage between 53.0 and 61.7% in SMP. Synchronous fluorescence spectra coupled with two-dimensional correlation spectroscopy indicated that the release of SMP fractions in the early stage (0-150 min) changed in the following sequences: PN-like fraction > fulvic acid-like fraction.


Assuntos
Desnitrificação , Nitratos/análise , Polissacarídeos/análise , Proteínas/análise , Esgotos/análise , Esgotos/microbiologia , Águas Residuárias/microbiologia , Aerobiose , Nitratos/metabolismo , Polissacarídeos/biossíntese , Proteínas/metabolismo , Purificação da Água
9.
Bioresour Technol ; 249: 241-246, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29049982

RESUMO

In present study, the characterization of soluble microbial products (SMP) was evaluated in a partial nitrification sequencing batch biofilm reactor (SBBR). During the stable operation of SBBR, the NH4+-N removal efficiency and nitrite accumulation ratio were 96.70±0.41% and 93.77±1.04%, respectively. According to excitation-emission matrix (EEM), the intensities of protein-like substances were reduced under anoxic and aerobic phases, whereas humic-like substances had little change during the whole cycle. Parallel factor analysis (PARAFAC) further indentified two components and their fluorescence intensity scores were both reduced. Synchronous fluorescence spectra revealed that the fluorescence intensity of protein-like fraction decreased with reaction time. Two-dimensional correlation spectroscopy (2D-COS) further demonstrated that protein-like fraction might decrease earlier than the other fractions. The information obtained in present study is of fundamental significance for understanding the key components in SMP and their changes in partial nitrification system by using a spectral approach.


Assuntos
Nitrificação , Águas Residuárias , Amônia , Biofilmes , Reatores Biológicos , Nitrogênio
10.
Nanomaterials (Basel) ; 7(12)2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-29186081

RESUMO

In this paper, an alumina-zirconia (Al2O3-ZrO2) nanolaminate dielectric was fabricated by spin-coating and the performance was investigated. It was found that the properties of the dielectric can be adjusted by changing the content of Al2O3/ZrO2 in nanolaminates: when the content of Al2O3 was higher than 50%, the properties of nanolaminates, such as the optical energy gap, dielectric strength (Vds), capacitance density, and relative permittivity were relatively stable, while the change of these properties became larger when the content of Al2O3 was less than 50%. With the content of ZrO2 varying from 50% to 100%, the variation of these properties was up to 0.482 eV, 2.12 MV/cm, 135.35 nF/cm², and 11.64, respectively. Furthermore, it was demonstrated that the dielectric strength of nanolaminates were influenced significantly by the number (n) of bilayers. Every increment of one Al2O3-ZrO2 bilayer will enhance the dielectric strength by around 0.39 MV/cm (Vds ≈ 0.86 + 0.39n). This could be contributed to the amorphous alumina which interrupted the grain boundaries of zirconia.

11.
Nanoscale Res Lett ; 12(1): 546, 2017 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-28948539

RESUMO

Inkjet-printed silver gate electrode with low electrical resistivity was fabricated by UV curing method. By adjusting the UV curing time and the distance between the samples and UV lamp, the effects of UV curing conditions on the electrical resistivity of the silver films were studied, and the lowest electrical resistivity of 6.69 × 10-8 Ω·m was obtained. Besides, the UV-cured silver films have good adhesion to the glass substrates, with adhesion strength of 4B (ASTM international standard). Our work offered an easy and low temperature approach to fabricate inkjet-printed silver electrodes with low electrical resistivity.

12.
Materials (Basel) ; 10(8)2017 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-28825652

RESUMO

Solution-processed high-k dielectric TFTs attract much attention since they cost relatively little and have a simple fabrication process. However, it is still a challenge to reduce the leakage of the current density of solution-processed dielectric TFTs. Here, a simple solution method is presented towards enhanced performance of ZrO2 films by intentionally increasing the concentration of precursor. The ZrO2 films not only exhibit a low leakage current density of 10-6 A/cm² at 10 V and a breakdown field of 2.5 MV/cm, but also demonstrate a saturation mobility of 12.6 cm²·V-1·s-1 and a Ion/Ioff ratio of 106 in DC pulse sputtering IGZO-TFTs based on these films. Moreover, the underlying mechanism of influence of precursor concentration on film formation is presented. Higher concentration precursor results in a thicker film within same coating times with reduced ZrO2/IGZO interface defects and roughness. It shows the importance of thickness, roughness, and annealing temperature in solution-processed dielectric oxide TFT and provides an approach to precisely control solution-processed oxide films thickness.

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