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1.
Molecules ; 27(3)2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35164323

RESUMEN

Ceramic membranes have the advantages of high mechanical strength and thermal stability and are promising candidates for membrane distillation. Ceramic membranes are generally designed to have a multilayer structure with different pore sizes to create a high liquid entry pressure and obtain a high permeability. However, these structural characteristics pose significant difficulties in predicting permeate flux in a ceramic membrane contactor for vacuum membrane distillation (VMD). Here, a modeling approach was developed to simulate the VMD process and verified by comparing the simulated results with the experimental data. Furthermore, correlations are proposed to simplify the calculations of permeate flux for VMD using asymmetric ceramic membranes by assuming those multilayers to be an effectively quasi-symmetric layer and by introducing a correction factor. The simulation results indicated that this simplified correlation was effective and enabled a quick estimation of the effect of membrane parameters on permeate flux.

2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 40(6): 418-20, 2016 Nov.
Artículo en Zh | MEDLINE | ID: mdl-29792602

RESUMEN

Hospital information technology has introduced a new mode of colaborative work based on heterogeneous systems and it wil become the new norm. The article ilustrates some successful typical cases of information exchange in the heterogeneous systems for colaborative work in Chinese PLA general hospital and puts forward some principles in the hospital's design of heterogeneous information systems.


Asunto(s)
Sistemas de Información en Hospital , Sistemas de Información
3.
Membranes (Basel) ; 14(2)2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38392661

RESUMEN

Thin, supported inorganic mesoporous membranes are used for the removal of salts, small molecules (PFAS, dyes, and polyanions) and particulate species (oil droplets) from aqueous sources with high flux and selectivity. Nanofiltration membranes can reject simple salts with 80-100% selectivity through a space charge mechanism. Rejection by size selectivity can be near 100% since the membranes can have a very narrow size distribution. Mesoporous membranes have received particular interest due to their (potential) stability under operational conditions and during defouling operations. More recently, membranes with extreme stability became interesting with the advent of in situ fouling mitigation by means of ultrasound emitted from within the membrane structure. For this reason, we explored the stability of available and new membranes with accelerated lifetime tests in aqueous solutions at various temperatures and pH values. Of the available ceria, titania, and magnetite membranes, none were actually stable under all test conditions. In earlier work, it was established that mesoporous alumina membranes have very poor stability. A new nanofiltration membrane was made of cubic zirconia membranes that exhibited near-perfect stability. A new ultrafiltration membrane was made of amorphous silica that was fully stable in ultrapure water at 80 °C. This work provides details of membrane synthesis, stability characterization and data and their interpretation.

4.
Neuro Oncol ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38416702

RESUMEN

BACKGROUND: Meningioma is the most common primary intracranial tumor with high frequency of postoperative recurrence, yet the biology of meningioma malignancy process is still obscure. METHODS: To identify potential therapeutic targets and tumor suppressors, we performed single-cell transcriptome analysis through meningioma malignancy, which included 18 samples spanning normal meninges, benign and high grade in situ tumors, and lung metastases, for extensive transcriptome characterization. Tumor suppressor candidate gene and molecular mechanism were functionally validated at animal model and cellular level. RESULTS: Comprehensive analysis and validation in mice and clinical cohorts indicated Clusterin (CLU) had suppressive function for meningioma tumorigenesis and malignancy by inducing mitochondria damage and triggering type I interferon pathway dependent on its secreted isoform, and the inhibition effect was enhanced by TNFα as TNFα also induced type I interferon pathway. The expression of CLU was upregulated by histone deacetylase inhibition. Meanwhile, both intra- and extra-cellular CLU overexpression enhanced macrophage polarization towards M1 phenotype and TNFα production, thus promoted tumor killing and phagocytosis. CONCLUSIONS: CLU might be a key brake of meningioma malignance by synchronous modulating tumor cells and their microenvironment. Our work provides comprehensive insights into meningioma malignancy and a potential therapeutic strategy.

5.
Front Biosci (Landmark Ed) ; 29(5): 198, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38812324

RESUMEN

BACKGROUND: DELLA protein is a crucial factor which played pivotal roles in regulating numerous intriguing biological processes in plant development and abiotic stress responses. However, little is known about the function and information of DELLA protein in Chinese cabbage. METHODS: Using 5 DELLA gene sequences in Arabidopsis Thaliana as probes, 5 DELLA genes in Chinese cabbage were identified by Blast search in Chinese cabbage database (Brassica database (BRAD)). The National Center for Biotechnology Information (NCBI), ExPaSy, SWISS-MODEL, DNAMAN, MEGA 11, PlantCARE were used to identify and analyze the DELLA gene family of Chinese cabbage. Gene expression was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). The function of BraA10gRGL3 was verified by overexpression and phenotypic analysis of BraA10gRGL3 and yeast hybrid. RESULTS: In this study, 5 BraDELLAs homologous to Arabidopsis thaliana were identified and cloned based on the Brassica database, namely, BraA02gRGL1, BraA05gRGL2, BraA10gRGL3, BraA06gRGA and BraA09gRGA. All BraDELLAs contain the DELLA, TVHYNP, and GRAS conserved domains. Cis-element analysis revealed that the promoter regions of these 5 DELLA genes all contain light-responsive elements, TCT motif, I-box, G-box, and box 4, which are associated with GA signaling. Transcriptome analysis results proved that the expression of BraA02gRGL1, BraA05gRGL2, and BraA10gRGL3 in Y2 at different growth stages were lower than them in Y7, which is consistent with the phenotype that Y7 exhibited stronger stress tolerance than Y2. It is worth emphasizing that even through the overexpression of BraA10gRGL3-Y7 in Arabidopsis resulted in smaller leaf size and lower fresh weight compared to the wild type (WT) Arabidopsis: Columbia, a stronger response to abiotic stresses was observed in BraA10gRGL3-Y7. It indicated that BraA10gRGL3-Y7 can improve the stress resistance of plants by inhibiting their growth. Moreover, the yeast two-hybrid experiment confirmed that BraA10gRGL3-Y7 can interacted with BraA05gGID1a-Y7, BraA04gGID1b1, BraA09gGID1b3-Y2, and BraA06gGID1c, whereas BraA10gRGL3-Y2 cannot interact with any BraGID1. CONCLUSIONS: Collectively, BraDELLAs play important role in plant development and response to abiotic stress. The differences in amino acid sequences between BraA10gRGL3-Y2 and BraA10gRGL3-Y7 may result in variations in their protein binding sites, thus affecting their interaction with the BraGID1 family proteins. This systematic analysis lays the foundation for further study of the functional characteristics of DELLA genes of Chinese cabbage.


Asunto(s)
Arabidopsis , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Brassica rapa/genética , Brassica rapa/crecimiento & desarrollo , Brassica rapa/metabolismo , Estrés Fisiológico/genética , Filogenia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Perfilación de la Expresión Génica , Plantas Modificadas Genéticamente/genética , Genes de Plantas , Genoma de Planta
6.
Mol Vis ; 19: 944-54, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23687431

RESUMEN

PURPOSE: Single nucleotide polymorphisms (SNPs) of age-related maculopathy susceptibility protein 2/HtrA serine peptidase 1 (ARMS2/HTRA1) and complement factor H (CFH) have been reported to be associated with age-related macular degeneration (AMD). The purpose of this study was to investigate the association of ARMS2/HTRA1 and CFH SNPs with early age-related maculopathy (ARM) in a Han Chinese cohort. METHODS: The cohort consisted of 315 unrelated subjects, including 158 patients with early ARM and 157 recruited controls. Early ARM was diagnosed and graded according to the Age-Related Eye Disease Study criteria. Four SNPs in ARMS2/HTRA1 and six SNPs in CFH previously reported to be associated with AMD were genotyped using TaqMan genotyping assays. Logistic regression implemented with the R statistical language was used for association analysis. RESULTS: None of the ARMS2/HTRA1 and CFH SNPs showed any significant association with early ARM (all p>0.453), with the odds ratios ranging from 0.88 to 1.17. None of the SNPs were associated with unilateral or bilateral early ARM or any grade of early ARM (all p>0.249). CONCLUSIONS: The association of ARMS2/HTRA1 and CFH SNPs in early ARM was not detected in our cohort. The findings in the current study indicated that the effects of ARMS2/HTRA1 and CFH in early ARM could be much lower compared to those in AMD.


Asunto(s)
Pueblo Asiatico/genética , Estudios de Asociación Genética , Degeneración Macular/genética , Polimorfismo de Nucleótido Simple/genética , Proteínas/genética , Serina Endopeptidasas/genética , Edad de Inicio , Anciano , Anciano de 80 o más Años , China/epidemiología , Estudios de Cohortes , Factor H de Complemento/genética , Demografía , Femenino , Predisposición Genética a la Enfermedad , Serina Peptidasa A1 que Requiere Temperaturas Altas , Humanos , Desequilibrio de Ligamiento/genética , Degeneración Macular/epidemiología , Masculino , Persona de Mediana Edad
7.
Zhongguo Yi Liao Qi Xie Za Zhi ; 37(5): 327-9, 339, 2013 Sep.
Artículo en Zh | MEDLINE | ID: mdl-24409786

RESUMEN

The format of medical image file conformance to DICOM standard have important influence on users of the PACS. This paper summarized the results of the writer's study on the image file conformance to DICOM standard about medical imaging device for many years. The questions of medical image file no conformance to DICOM standard are pointed in detail and the questions resulted from the troubled image files are analyzed. Finally, the methods of avoiding image file no conformance to DICOM standard are presented.


Asunto(s)
Diagnóstico por Imagen/instrumentación , Diagnóstico por Imagen/normas
8.
Front Biosci (Landmark Ed) ; 28(12): 345, 2023 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-38179748

RESUMEN

BACKGROUND: Chinese cabbage (Brassica rapa L. ssp. pekinensis) is one of the most popular vegetables in China because of its taste and health benefits. The area of production has obvious effects on the quality of Chinese cabbage. However, metabolite profiling and variations in different production areas are still unclear. METHODS: Here, widely targeted metabolite analyses based on the ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) approach were performed to study the metabolite profiling of Chinese cabbage planted in the Jiaozhou and Jinan areas. RESULTS: A total of 531 metabolites were detected, of which 529 were present in the Chinese cabbage from both areas, 108 were found to be chemicals related to Chinese traditional medicine, and 79 were found to correspond to at least one disease. Chinese cabbage is rich in nutritious substances such as lipids, phenolic acids, amino acids and derivatives, nucleotides and derivatives, organic acids, flavonoids, glucosinolates, saccharides, alcohols, and vitamins. Comparative analysis showed that the metabolic profiles differed between areas, and 89 differentially altered metabolites (DAMs) were characterized. Of these, 78 DAMs showed higher levels in Jinan Chinese cabbage, whereas 11 had higher levels in Jiaozhou Chinese cabbage. Two metabolites, S-(Methyl)glutathione and nicotinic acid adenine dinucleotide, were unique in Jiaozhou Chinese cabbage. Based on Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the DAMs were enriched into 23 pathways, of which tryptophan metabolism and thiamine metabolism were the significant enrichment pathways. CONCLUSIONS: This study provides new insights into the metabolite profiles and production areas affecting the metabolite variations of Chinese cabbage, which will be useful for functional Chinese cabbage cultivation.


Asunto(s)
Brassica rapa , Brassica , Brassica rapa/genética , Brassica rapa/metabolismo , Cromatografía Liquida , Perfilación de la Expresión Génica , Espectrometría de Masas en Tándem , Brassica/química , Brassica/genética , Regulación de la Expresión Génica de las Plantas
9.
Adv Sci (Weinh) ; 9(3): e2103952, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34825781

RESUMEN

Aqueous zinc-ion batteries (ZIBs) are one of the most ideal candidates for grid-scale energy storage applications due to their excellent price and safety advantages. However, formation of Zn dendrites and continuous side reactions during cycling result in serious instability problems for ZIBs. In this work, the authors develop a facile and versatile plasma-induced nitrogen-doped Zn (N-Zn) foil for dendrite-free Zn metal anode. Benefitting from the uniform nucleation sites and enhanced surface kinetics, the N-Zn anode exhibits exceptionally low overpotential (around 23 mV) at 1 mA cm-2 and can be cycled for over 3000 h under 1 mA cm-2 because of the enhanced interface behavior. The potential application of N-Zn anode is also confirmed by introducing a full Zn/MnO2 battery with outstanding capacity stability for 2000 cycles at 1 A g-1 . Overall, this work offers new fundamental insights into homogenizing Zn electrodeposition processes by pre-introduced active nucleation sites and provides a novel direction of interface design engineering for ultra-stable Zn metal anode.

10.
Chem Commun (Camb) ; 58(7): 993-996, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34935792

RESUMEN

A facile oxygen plasma treatment strategy is proposed to promote zinc dendrite inhibition by modifying the surface oxygen functional groups. The plasma-treated zinc electrodes achieved an extended working lifespan of 3800 h with an average Coulombic efficiency of over 99% for 1000 cycles when applied in full batteries. This work provides great prospects for the fabrication of long-life zinc batteries for grid systems.

11.
Proc Natl Acad Sci U S A ; 105(17): 6227-31, 2008 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-18434547

RESUMEN

Crossed molecular beam experiments and accurate quantum dynamics calculations have been carried out to address the long standing and intriguing issue of the forward scattering observed in the F + H(2) --> HF(v' = 3) + H reaction. Our study reveals that forward scattering in the reaction channel is not caused by Feshbach or dynamical resonances as in the F + H(2) --> HF(v' = 2) + H reaction. It is caused predominantly by the slow-down mechanism over the centrifugal barrier in the exit channel, with some small contribution from the shape resonance mechanism in a very small collision energy regime slightly above the HF(v' = 3) threshold. Our analysis also shows that forward scattering caused by dynamical resonances can very likely be accompanied by forward scattering in a different product vibrational state caused by a slow-down mechanism.

12.
Proc Natl Acad Sci U S A ; 105(35): 12662-6, 2008 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-18687888

RESUMEN

Reaction resonances are transiently trapped quantum states along the reaction coordinate in the transition state region of a chemical reaction that could have profound effects on the dynamics of the reaction. Obtaining an accurate reaction potential that holds these reaction resonance states and eventually modeling quantitatively the reaction resonance dynamics is still a great challenge. Up to now, the only viable way to obtain a resonance potential is through high-level ab initio calculations. Through highly accurate crossed-beam reactive scattering studies on isotope-substituted reactions, the accuracy of the resonance potential could be rigorously tested. Here we report a combined experimental and theoretical study on the resonance-mediated F + HD --> HF + D reaction at the full quantum state resolved level, to probe the resonance potential in this benchmark system. The experimental result shows that isotope substitution has a dramatic effect on the resonance picture of this important system. Theoretical analyses suggest that the full-dimensional FH(2) ground potential surface, which was believed to be accurate in describing the resonance picture of the F + H(2) reaction, is found to be insufficiently accurate in predicting quantitatively the resonance picture for the F + HD --> HF + D reaction. We constructed a global potential energy surface by using the CCSD(T) method that could predict the correct resonance peak positions as well as the dynamics for both F + H(2) --> HF + H and F + HD --> HF + D, providing an accurate resonance potential for this benchmark system with spectroscopic accuracy.

13.
ACS Appl Mater Interfaces ; 13(32): 38761-38772, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-34370441

RESUMEN

Wearable electromagnetic interference (EMI) shielding fabrics are highly desirable with the rapid development of electronic devices and wireless communications where electromagnetic pollution is a great concern for human health and the reliability of precision equipment. The balance between EMI shielding efficiency (SE) and the flexibility of fabric is still challenging because of the generally opposite requirements for coating thickness. In this work, MXene/insulative polymer coating with an alternating structure is fabricated via a stepwise assembly technique to judiciously combine excellent shielding elements, a reasonable structure, and high nanofiller content together in the coating. Owing to this novel strategy, the coating with nanoscale thickness (∼500 nm) has realized the commercial requirement for EMI SE and well retained the flexibility and air permeability of the fabric. Compared with the corresponding pure MXene coating, such multilayered coating demonstrates 138.95% enhancement of EMI SE due to the improved dielectrical properties and intensive multiple reflections of electromagnetic waves. Additionally, this hybrid coating also acts as an excellent fire-resistant barrier for the inner flammable fabric to protect human beings and electronic devices in case of accidental fire. This work provides new insights into the rational design of shields with nanometer thickness to realize high EMI shielding performance and good fire resistance for new-generation portable and wearable EMI shielding products.

14.
Membranes (Basel) ; 11(9)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34564528

RESUMEN

Support is a necessary foundation for ceramic membranes to achieve high performance. Finding the optimum balance between high performance and low cost is still a significant challenge in the fabrication of ceramic supports. In this study, low-cost fly ash-based ceramic supports with enhanced performance were prepared by the addition of bauxite. The pore structure, mechanical strength, and shrinkage of fly ash/bauxite supports could be tuned by optimizing the bauxite content and sintering temperature. When the sintering temperature and bauxite content were controlled at 1300 °C and 40 wt%, respectively, the obtained membrane supports exhibited a high pure water permeance of approximately 5.36 m3·m-2·h-1·bar-1 and a high bending strength of approximately 69.6 MPa. At the same time, the optimized ceramic supports presented a typical mullite phase and excellent resistance to acid and alkali. This work provides a potential route for the preparation of ceramic membrane supports with characteristics of low cost and high performance.

15.
Membranes (Basel) ; 12(1)2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-35054534

RESUMEN

Ceramic membrane contactors hold great promise for CO2 desorption due to their high mass transfer area as well as the favorable characteristics of ceramic materials to resist harsh operating conditions. In this work, a hydrophobic tubular asymmetric alpha-alumina (α-Al2O3) membrane was prepared by grafting a hexadecyltrimethoxysilane ethanol solution. The hydrophobicity and permeability of the membrane were evaluated in terms of water contact angle and nitrogen (N2) flux. The hydrophobic membrane had a water contact angle of ~132° and N2 flux of 0.967 × 10-5 mol/(m2∙s∙Pa). CO2 desorption from the aqueous monoethanolamine (MEA) solution was conducted through the hydrophobic tubular ceramic membrane contactor. The effects of operating conditions, such as CO2 loading, liquid flow rate, liquid temperature and permeate side pressure, on CO2 desorption flux were investigated. Moreover, the stability of the membrane was evaluated after the immersion of the ceramic membrane in an MEA solution at 373 K for 30 days. It was found that the hydrophobic α-Al2O3 membrane had good stability for CO2 desorption from the MEA solution, resulting in a <10% reduction of N2 flux compared to the membrane without MEA immersion.

16.
J Leukoc Biol ; 110(6): 1171-1180, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34231935

RESUMEN

The outbreak of coronavirus disease 2019 (COVID-19) has now become a pandemic, and the etiologic agent is the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). T cell mediated immune responses play an important role in virus controlling; however, the understanding of the viral protein immunogenicity and the mechanisms of the induced responses are still limited. So, identification of specific epitopes and exploring their immunogenic properties would provide valuable information. In our study, we utilized the Immune Epitope Database and Analysis Resource and NetMHCpan to predict HLA-A2 restricted CD8+ T cell epitopes in structural proteins of SARS-CoV-2, and screened out 23 potential epitopes. Among them, 18 peptides showed strong or moderate binding with HLA-A2 with a T2A2 cell binding model. Next, the mixed peptides induced the increased expression of CD69 and highly expressed levels of IFN-γ and granzyme B in CD8+ T cells, indicating effective activation of specific CD8+ T cells. In addition, the peptide-activated CD8+ T cells showed significantly increased killing to the target cells. Furthermore, tetramer staining revealed that the activated CD8+ T cells mainly recognized seven epitopes. All together, we identified specific CD8+ T cell epitopes in SARS-CoV-2 structural proteins, which could induce the production of specific immune competent CD8+ T cells. Our work contributes to the understanding of specific immune responses and vaccine development for SARS-CoV-2.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , COVID-19/inmunología , Epítopos de Linfocito T/inmunología , Antígeno HLA-A2/inmunología , SARS-CoV-2/inmunología , Proteínas Estructurales Virales/inmunología , Adulto , Femenino , Humanos , Activación de Linfocitos/inmunología , Masculino
17.
Front Immunol ; 11: 1266, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32765487

RESUMEN

Dendritic epidermal T cells (DETCs) are γδ T cells expressing invariant Vγ5Vδ1 T cell receptor (TCR) in murine epidermis. Initially, the development and the maturation of DETC progenitors are mediated by skint-1, TCR, and cytokines in the fetal thymus. Then, the DETC progenitors migrate to the epidermis with the guidance of selectins, CCR10, CCR4, etc. Eventually, mature DETCs proliferate and maintain a homeostatic population in the epidermis through IL-15 and aryl hydro-carbon receptor signaling. In "stressed" skin, DETCs are activated, exhibiting features such as a round morphology, cytotoxicity, and production of cytokines. In cutaneous carcinoma, DETCs generally inhibit tumor development directly in non-major histocompatibility complex-restricted manner, with the assistance of cytokines. DETCs also recognize and inhibit tumor via TCR, non-TCR receptors (such as 2B4 and NKG2D), or both. This study summarizes the biogenesis and the function of DETCs in cutaneous carcinoma and clarifies the essential surveillance role in the epidermis that DETCs play. As there are no DETCs in human epidermis but only human epidermis γδ T cells, we need to understand the anti-tumor pathways used by DETCs to find analogous immune pathways in human skin, which could be exploited for novel therapeutics.


Asunto(s)
Carcinoma/inmunología , Susceptibilidad a Enfermedades , Linfocitos Intraepiteliales/inmunología , Linfocitos Intraepiteliales/metabolismo , Neoplasias Cutáneas/inmunología , Animales , Carcinoma/metabolismo , Carcinoma/patología , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/inmunología , Transformación Celular Neoplásica/metabolismo , Humanos , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología
18.
Front Chem ; 7: 337, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31179266

RESUMEN

Permeation and separation efficiency of ceramic membranes are strongly dependent on their nanoporous structures, especially on the pore size. In this work, ultrasound is employed to form the size-controlled ZrO2 nanoparticles, and a ceramic membrane is prepared with tunable pore size. Under the ultrasound treatment, H+ from water plays a key role in the synthesis process. The cavitation caused by ultrasound promotes the hydrolysis of the precursor in water, which produces a large number of H+. These H+ will react with precipitant added and generate cyclic tetrameric units. Excess H+ can peptize cyclic tetrameric units and form an electrical double layer, resulting in a stable sol. Unlike ultrasound treatment, precipitant will react directly with the precursor and generate precipitation if there is no ultrasound added. Moreover, cavitation is good for the dispersion of cyclic tetrameric units. The particle size of Zr-based colloidal sol can be tuned in the ranges of 1.5 to 120 nm by altering the molar ratio of precursor to precipitant, ultrasonic power density and radiation time. Meanwhile, ultrasonic power density and radiation time have effects on grain size and the crystalline transition temperature of particles which influence performance of the ceramic membrane. As a result, membranes exhibit high performance together with high permeability and desirable rejection. To develop such a simple and controllable method for tuning particle size is extremely important in the preparation of nanoporous ceramic membranes.

19.
Artículo en Inglés | MEDLINE | ID: mdl-32038493

RESUMEN

Idiopathic central precocious puberty (ICPP) is a relatively common condition in preadolescent girls, and its pathogenesis remains to be uncovered. A variety of studies have highlighted the association of gut microbiota (GM) with endocrine diseases, such as obesity, which is commonly associated with ICPP. However, the relationship between GM and ICPP remains unexplored. Feces samples were collected from 25 girls with ICPP (ICPP group) and 23 healthy girls (Control group). We applied 16S rDNA sequencing to compare the GM between two groups. The ICPP group had higher GM diversity and was enriched for several GM species, including Ruminococcus gnavus, Ruminococcus callidus, Ruminococcus bromii, Roseburia inulinivorans, Coprococcus eutactus, Clostridium leptum, and Clostridium lactatifermentans, which are known to be associated with obesity and are related to the production of short-chain fatty acids. Additionally, 36 candidate GM biomarkers for patients with ICPP screening were identified with high accuracy (AUC = 0.95, 95% CI 0.88 to 1). We observed that the GM of the ICPP group was enriched for the microbial functions of cell motility, signal transduction, and environmental adaptation. Positive correlations were also detected between Fusobacterium and follicle-stimulating hormone, and Gemmiger and luteinizing hormone. This study documents relationships between GM and ICPP, and the implication of these findings remains to be determined.

20.
ACS Appl Mater Interfaces ; 10(21): 18093-18103, 2018 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-29732891

RESUMEN

Ultrasound (US) treatment coupled with membrane filtration has been utilized for membrane fouling control in water treatment; however, large-scale implementation of ultrasonic cleaning equipment appeared to be cost-prohibitive. In this study, a porous lead zirconate titanate (PZT) membrane is presented that enables in situ ultrasound generation by the application of an alternating voltage (AV) to mitigate fouling during oil-in-water (O/W) emulsion separation. We expect that this method is much more cost-effective because it is more direct, avoiding buildup of fouling and the need to take the membrane offline. Because the PZT membrane is hydrophilic, its underwater surface is oleophobic so that the accumulated oil droplets will have little affinity and hence can be removed easily by in situ-generated US. The effect of the in situ US generation on membrane fouling was investigated through variation in the excitation AV and its frequency, O/W emulsion pH, emulsified oil concentration, crossflow velocity, and transmembrane pressure. The results indicated that the in situ US generation resulted in a substantial decrease of fouling during the filtration process of O/W emulsions, whereas the membrane flux was maintained closely at its initial value.

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