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1.
Environ Res ; 214(Pt 2): 113837, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35810812

RESUMO

A furfural residue-derived activated carbon (AC) supported black-TiO2 photocatalyst was successfully prepared by ultrasonic-assisted sol-gel treatment (USG) and solvothermal treatment (ST) combined with microwave-assisted heating (MH). The prepared composites were characterized and evaluated based on the degradation of tetracycline hydrochloride (TC) under ultraviolet (UV) illumination. The average TiO2 nanoparticle size of the as-synthesized catalysts was between 9 and 11 nm. The bandgap of TiO2-USGM was 1.6 eV, much lower than that of other reference catalysts. Organic carbon and AC in the catalyst play positive roles in reducing the band gap (e.g. 1.6∼2.6 eV) and improving visible-light absorption. The oxygen vacancies are responsible for UV-visible absorption. Adding AC into black TiO2 resulted in a lower degree of recombination of photogenerated electrons. Mott-Schottky plots showed that AC-containing TiO2@AC-STM reduced the value of conduction band value from -0.59 eV to -0.24 eV, which is beneficial to photogenerated electrons. Compared with TiO2, the Ti-O-C and Ti-C- in TiO2@AC remarkably improved the adsorption and catalytic efficiency of TC. In a near-neutral pH environment, TiO2@AC-STM and TiO2@AC-USGM exhibited high removal efficiencies (88.0% and 75.7%, respectively) and degradation rates (0.0418 and 0.0302 µmol/g/s, respectively) at a catalyst load of 0.25 g/L. Notably, the catalyst can be effectively used over a wide range of pH (6-9). The solution pH after treatment was close to neutral, which is advantageous for wastewater treatment. The activation energies were found to be approximately 3.47 kJ/mol. The thermodynamic parameters showed that the photodegradation process was non-spontaneous and endothermic. Based on the trapping experiments, O2⋅- was mainly responsible for TC photodegradation over TiO2@AC-STM, followed by h+. The TC degradation pathways and catalyst stability were also investigated. Biomass-derived carbon-supported catalysts have great potential for waste biomass utilization as green, and low-cost catalysts.


Assuntos
Carvão Vegetal , Tetraciclina , Antibacterianos , Catálise , Carvão Vegetal/química , Calefação , Micro-Ondas , Fotólise , Titânio/química
2.
Sci Total Environ ; 838(Pt 2): 155412, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35569655

RESUMO

This study investigated the effect of temperature on pyrolysis of soapstock in a fluidized bed reactor, and the characterization of soapstock chars (SCs) and pyrolysis oils (POs) were analyzed. TGA, TG-FTIR, TG-MS, and Py-GCMS were employed to investigate characteristics of SS pyrolysis. Experimental results indicated that the yield of SC decreased with increasing temperature. Pyrolysis oil (PO) yield reached the maximum of 21.05 wt% at 600 °C and the yield of non-condensable gas varied with temperatures. The content of carbon, hydrogen and nitrogen distributed in the SC decreased with the increasing temperature, and sulfur tended to be retained in SC during pyrolysis with the distribution ratio of 0.55-0.62. Ketones, alcohols and hydrocarbons were the dominate substances in PO, and higher temperature promoted the production of short-chain alkanes and the conversion of alkenes to benzene derivatives. SS pyrolysis can be divided into three stages. Stage I was mainly the evaporation of free water and light organics in the raw material. Decomposition and conversion of organics mainly occurred at stage II. Stage III was the decomposition of CaCO3 and secondary cracking of residual organics. Ca2+ delayed the pyrolysis reaction of fatty acids and promoted decarboxylation which was the main deoxygenation pathway, and alkene production. This study provided a theoretical basis for the application of soapstock thermochemical treatment. It is of great significance for the quality improvement of PO and pollution control for pyrolysis processes.


Assuntos
Óleos de Plantas , Pirólise , Biocombustíveis , Temperatura Alta , Temperatura
3.
Hum Vaccin Immunother ; 18(1): 1-11, 2022 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-33689574

RESUMO

Neoantigens play a crucial role in cancer immunotherapy. However, the effectiveness and safety of neoantigen-based immunotherapies in patients with colorectal cancer (CRC), particularly in the Chinese population, have not been well studied. This study explored the feasibility and effectiveness of neoantigens in the treatment of CRC. Whole-exome sequencing (WES) and transcriptome sequencing were used to identify somatic mutations, RNA expression, and human leukocyte antigen (HLA) alleles. Neoantigen candidates were predicted, and immunogenicity was assessed. The neoantigens TSHZ3-L523P, RARA-R83H, TP53-R248W, EYA2-V333I, and NRAS-G12D from Patient 4 (PW4); TASP1-P161L, RAP1GAP-S215R, MOSPD1-V63I, and NAV2-D1973N from Patient 10 (PW10); and HAVCR2-F39V, SEC11A-R11L, SMPDL3B-T452M, LRFN3-R118Q, and ULK1-S248L from Patient 11 (HLA-A0201+PW11) induced a heightened neoantigen-reactive T cell (NRT) response as compared with the controls in peripheral blood lymphocytes (PBLs) isolated from patients with CRC. In addition, we identified neoantigen-containing peptides SEC11A-R11L and ULK1-S248L from HLA-A0201+PW11, which more effectively elicited specific CTL responses than the corresponding native peptides in PBLs isolated from HLA-A0201+PW11 as well as in HLA-A2.1/Kb transgenic mice. Importantly, adoptive transfer of NRTs induced by vaccination with two mutant peptides could effectively inhibit tumor growth in tumor-bearing mouse models. These data indicate that neoantigen-containing peptides with high immunogenicity represent promising candidates for peptide-mediated personalized therapy.Abbreviations: CRC: colorectal cancer; DCs: dendritic cells; ELISPOT: enzyme-linked immunosorbent spot; E:T: effector:target; HLA: human leukocyte antigen; MHC: major histocompatibility complex; Mut: mutant type; NGS: next-generation sequencing; NRTs: neoantigen-reactive T cells; PBMCs: peripheral blood mononuclear cells; STR: short tandem repeat; PBLs: peripheral blood lymphocytes; PBS: phosphate-buffered saline; PD-1: programmed cell death protein 1; TILs: tumor-infiltrating lymphocytes; RNA-seq: RNA sequencing; Tg: transgenic; TMGs: tandem minigenes; WES: whole-exome sequencing; WT: wild-type.


Assuntos
Neoplasias Colorretais , Linfócitos T , Animais , Antígenos de Neoplasias/uso terapêutico , Neoplasias Colorretais/terapia , Antígenos HLA , Antígenos de Histocompatibilidade Classe II/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Imunoterapia , Linfócitos do Interstício Tumoral , Camundongos , Peptídeo Hidrolases/metabolismo , Peptídeos , Esfingomielina Fosfodiesterase/metabolismo , Linfócitos T/imunologia
4.
Sci Total Environ ; 806(Pt 4): 150903, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653460

RESUMO

Co-pyrolysis of sophora wood (SW) and polyvinyl chloride (PVC) was conducted in a microwave reactor at different temperatures and different mixing ratios, and the transformation and distribution of chlorine in pyrolysis products were investigated. Microwave pyrolysis is a simple and efficient technique with better heating uniformity and process controllability than conventional heating. Compared with PVC pyrolysis, the addition of SW significantly reduced CO2 yield and greatly increased the yield of CO. The yield and quality of pyrolysis oil were effectively improved by SW, and the content of chlorine-containing compounds in the oil was suppressed to <1% at low temperatures (<550 °C). Co-pyrolysis of SW and PVC reduced the chlorine emissions from 59.07% to 28.09% and promoted the retention of chlorine in char (from 0.33% to 4.72%). Cellulose, hemicellulose, and lignin were co-pyrolyzed with PVC to investigate their effects on chlorine distribution. The experiments demonstrated that lignin had the most significant effects on reducing gas phase chlorine emission and achieving chlorine immobilization, and chlorine mainly existed in the form of sodium chloride in the char of lignin-PVC co-pyrolysis. Hence co-pyrolysis of lignocellulosic biomass and PVC provides a practical pathway for utilization of PVC waste in an environmentally friendly manner, realizing efficient chlorine retention and significantly reducing chlorine-related emissions.


Assuntos
Cloreto de Polivinila , Pirólise , Biomassa , Cloro , Temperatura Alta , Micro-Ondas
5.
Sci Total Environ ; 815: 152303, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896502

RESUMO

This study explored pyrolysis characteristics, nitrogen transformation and migration of heavy metals during microwave-assisted pyrolysis of municipal sewage sludge in a continuously operated auger pyrolyser at different temperatures and corn straw ratios. The results showed higher temperatures and more corn straw resulted in more gas yield (e.g., CO2, CO, CH4 and H2) and less char yield. 5 wt% corn straw addition at 750 °C achieved high-quality bio-oil with less O-containing compounds, which was more favorable for upgrading to transportation fuels. Sludge chars prepared at higher corn straw ratios had lower ratios of H/C and N/C, and higher carbon content. Nitrogen transformation pathways and mechanisms were investigated. The residual ratio of heavy metals (except Cd) in sludge char was 67.74-100%. However, the residual ratio of Cd decreased significantly to 6.46% at 750 °C. Concentrations of all heavy metals in sludge char conformed to national standard (CJ/T 362-2011, China), and the potential ecological risk was slight. Sludge chars prepared in the presence of corn straw had lower ecological risk and higher retention capacity of heavy metals (e.g., Pb, Cr, Mn, Cu, Zn, and Ni) compared with pyrolysis of sewage sludge.


Assuntos
Metais Pesados , Pirólise , Micro-Ondas , Nitrogênio , Esgotos , Zea mays
6.
Comput Intell Neurosci ; 2021: 9945044, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956359

RESUMO

Developing artificial intelligence (AI) agents is challenging for efficient exploration in visually rich and complex environments. In this study, we formulate the exploration question as a reinforcement learning problem and rely on intrinsic motivation to guide exploration behavior. Such intrinsic motivation is driven by curiosity and is calculated based on episode memory. To distribute the intrinsic motivation, we use a count-based method and temporal distance to generate it synchronously. We tested our approach in 3D maze-like environments and validated its performance in exploration tasks through extensive experiments. The experimental results show that our agent can learn exploration ability from raw sensory input and accomplish autonomous exploration across different mazes. In addition, the learned policy is not biased by stochastic objects. We also analyze the effects of different training methods and driving forces on exploration policy.


Assuntos
Inteligência Artificial , Motivação , Comportamento Exploratório , Aprendizagem , Reforço Psicológico
7.
J Healthc Eng ; 2021: 5607999, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745501

RESUMO

Physiological studies have shown that the hippocampal structure of rats develops at different stages, in which the place cells continue to develop during the whole juvenile period of rats and mature after the juvenile period. As the main information source of place cells, grid cells should mature earlier than place cells. In order to make better use of the biological information exhibited by the rat brain hippocampus in the environment, we propose a position cognition model based on the spatial cell development mechanism of rat hippocampus. The model uses a recurrent neural network with parametric bias (RNNPB) to simulate changes in the discharge characteristics during the development of a single stripe cell. The oscillatory interference mechanism is able to fuse the developing stripe waves, thus indirectly simulating the developmental process of the grid cells. The output of the grid cells is then used as the information input of the place cells, whose development process is simulated by BP neural network. After the place cells matured, the position matrix generated by the place cell group was used to realize the position cognition of rats in a given spatial region. The experimental results show that this model can simulate the development process of grid cells and place cells, and it can realize high precision positioning in the given space area. Moreover, the experimental effect of cognitive map construction using this model is basically consistent with the effect of RatSLAM, which verifies the validity and accuracy of the model.


Assuntos
Hipocampo , Modelos Neurológicos , Animais , Cognição , Redes Neurais de Computação , Ratos
8.
J Hazard Mater ; 416: 125887, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492825

RESUMO

The effects of temperature and power on product distribution and characteristics of oily sludge (OS) pyrolysis were investigated in a microwave reactor. The maximum oil yield was 72.55 wt% at 550 °C and 71.47 wt% at 800 W, respectively. X-ray photoelectron spectroscopy (XPS) indicated that C-C and C-O were the main forms of carbon in OS char (OC). The sulfur (S) content in OC increased as the temperature/power rose, implying that S might exist in the form of inorganics or OC had S retention ability. In temperature control mode, the changes of functional groups on OC surface were more sensitive. The maximum hydrocarbon content in oil was 14.56% at 350 °C and 13.40% at 900 W, respectively. The contents of oxygenated compounds and heterocycles in oil from temperature control mode were higher. The CO yield increased with increasing temperature/power, reaching the maximum of 9.60 wt% at 650 °C and 7.75 wt% at 900 W, respectively. Compared with power control mode, it seemed that more heavy metals (HMs) were retained in OC in temperature control mode. The Er of HMs were at the clean level and RI indicated the HMs in OC had a low environmental risk.


Assuntos
Metais Pesados , Pirólise , Micro-Ondas , Esgotos , Temperatura
9.
Clin Lab ; 67(8)2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34383427

RESUMO

BACKGROUND: Gastric cancer (GC) remains the fourth-leading malignancy worldwide and has a high mortality rate. Accumulating evidence reveals that long noncoding RNAs (lncRNAs) play essential roles in tumorigenesis and metastasis and can be used as potential biomarkers for diagnosis and prognosis. METHODS: We downloaded gene expression profiles from the National Center of Biotechnology Information Gene Expression Omnibus (GEO), screened lncRNAs differentially expressed in gastric cancer tissues and adjacent tissues, and then constructed a lncRNA-miRNA-mRNA network. Seventy patients with gastric cancer were divided into two groups according to different clinical characteristics. The expression of lncRNA LUCAT1 in gastric cancer was detected by reverse transcription polymerase chain reaction (RT-PCR). The AGS and SGC-7901 cell lines were used in CCK8 assay, apoptosis, cell cycle test, transwell assay, and wound healing assay. RESULTS: The expression level of LUCAT1 was associated with tumor diameter (p < 0.001), tissue differentiation grade (p = 0.026), and LNM status (p = 0.020) in GC. The results showed that the lncRNA LUCAT1 could promote the proliferation, invasion, and migration of GC cells, inhibit the apoptosis of GC cells, and affect the process of cell cycles. CONCLUSIONS: The lncRNA LUCAT1 may be used as a potential biomarker for early signs of LNM in GC and may play a crucial role in the development of GC.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias Gástricas , Biomarcadores , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética
10.
Oncol Rep ; 41(6): 3424-3434, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31002357

RESUMO

Several studies have demonstrated that calpain­1 is involved in a variety of pathophysiological processes, including tumorigenesis. However, the clinical relevance and role of calpain­1 in colorectal cancer (CRC) are unclear. Filamin A (FLNA) is an actin­binding protein that participates in cancer progression and can be cleaved by calpain­1. In the present study, the protein expression levels of calpain­1 and FLNA were detected by immunohistochemistry in 467 matched cancerous and paracancerous tissues from patients with CRC. The staining results and the clinicopathological characteristics of the patients were comprehensively analyzed. A high expression level of calpain­1 was strongly associated with age, metastasis, Dukes stage and survival time but not with sex, histologic grade, tumour location or tumor size. By contrast, a low expression level of FLNA was significantly associated with tumor size, histological grade, metastasis, Dukes stage and survival time, but not with age, sex, or tumor location. Kaplan­Meier survival analysis demonstrated that patients with calpain­1 overexpression had a shorter mean overall survival (OS) than patients with lower levels of calpain­1 expression. Unlike high levels of calpain­1, high levels of FLNA were associated with longer OS than lower levels of FLNA expression. Furthermore, calpain­1 expression was inversely correlated with FLNA expression. The relationship between calpain­1 and FLNA was further confirmed using CRC cell lines in vitro. When calpain­1 expression decreased in CRC cells, FLNA expression increased. Furthermore, calpain­1 knockdown in CRC cells resulted in decreased proliferation, colony formation, migration and invasion. The present findings suggest that calpain­1 overexpression predicted a poor outcome in patients with CRC and promoted tumor progression, possibly via FLNA downregulation.


Assuntos
Biomarcadores Tumorais/genética , Calpaína/genética , Neoplasias Colorretais/genética , Filaminas/genética , Idoso , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/patologia , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia
11.
Micromachines (Basel) ; 8(8)2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30400427

RESUMO

3D printing has emerged as one of the modern tissue engineering techniques that could potentially form scaffolds (with or without cells), which is useful in treating cardiovascular diseases. This technology has attracted extensive attention due to its possibility of curing disease in tissue engineering and organ regeneration. In this paper, we have developed a novel rotary forming device, prepared an alginate⁻gelatin solution for the fabrication of vessel-like structures, and further proposed a theoretical model to analyze the parameters of motion synchronization. Using this rotary forming device, we firstly establish a theoretical model to analyze the thickness under the different nozzle extrusion speeds, nozzle speeds, and servo motor speeds. Secondly, the experiments with alginate⁻gelatin solution are carried out to construct the vessel-like structures under all sorts of conditions. The experiment results show that the thickness cannot be adequately predicted by the theoretical model and the thickness can be controlled by changing the parameters. Finally, the optimized parameters of thickness have been adjusted to estimate the real thickness in 3D printing.

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