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1.
Bioresour Technol ; 330: 124965, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33735725

RESUMEN

With the increasing of data in wastewater treatment, data-driven machine learning models are useful for modeling biological processes and complex reactions. However, few data-driven models have been developed for simulating the microbial electrolysis cells (MECs) and traditional models are too ambiguous to comprehend the mechanisms. In this study, a new general data-driven two-stage model was firstly developed to predict CH4 production from in-situ biogas upgrading in the biocathode MECs via direct electron transfer (DET), named NARX-BP hybrid neural networks. Compared with traditional one-stage model, the model could well predict methane production via DET with excellent performance (all R2 and MES of 0.918 and 6.52 × 10-2, respectively) and reveal the mechanisms of biogas upgrading, for the new systematical modeling approach could improve the versatility and applicability by inputting significant intermediate variables. In addition, the model is generally available to support long-term prediction and optimal operation for anaerobic digestion or complex MEC systems.


Asunto(s)
Biocombustibles , Metano , Anaerobiosis , Reactores Biológicos , Electrólisis , Electrones , Aprendizaje Automático , Redes Neurales de la Computación
2.
Water Res ; 197: 117055, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33789202

RESUMEN

Biogas produced from anaerobic digestion usually contains 30%-50% CO2, much of which must be removed, before utilization. Bioelectrochemical biogas upgrading approaches show promise, however, they have not yet been optimized for practical applications. In this study, a bioelectrochemical system with low energy input (applied cathode potential of -0.5 V vs. standard hydrogen electrode, SHE) was used for in-situ biogas upgrading. High efficiency CO2 conversion (318.5 mol/d/m2) was achieved when the system was operated with an organic load of 1.7 kgCOD/(m3 d). Methane content in the upgraded biogas was 97.0% and CO2 concentrations stayed below 3%, which is comparable to biogas upgraded with more expensive and less sustainable physiochemical approaches. The high efficiency of this approach could likely be attributed to a significant enrichment of Methanothrix (92.7%) species on the cathode surface that were expressing genes involved in both acetogenic methanogenesis and direct electron transfer (DET). Electromethanogenesis by these organisms also increased proton consumption and created a higher pH that increased the solubility of CO2 in the bioreactor. In addition, CO2 removal from the biogas was likely further enhanced by an enrichment of Actinobacillus species known to be capable of CO2 fixation. Artificial neural network (ANN) models were also used to estimate CH4 production under different loading conditions. The ANN architecture with 10 neurons at hidden layers fit best with a mean square error of 6.06 × 10-3 and R2 of 0.99.


Asunto(s)
Biocombustibles , Metano , Reactores Biológicos , Dióxido de Carbono , Electrodos , Methanosarcinaceae
3.
Artículo en Inglés | MEDLINE | ID: mdl-33661026

RESUMEN

Objective: To compare the effectiveness of tranexamic acid (TXA) in reducing blood loss and decreasing surgery duration in craniomaxillofacial surgery. Methods: The literature was searched systematically for all comparative studies of the effect of TXA on craniomaxillofacial surgery with placebo to evaluate the efficacy of TXA in craniomaxillofacial surgery. The primary outcome was intraoperative blood loss, and secondary outcomes were postoperative hematocrit, postoperative hemoglobin, and operation duration. Results: This systematic review included 16 studies consisting of 958 patients. Meta-analysis revealed that compared with the placebo group, the TXA group showed a significant reduction in intraoperative blood loss of 139.81 mL (95% confidence interval, CI: -179.66 to -99.96 mL; p < 0.01), a shortening of the maxillary surgery duration of 15.48 min (95% CI: -21.03 to -9.92 min; p < 0.01), an elevation of the postoperative hemoglobin level of 0.74 mg/dL (95% CI: 0.42 to 1.07 mg/dL; p < 0.01), and a limited effect on increasing the postoperative hematocrit level of 1.77% (95% CI: 0.17 to 3.36; p = 0.03). Conclusion: The use of TXA in craniomaxillofacial surgery can effectively reduce intraoperative blood loss, maintain elevate postoperative hemoglobin and hematocrit levels, and reduce the operation duration.

4.
Medicine (Baltimore) ; 100(5): e24284, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33592872

RESUMEN

BACKGROUND: Head and neck melanomas (HNMs) behave differently from cutaneous melanomas in other sites, and the efficacy of sentinel lymph node biopsy (SLNB) for patients with HNMs remains controversial. METHODS: Studies on prognosis following SLNB were included. The prognostic role of SLNB and other potential predictors were analyzed using pooled relative risk (RR) or hazard ratio (HR). RESULTS: Pooled statistics showed that SLNB improved overall survival of HNMs patients (HR = 0.845; 95% CI: 0.725-0.986; P = .032). The positive status of SN was proved as a risk factor of poor prognosis in HNMs (HR = 3.416; 95% CI: 1.939-6.021; P < .001). SLNB did not have significant correlation with lower recurrences (RR = .794; 95% CI: 0.607-1.038; P = .091). CONCLUSIONS: SLNB is associated with better overall survival and the SN status is a promising risk factor of poor prognosis for HNMs patients.


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Melanoma/patología , Biopsia del Ganglio Linfático Centinela/métodos , Neoplasias Cutáneas/patología , Humanos , Pronóstico , Medición de Riesgo/métodos
6.
Environ Res ; 189: 109884, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32678736

RESUMEN

Biological treatment of high salinity organic wastewater is a significant challenge because many microorganisms involved in the anaerobic digestion process cannot survive high osmotic pressures. In order to alleviate some of the stresses associated with the treatment of high salinity wastewater, two lab-scale up-flow anaerobic sludge bed reactors with or without magnetite (100 g/L) were used to treat high salinity organic wastewater. This study showed that the bioreactor amended with magnetite had higher chemical oxygen demand removal efficiencies (90.2% ± 0.54% vs 73.1% ± 1.9%) and methane production rates (4082 ± 334 ml (standard temperature and atmospheric pressure, STP)/d vs 2640 ± 120 ml (STP)/d) than the non-amended control reactor. In addition, the consumption of volatile fatty acids (20.9 ± 3.4 mM vs 61.7 ± 2.0 mM) was accelerated. Microbial community analysis revealed that the addition of magnetite caused the enrichment of many bacterial genera known to form robust biofilms (i.e. Pseudomonas) that are also capable of extracellular electron transfer and methanogens from the genus Methanosarcina which have been shown to participate in direct interspecies electron transfer. These results show that magnetite addition could enhance the performance of anaerobic digesters treating high salinity wastewater.

7.
Langmuir ; 36(21): 6017-6024, 2020 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-32436708

RESUMEN

Cesium lead halide perovskite nanocrystals (CLHP NCs) have drawn considerable attention because of their promising optoelectrical properties. However, owing to the extreme vulnerability of CLHP NCs to water and polar alcohols, until now most synthesis approaches inevitably adopted ecounfriendly solvents. It is still a challenge to employ green polar alcohol (ethanol) as a solvent to synthesize CLHP NCs. In this work, we realized the room-temperature in situ synthesis of CsPbBr3/SiO2 sol entirely in ethanol by innovatively constructing amine-functionalized silica micelles, which originated from the synergistic effect of 3-aminopropyltriethoxysilane and tetraethylorthosilicate (TEOS) during an acid-catalyzed sol-gel process. The sol exhibited high stability and an absolute photoluminescence quantum yield of 61.9% in ethanol without a further modification process. The light-emitting intensity of the sol preserved for 34 days merely declined to 62.1%. This work sheds light on the less common strategy of directly synthesizing CsPbBr3 NCs and long-term stable preservation in a strongly polar solvent.

8.
J Surg Res ; 254: 102-109, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32422429

RESUMEN

BACKGROUND: Wound healing is a complex process aiming at repairing the damaged skin. MiR-23b has been reported to be upregulated during wound healing. In this study, we intended to explore the working mechanism of miR-23b during wound healing. METHODS: Quantitative real-time polymerase chain reaction was performed to detect the enrichment of miR-23b and tissue inhibitor of metalloproteinase-3 (TIMP3) in HaCaT cells. Scratch wound assay was carried out to measure the migration of HaCaT cells. The target of miR-23b was predicted by microT-CDS software, and the combination was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation assay. The abundance of TIMP3 protein was detected by Western blot assay. RESULTS: The abundance of miR-23b was positively related to the concentration and time of transforming growth factor ß1 treatment in HaCaT cells. MiR-23b promoted the migration of keratinocytes. TIMP3 was a direct target of miR-23b and was negatively regulated by miR-23b. TIMP3 inhibited the migration of keratinocytes. MiR-23b accelerated the migration of keratinocytes by downregulating the abundance of TIMP3. CONCLUSIONS: MiR-23b promoted the migration of keratinocytes partly through reducing the enrichment of TIMP3. MiR-23b might be a promising target for the treatment of wound healing-associated diseases.


Asunto(s)
Movimiento Celular/genética , Regulación hacia Abajo/genética , Queratinocitos/fisiología , MicroARNs/fisiología , Inhibidor Tisular de Metaloproteinasa-3/genética , Línea Celular , Movimiento Celular/fisiología , Queratinocitos/química , MicroARNs/análisis , Inhibidor Tisular de Metaloproteinasa-3/análisis , Transfección , Factor de Crecimiento Transformador beta1/farmacología , Cicatrización de Heridas/genética
9.
Langmuir ; 36(13): 3565-3572, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32183518

RESUMEN

Cesium lead halide perovskite nanocrystals (CLHP NCs) have drawn considerable attention because of their promising optoelectrical properties. However, owing to extreme vulnerability of CLHP NCs to water and polar alcohols, up to date, most of the synthesis approaches have inevitably adopted eco-unfriendly solvents. It is still a big challenge to employ green polar alcohol (ethanol) as a solvent to synthesize CLHP NCs. In this work, we realized a room-temperature in situ synthesis of CsPbBr3/SiO2 sol entirely in ethanol by innovatively constructing amine-functionalized silica micelles, which is originated from the synergistic effect of 3-aminopropyltriethoxysilane and tetraethyl orthosilicate (TEOS) during an acid-catalyzed sol-gel process. The sol exhibited high stability and an absolute photoluminescence quantum yield of 61.9% in ethanol without a further modification process. The light emitting intensity of the sol preserved for 34 days merely declined to 62.1%. This work sheds light on the less common strategy of directly synthesizing CsPbBr3 NCs and long-term stable preservation in a strong polar solvent.

11.
Bioresour Technol ; 291: 121877, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31376672

RESUMEN

Bioelectrochemical conversion of CO2 to CH4 is a promising way to increase the calorific value of biogas produced during anaerobic digestion. There are two groups of methanogens enriched in these systems, hydrogenotrophs and acetoclastic methanogens that can also directly accept electrons from an electrode or another microorganism. In this study, a microbial electrolysis cell (MEC) poised at -500 mV (vs. SHE) was operated for biogas upgrading. Methane content in the biogas increased from 71% to >90%, and 8.2% of the CO2 was converted to methane. Methanothrix, an acetoclastic methanogen that can participate in direct electron transfer (DET), and Azonexus, an acetate-oxidizing electrogen, were enriched on the cathode. Transcriptomics revealed that Methanothrix on the cathode were using the CO2 reduction pathway, while Methanothrix in the bulk sludge were using the acetate decarboxylation pathway for production of methane. These results show that stimulation of DET in MEC enhances biogas-upgrading processes.


Asunto(s)
Biocombustibles , Methanosarcinaceae , Electrodos , Electrólisis , Transporte de Electrón , Electrones , Metano/metabolismo , Aguas del Alcantarillado
12.
Water Res ; 161: 570-580, 2019 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-31238222

RESUMEN

The raw fresh leachate from municipal solid waste (MSW) incineration plants contains high concentrations of volatile fatty acids (VFAs), ammonia and metals, all compounds that severely limit anaerobic digestion treatment efficiencies. These inhibitory compounds make reactor systems unstable, causing reactor start-up periods to take more than 100 days, even when the leachate is diluted significantly. In this study, granular activated carbon (GAC) was incorporated into a bioreactor fed with raw incineration leachate. Addition of GAC allowed direct treatment of raw incineration leachate without any start-up acclimation period, while the non-amended control reactor soured immediately and collapsed within 17 days. When hydraulic retention time (HRT) of the GAC-amended reactor was stepwise decreased to increase organic loading rates (OLR) to 25.0 kgCOD/(m3·d), COD removal efficiencies remained stable at >90%. Metagenomic analysis of the GAC-amended reactor revealed that Geobacter and Methanosarcina, species known to participate in direct interspecies electron transfer (DIET), were more abundant in the GAC-amended reactor than the seed sludge. In addition, the abundance of genes coding for proteins thought to be involved in DIET such as electrically conductive pili and the outer membrane c-type cytochrome, OmcS, increased significantly, while genes involved in fermentation, and nitrate (narG) and sulfate (dsrA) reduction dropped significantly as the experiment progressed. These results are significant because this is the first detailed investigation into the metabolic capabilities of microbial communities involved in efficient treatment of raw incineration leachate within biomethanogenic reactors that did not require a long start-up period.


Asunto(s)
Carbón Orgánico , Incineración , Anaerobiosis , Reactores Biológicos , Electrones , Metano , Aguas del Alcantarillado
13.
Materials (Basel) ; 12(9)2019 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-31072020

RESUMEN

In recent years, all-inorganic lead-halide perovskites have received extensive attention due to their many advantages, but their poor stability and high toxicity are two major problems. In this paper, a low toxicity and stable Cs2SnCl6 double perovskite crystals were prepared by aqueous phase precipitation method using SnCl2 as precursor. By the XRD, ICP-AES, XPS, photoluminescence and absorption spectra, the fluorescence decay curve, the structure and photoluminescence characteristics of Ce3+-doped and undoped samples have been investigated in detail. The results show that the photoluminescence originates from defects. [ S n S n 4 + 2 + +VCl] defect complex in the crystal is formed by Sn2+ substituting Sn4+. The number of defects formed by Sn2+ in the crystal decreases with Ce3+ content increases. Within a certain number of defects, the crystal luminescence is enhanced with the number of [ S n S n 4 + 2 + +VCl] decreased. When Ce3+ is incorporated into the crystals, the defects of [ C e 3 + S n 4 + +VCl] and [ S n S n 4 + 2 + +VCl] were formed and the crystal show the strongest emission. This provides a route to enhance the photoluminescence of Cs2SnCl6 double perovskite crystals.

14.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(3): 332-336, 2019 Mar 15.
Artículo en Chino | MEDLINE | ID: mdl-30874391

RESUMEN

Objective: To summarize clinical experience and curative effect in applying three-dimensional mechanical equilibrium concept to cartilage scaffold construction in total auricular reconstruction. Methods: Between June 2015 and June 2017, ninety-seven microtia patients (102 ears) were treated with total ear reconstruction by using tissue expanders. The patients included 43 males and 54 females and their age ranged from 7 to 45 years with an average of 14 years. There were 92 unilateral cases (45 in left side and 47 in right side) and 5 bilateral ones. There were 89 congenital cases and 8 secondary cases. According to microtia classification criteria, there were 21 cases of type Ⅱ, 67 cases of type Ⅲ, and 9 cases of type Ⅳ. Tissue expander was implanted in the first stage. In the second stage, autogenous cartilage was used to construct scaffolds which were covered by enlarged flap. According to the three-dimensional mechanical equilibrium concept, the stable ear scaffold was supported by the scaffolds base, the junction of helix and inferior crura of antihelix, and helix rim. The reconstructed ears were repaired in the third stage operation. Results: All patients had undergone ear reconstruction successfully and all incisions healed well. No infection, subcutaneous effusion, or hemorrhage occurred after operation. All skin flaps, grafts, and ear scaffolds survived completely. All patients received 5- to 17-month follow-up time (mean, 11.3 months) and follow-up time was more than 12 months in 61 cases (64 ears). All reconstructed ears stood upright, and subunits structure and sensory localization of reconstructed ears were clear, and the position, shape, size, and height of bilateral ears were basically symmetrical. Mastoid region scar hyperplasia occurred in 3 patients, which was relieved by anti-scar drugs injection. No scaffolds exposure, absorption, or structural deformation occurred during follow-up period. Conclusion: Application of three-dimensional mechanical equilibrium concept in cartilage scaffold construction can reduce the dosage of costal cartilage, obtain more stable scaffold, and acquire better aesthetic outcomes.


Asunto(s)
Microtia Congénita , Oído Externo , Procedimientos Quirúrgicos Reconstructivos , Adolescente , Adulto , Cartílago , Niño , Microtia Congénita/cirugía , Oído Externo/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Colgajos Quirúrgicos , Expansión de Tejido , Adulto Joven
15.
Plast Reconstr Surg ; 143(3): 711-721, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30601325

RESUMEN

BACKGROUND: Choosing implant shape (round or anatomical) is one of the most essential yet controversial decisions in cosmetic breast augmentation. Many surgeons choose implant shape based on personal experience or expert opinion. This is the first systematic review and meta-analysis comparing the aesthetic effect between anatomical and round implants in primary cosmetic breast augmentation. METHODS: The authors searched the PubMed, MEDLINE, Embase, ScienceDirect, Web of Knowledge, Scopus, and Cochrane Central Register of Controlled Trials databases for studies that compared anatomical and round implants in primary cosmetic breast augmentation. Primary outcomes were postoperative aesthetic effect and correct identification rate of implant shape. Random effects models were used to obtain pooled standardized mean difference and 95 percent confidence intervals. RESULTS: One randomized comparative and four observational comparative studies met the inclusion criteria. No aesthetic superiority was found in the anatomical implant group with regard to overall appearance (standardized mean difference, 0.06; 95 percent CI, -0.40 to 0.53), naturalness (standardized mean difference, 0.18; 95 percent CI, -1.51 to 1.15), projection, upper pole contour, and lower pole contour. Pooled correct identification rate of implant shape by plastic surgeons was 52 percent (95 percent CI, 0.46 to 0.58). CONCLUSIONS: Generally, anatomical implants do not seem to have an aesthetic superiority compared to round implants. Plastic surgeons seemed to be unable to accurately differentiate the two implant shapes in vivo. Further studies should focus on identifying the specific indications for the use of anatomical implants.


Asunto(s)
Implantación de Mama/instrumentación , Implantes de Mama , Mama/anatomía & histología , Estética , Mama/cirugía , Implantación de Mama/métodos , Femenino , Humanos , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
Micromachines (Basel) ; 10(1)2018 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-30597958

RESUMEN

A 3D printed force sensor with a composite structure developed by combining digital light processing (DLP) based printing and inkjet printing technologies is described in this paper. The sensor has cost effectiveness and time-saving advantages compared to the traditional sensor manufacturing process. During this work, the substrate of the force sensor was printed by a DLP based 3D printer using a transparent high-temperature resin, and the strain gauge of the force sensor was inkjet printed using poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT/PSS) conductive ink. Finite element (FE) simulation was conducted to find the print origin of the strain gauge. The relationship between the mechanical properties of the post-cured resin and the curing time was investigated and the resistance of the printed strain gauges was characterized to optimize process parameters. Afterward, the force sensor was characterized. Experimental results show that the sensitivity of the sensor is 2.92% N-1 and the linearity error is 3.1485% full scale (FS) within the range from 0 mN⁻160 mN, and the effective gauge factor of the strain gauge is about 0.98. The resistance drifting is less than 0.004 kΩ within an hour. These figures prove that the device can perform as a force sensor and 3D printing technology may have great applied potential in sensor fabrication.

17.
Medicine (Baltimore) ; 95(31): e4250, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27495029

RESUMEN

Primary gastric lymphoma (PGL) is the most common extranodal non-Hodgkin lymphoma. This retrospective study aimed to analyze the clinical characteristics, prognostic factors, and roles of different treatment modalities in patients with PGL.From January 2003 to November 2014, 165 patients who were diagnosed with PGL at West China Hospital were enrolled in this study. The clinical features, treatment, and follow-up information were analyzed.In this study, diffuse large B-cell lymphoma (DLBCL) (108, 65.5%) and mucosa-associated lymphoid tissue (MALT) lymphoma (52, 31.5%) were two predominant histological subtypes. One-year and 5-year overall survival (OS) rates of all patients were 95.2% and 79.5%, respectively; in whom 110 (66.7%) underwent surgery, 110 (66.7%) received chemotherapy, 12 (7.3%) received radiotherapy, and 10 (6.1%) received Helicobacter pylori eradication. And 75 patients (45.5%) were treated with at least 2 different types of therapies. Elevated lactic dehydrogenase (LDH) levels, poor performance status (PS), advanced stage, International Prognostic Index (IPI) score ≥3, conservative treatment, and high-grade histological subtype were associated with worse prognosis in univariate analysis. Cox regression analysis showed that LDH levels, PS, staging, and histological subtype were independent predictors of survival outcomes. In the DLBCL type, 5-year OS was significantly better in the surgically treated group (80.1%) than that of patients conservatively treated (49.8%) (P = 0.001). Surgical treatment had almost no impact on OS in the MALT type than conservative treatment (P = 0.597). The proportion of patients received conservative treatment increased from 4.5% in period 1 to 51.7% in period 4.High LDH levels, poor PS, advanced staging, and malignant pathological type at diagnosis are significantly associated with poor OS. Our data suggest that surgery is superior in prognosis over conservative treatment in the DLBCL type, but not in the MALT type. Recently, conservative treatment is becoming more preferred approach in patients with PGL.


Asunto(s)
Causas de Muerte , Linfoma de Células B Grandes Difuso/mortalidad , Linfoma de Células B Grandes Difuso/patología , Linfoma no Hodgkin/mortalidad , Linfoma no Hodgkin/patología , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Biopsia con Aguja , Estudios de Cohortes , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Linfoma de Células B de la Zona Marginal/mortalidad , Linfoma de Células B de la Zona Marginal/patología , Linfoma de Células B de la Zona Marginal/terapia , Linfoma de Células B Grandes Difuso/terapia , Linfoma no Hodgkin/terapia , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Radioterapia Ayuvante , Estudios Retrospectivos , Medición de Riesgo , Neoplasias Gástricas/terapia , Análisis de Supervivencia , Adulto Joven
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