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1.
Opt Lett ; 48(10): 2571-2574, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37186711

RESUMEN

Two-dimensional (2D) antiferromagnetic semiconductor chromium thiophosphate (CrPS4) has gradually become a major candidate material for low-dimensional nanoelectromechanical devices due to its remarkable structural, photoelectric characteristics and potentially magnetic properties. Here, we report the experimental study of a new few-layer CrPS4 nanomechanical resonator demonstrating excellent vibration characteristics through the laser interferometry system, including the uniqueness of resonant mode, the ability to work at the very high frequency, and gate tuning. In addition, we demonstrate that the magnetic phase transition of CrPS4 strips can be effectively detected by temperature-regulated resonant frequencies, which proves the coupling between magnetic phase and mechanical vibration. We believe that our findings will promote the further research and applications of the resonator for 2D magnetic materials in the field of optical/mechanical signal sensing and precision measurement.

2.
Opt Lett ; 48(1): 81-84, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36563374

RESUMEN

Bolometers based on graphene have demonstrated outstanding performance with high sensitivity and short response time. In situ adjustment of bolometers is very important in various applications, but it is still difficult to implement in many systems. Here we propose a gate-tunable bolometer based on two strongly coupled graphene nanomechanical resonators. Both resonators are exposed to the same light field, and we can measure the properties of one bolometer by directly tracking the resonance frequency shifts, and indirectly measure the other bolometer through mechanical coupling. We find that the sensitivity and the response bandwidth of both bolometers can be independently adjusted by tuning the corresponding gate voltages. Moreover, the properties of the indirectly measured bolometer show a dependence on the coupling between the two resonators, with other parameters being fixed. Our method has the potential to optimize the design of large-scale bolometer arrays, and open new horizons in infrared/terahertz astronomy and communication systems.

3.
Appl Microbiol Biotechnol ; 107(23): 7197-7211, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37741939

RESUMEN

Tetanus toxin (TeNT) and botulinum neurotoxins (BoNTs) are neuroprotein toxins, with the latter being the most toxic known protein. They are structurally similar and contain three functional domains: an N-terminal catalytic domain (light chain), an internal heavy-chain translocation domain (HN domain), and a C-terminal heavy chain receptor binding domain (Hc domain or RBD). In this study, fusion functional domain molecules consisting of the TeNT RBD (THc) and the BoNT/A RBD (AHc) (i.e., THc-Linker-AHc and AHc-Linker-THc) were designed, prepared, and identified. The interaction of each Hc domain and the ganglioside receptor (GT1b) or the receptor synaptic vesicle glycoprotein 2 (SV2) was explored in vitro. Their immune response characteristics and protective efficacy were investigated in animal models. The recombinant THc-linker-AHc and AHc-linker-THc proteins with the binding activity had the correct size and structure, thus representing novel subunit vaccines. THc-linker-AHc and AHc-linker-THc induced high levels of specific neutralizing antibodies, and showed strong immune protective efficacy against both toxins. The high antibody titers against the two novel fusion domain molecules and against individual THc and AHc suggested that the THc and AHc domains, as antigens in the fusion functional domain molecules, do not interact with each other and retain their full key epitopes responsible for inducing neutralizing antibodies. Thus, the recombinant THc-linker-AHc and AHc-linker-THc molecules are strong and effective bivalent biotoxin vaccines, protecting against two biotoxins simultaneously. Our experimental design will be valuable to develop recombinant double-RBD fusion molecules as potent bivalent subunit vaccines against bio-toxins. KEY POINTS: • Double-RBD fusion molecules from two toxins had the correct structure and activity. • THc-linker-AHc and AHc-linker-THc efficiently protected against both biotoxins. • Such bivalent biotoxin vaccines based on the RBD are a valuable experimental design.


Asunto(s)
Toxinas Botulínicas Tipo A , Toxina Tetánica , Animales , Toxina Tetánica/genética , Toxina Tetánica/metabolismo , Toxinas Botulínicas Tipo A/genética , Toxinas Botulínicas Tipo A/metabolismo , Unión Proteica , Anticuerpos Neutralizantes , Vacunas de Subunidad/genética
4.
Anaerobe ; 82: 102764, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37479022

RESUMEN

OBJECTIVES: The mature botulinum neurotoxin (BoNT) is a long peptide chain consisting of a light chain (L) and a heavy chain (H) linked by a disulfide bond, where the heavy chain is divided into a translocation domain and an acceptor binding domain (Hc). In this study, we further explored the biology activity and characteristics of recombinant L-HN fragment (EL-HN) composed of the L and HN domains of BoNT/E in vivo and in vitro. METHODS: Neurotoxicity of L-HN fragments from botulinum neurotoxins was assessed in mice. Cleavage of dichain EL-HN in vitro and in neuro-2a cells was assessed and compared with that of single chain EL-HN. Interaction of HN domain and the receptor synaptic vesicle glycoprotein 2C (SV2C) was explored in vitro and in neuro-2a cells only expressing SV2C. RESULTS: We found that the 50% mouse lethal dose of the nicked dichain EL-HN fragment (EL-HN-DC) was 0.5 µg and its neurotoxicity was the highest among the L-HN's of the four serotypes of BoNT (A/B/E/F). The cleavage efficiency of EL-HN-DC toward synaptosome associated protein 25 (SNAP25) in vitro was 3-fold higher than that of the single chain at the cellular level, and showed 200-fold higher animal toxicity. The EL-HN-DC fragment might enter neuro-2a cells via binding to SV2C to efficiently cleave SNAP25. CONCLUSIONS: The EL-HN fragment showed good biological activities in vivo and in vitro, and could be used as a drug screening model and to further explore the molecular mechanism of its transmembrane transport.


Asunto(s)
Toxinas Botulínicas Tipo A , Ratones , Animales , Toxinas Botulínicas Tipo A/toxicidad , Toxinas Botulínicas Tipo A/química , Toxinas Botulínicas Tipo A/genética , Serogrupo , Biología
5.
Sensors (Basel) ; 23(20)2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37896573

RESUMEN

Predictive maintenance is a proactive approach to maintenance in which equipment and machinery are monitored and analyzed to predict when maintenance is needed. Instead of relying on fixed schedules or reacting to breakdowns, predictive maintenance uses data and analytics to determine the appropriate time to perform maintenance activities. In industrial applications, machine boxes can be used to collect and transmit the feature information of manufacturing machines. The collected data are essential to identify the status of working machines. This paper investigates the design and implementation of a machine box based on the ROS framework. Several types of communication interfaces are included that can be adopted to different sensor modules for data sensing. The collected data are used for the application on predictive maintenance. The key concepts of predictive maintenance include data collection, a feature analysis, and predictive models. A correlation analysis is crucial in a feature analysis, where the dominant features can be determined. In this work, linear regression, a neural network, and a decision tree are adopted for model learning. Experimental results illustrate the feasibility of the proposed smart machine box. Also, the remaining useful life can be effectively predicted according to the trained models.

6.
Inflamm Res ; 70(6): 705-717, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34014331

RESUMEN

BACKGROUND: Previous studies have demonstrated that Luteolin has a positive effect on epithelial barrier integrity by promoting the function of tight protein, however, little is known about the underline mechanism of Luteolin. In this study, we constructed Caco-2 cell monolayer to explore the effects and the regulation mechanism of Luteolin in intestinal epithelial barrier integrity. METHODS: Caco-2 cells were co-treated with TNF-α, Interferon-γ (IFN-γ) and Luteolin for 24 h. Overexpression or knockdown of SHP-1 was applied to study the effects of protein phosphoserine phosphatase-1 (SHP-1) on epithelial barrier integrity. Cell viability was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Barrier function was detected by trans-epithelial electrical resistance (TEER) and FITC-dextran assay. The expression levels of SHP-1, phosphorylation signal transducer and activator of transcription 3 (p-STAT3), STAT3 and tight junction proteins were measured by qRT-PCR or western blot. In vivo model of ulcerative colitis was established to detect the function of Luteolin in ulcerative colitis. RESULTS: We clarified that Luteolin protected intestinal epithelial barrier function of Caco-2 monolayers by increasing the resistance values and tight junction (TJ) protein expression. The expression of OCLN, CLDN1, and ZO1 was increased by Luteolin, while the expression of CLDN2 was decreased. Furthermore, Luteolin significantly alleviated the symptom of ulcerative colitis in DSS-induced mice. The in vitro cell model proved that overexpression of SHP-1 promotes the epithelial barrier function and knockdown of SHP-1 or STAT3 activation destroyed the protective effects of Luteolin on the expression of TJ proteins. CONCLUSION: We found that the treatment of Luteolin promoted epithelial barrier function and Luteolin might preserve intestinal epithelial barrier function through suppression of STAT3 signaling pathway by SHP-1.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Luteolina/uso terapéutico , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Factor de Transcripción STAT3/metabolismo , Animales , Células CACO-2 , Permeabilidad de la Membrana Celular/efectos de los fármacos , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Sulfato de Dextran , Humanos , Luteolina/farmacología , Masculino , Ratones Endogámicos C57BL , Proteína Tirosina Fosfatasa no Receptora Tipo 6/genética , Transducción de Señal/efectos de los fármacos , Proteínas de Uniones Estrechas/genética , Proteínas de Uniones Estrechas/metabolismo
7.
J Environ Manage ; 300: 113711, 2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34509812

RESUMEN

The pilot-scale partial nitrification-anaerobic ammonia oxidation (PN-Anammox) process for landfill leachate treatment has been running stably for 2 years. The degradation characteristics of nitrogen removal performance of PN-Anammox in this system were discussed during shutdown, and different recovery strategies were analyzed from the perspective of economy and easy implementation. The results showed that during the 166 d dormancy period, the decrease in Anammox bacteria activity occurred earlier than that of Anammox bacteria, and both tended to slow down after 128 d. The recovery strategy of simulated wastewater was the fastest, followed by the pretreated landfill leachate recovery strategy with inoculation of some corresponding functional sludges, while the worst strategy was the direct pretreated landfill leachate recovery strategy. The recovery start-up of the pilot-scale PN-Anammox process further showed that microbial activities were difficult to recover simultaneously during operation using raw wastewater directly due to the presence of high NH4+-N levels and the coupling process, which easily led to the accumulation of NH4+-N or NO2-N, thereby inhibiting microbial activity. The addition of some functional bacteria was more conducive to the rapid recovery of microbial activity. This study provides a new strategy for the rapid recovery of microbial activity for the engineering application of the PN-Anammox process.


Asunto(s)
Nitrificación , Contaminantes Químicos del Agua , Reactores Biológicos , Desnitrificación , Nitrógeno , Oxidación-Reducción , Aguas del Alcantarillado
8.
Ecotoxicol Environ Saf ; 180: 483-490, 2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31121555

RESUMEN

In this study, powdery aerobic activated sludge (PAAS) was first prepared, and the removal rate, sorption capacity and mechanism of sorption uranium on PAAS was investigated. Before and after sorption, the surface morphology and structure of PAAS were characterized systematically using the Fourier transform infrared spectrometer (FTIR), the X-ray photoelectron spectrometer (XPS), and the scanning electron microscope (SEM-EDX). In this work, the sorption mechanism and efficiency of uranium on the PAAS was study with static batch and ion exchange experiments, meanwhile, some influencing factors such as solution pH, contact temperature, adsorbent dose of PAAS and different initial uranium concentrations were studied. The batch sorption experiments illustrated that pH had a little effect in the process of sorption uranium on PAAS and it has a good removal capacity in a wide pH range (pH = 3-8). When the pH of solution was 7, the removal efficiency of about 93% for uranium when the initial concentration of uranium was 10 mg/L and the concentration of PAAS was 1  g/L. The XPS demonstrated that there are some active functional groups for instance carboxyl (-COOH), Hydroxyl (-OH), Amino (-NH2) and so on in the PAAS, and that all can combine with uranium. After sorption, there is an obviously U signal (marked in green) in the PAAS by charactering with the FE-SEM. In addition, kinetic parameters were fitted by the first-order kinetic (R2 = 0.9738) model and the second-order kinetic model (R2 = 0.9998), the pseudo-secondary kinetic model was better to illustrate the sorption process, so the chemical action was dominant, and existed physical sorption. The sorption isotherms date of PAAS was well-fitted to the Langmuir model (R2 = 0.9688). In the experiment of ion exchange, the concentration of Na+ in the solution hardly changed, the release of the other three ions was K+

Asunto(s)
Modelos Teóricos , Aguas del Alcantarillado/química , Uranio/análisis , Aguas Residuales/química , Contaminantes Radiactivos del Agua/análisis , Purificación del Agua/métodos , Adsorción , Aerobiosis , Concentración de Iones de Hidrógeno , Intercambio Iónico , Cinética , Polvos , Temperatura
9.
Huan Jing Ke Xue ; 44(4): 2032-2039, 2023 Apr 08.
Artículo en Zh | MEDLINE | ID: mdl-37040953

RESUMEN

The distribution characteristics, correlations, and potential ecological risks of 13 antibiotics and 10 antibiotic resistance genes (ARGs) in 16 water sources in Wuhan were analyzed using solid-phase extraction-ultra-high performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS) and real-time quantitative PCR technology. The distribution characteristics and correlations and potential ecological risks of antibiotics and resistance genes in this region were analyzed. The results showed that a total of nine antibiotics were detected in the 16 water source samples, and the concentration range was ND-177.36 ng·L-1. The concentration distribution presented as follows:Tributary Jushui River

Asunto(s)
Antibacterianos , Agua , Antibacterianos/análisis , Cromatografía Liquida , Espectrometría de Masas en Tándem , Organismos Acuáticos , Medición de Riesgo
10.
Sci Total Environ ; 878: 162982, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-36958564

RESUMEN

The effects of salinity on anaerobic nitrogen and sulfide removal were investigated in a coupled anammox and short-cut sulfur autotrophic denitrification (SSADN) system. The results revealed that salinity had significant nonlinear effects on the nitrogen and sulfur transformations in the coupled system. When the salinity was <2 %, the anammox and SSADN activities increased with increasing salinity, and the total nitrogen removal rate, S0 production rate, and nitrite production rate were 0.41 kg/(m3·d), 0.37 kg/(m3·d), and 0.28 kg/(m3·d), respectively. With continuous increase of salinity, the performances of the anammox and SSADN gradually decreased, and the three indicators decreased to 0.14 kg/(m3·d), 0.22 kg/(m3·d), and 0.14 kg/(m3·d) at 5 % salinity, respectively. When the salinity reached 5 %, the nitrogen removal contribution of anammox decreased to 68.4 %, while the contribution of the sulfur autotrophic denitrification increased to 31.6 %. The coupled system recovered in a short time after alleviation of the salinity stress, and the SSADN activity recovery was faster than anammox. The microbial community structure and functional microbial abundance in the coupled system changed significantly with increasing salinity, and the functional microbial abundance after recovery was considerably different from the initial state.


Asunto(s)
Desnitrificación , Aguas Residuales , Nitrógeno/análisis , Oxidación Anaeróbica del Amoníaco , Reactores Biológicos , Oxidación-Reducción , Azufre , Estrés Salino
11.
Bioresour Technol ; 354: 127194, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35452827

RESUMEN

In this study, two short-cut sulfur autotrophic denitrification (SSADN) reactors were initiated using different reduced sulfur forms as electron donors and their effects on the start-up speed of the SSADN process, NO2--N accumulation characteristics, and microbial community were investigated. Results revealed that during the same period, due to the relatively slow S0 dissolution rate, the NO2--N production rate realized by microorganisms in S0-SSADN (NO2--N production rate (NPR), 174 mg/(L·d)) was significantly slower than S2--SSADN (NPR, 679 mg/(L·d)). The NO2--N accumulation efficiency (NAE) was maintained > 80%, which was significantly higher than S2--SSADN. In the SSADN system using different reduced sulfur forms, the microbial community structure and abundance considerably differed. The main sulfur-oxidizing bacteria (SOB) in S0-SSADN were Sulfurimonas (6.5%) and Thiobacillus (5.3%). The main SOB species in S2--SSADN was Thiomonas (13.6%). Thermomonas played an important role in the two reactors as an important NO3--N denitrifying bacteria species.


Asunto(s)
Reactores Biológicos , Desnitrificación , Procesos Autotróficos , Bacterias , Electrones , Nitratos , Nitrógeno/química , Dióxido de Nitrógeno , Azufre/química
12.
J Phys Condens Matter ; 34(37)2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35779515

RESUMEN

As an inherent property of the device itself, nonlinearity in micro-/nano- electromechanical resonators is difficult to eliminate, and it has shown a wide range of applications in basic research, sensing and other fields. While many application scenarios require tunability of the nonlinearity, inherent nonlinearity of a mechanical resonator is difficult to be changed. Here, we report the experimental observation of a Joule heating induced tuning effect on the nonlinearity of graphene mechanical resonators. We fabricated multiple graphene mechanical resonators and detected their resonant properties by an optical interference method. The mechanical vibration of the resonators will enter from the linear to the nonlinear intervals if we enhance the external driving power to a certain value. We found that at a fixed drive power, the nonlinearity of a mechanical resonator can be tuned by applying a dc bias current on the resonator itself. The tuning mechanism could be explained by the nonlinear amplitude-frequency dependence theory. Our results may provide a research platform for the study of mechanical nonlinearity by using atomic-thin layer materials.

13.
Dis Markers ; 2022: 4524032, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35069932

RESUMEN

BACKGROUND: Chronological age (CA) is not a perfect proxy for the true biological aging status of the body. A new biological aging measure, phenotypic age (PhenoAge), has been shown to capture morbidity and mortality risk in the general US population and diverse subpopulations. This study was aimed at evaluating the association between PhenoAge and long-term outcome of patients with multivessel coronary artery disease (CAD). METHODS: A total of 609 multivessel CAD patients who received PCI attempt and with follow-up were enrolled. The clinical outcome was all-cause mortality on follow-up. PhenoAge was calculated using an equation constructed from CA and 9 clinical biomarkers. Cox proportional hazards regression models and receiver operating characteristic (ROC) curves were performed to evaluate the association between PhenoAge and mortality. RESULTS: Overall, patients with more diseases had older PhenoAge and phenotypic age acceleration (PhenoAgeAccel). After a median follow-up of 33.5 months, those with positive PhenoAgeAccel had a significantly higher incidence of all-cause mortality (P = 0.001). After adjusting for CA, Cox proportional hazards models showed that both PhenoAge and PhenoAgeAccel were significantly associated with all-cause mortality. Even after further adjusting for confounding factors, each 10-year increase in PhenoAge was also associated with a 51% increased mortality risk. ROC curves revealed that PhenoAge, with an area under the curve of 0.705, significantly outperformed CA, the individual clinical chemistry measure, and other risk factors. When reexamining the ROC curves using various combinations of variables, we found that PhenoAge provides additional predictive power to all models. CONCLUSIONS: In conclusion, PhenoAge was strongly associated with all-cause mortality even after adjusting for CA. Our findings suggest that PhenoAge measure may be complementary in predicting mortality risk for patients with multivessel CAD.


Asunto(s)
Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Envejecimiento , Enfermedad de la Arteria Coronaria/etiología , Humanos , Intervención Coronaria Percutánea/efectos adversos , Modelos de Riesgos Proporcionales , Factores de Riesgo , Resultado del Tratamiento
14.
Front Med (Lausanne) ; 8: 755705, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34869454

RESUMEN

Background: Little is known about whether sarcopenia predicts incident depressive symptoms in older adults. Using the nationally representative data from the China Health and Retirement Longitudinal Study (CHARLS), we conducted cross-sectional and longitudinal analyses to estimate the association between sarcopenia and depressive symptoms among older adults. Methods: The sample comprised 7,706 participants aged at least 60 years (50.6% women; mean age 68.0 ± 6.5) from the CHARLS 2015. Based on the Asian Working Group for Sarcopenia 2019 (AWGS 2019) criteria, sarcopenia status was classified into three types: no-sarcopenia, possible sarcopenia, and sarcopenia. Depressive symptoms were assessed using the validated 10-items of the Center for Epidemiologic Studies Depression Scale. A cross-sectional analysis was used to examine the relationship between sarcopenia status and depressive symptoms. A total of 4,652 participants without depressive symptoms were recruited from the same cohort in 2015 and were followed up in 2018. Cox proportional hazards regression models were conducted to examine the effect of sarcopenia status on subsequent depressive symptoms with the report of hazard ratio (HR). Results: The prevalence of depressive symptoms in total populations, no-sarcopenia, possible sarcopenia, and sarcopenia individuals were 27.1% (2085/7706), 21.5% (927/4310), 33.6% (882/2627), and 35.9% (276/769), respectively. Both possible sarcopenia (OR: 1.75, 95% CI: 1.46-2.10) and sarcopenia (OR: 1.64, 95% CI: 1.23-2.19) were positively associated with higher odds of depressive symptoms (all p < 0.01). During the 3.7 years of follow-up, 956 cases (20.6%) with incident depressive symptoms were identified. In the longitudinal analysis, individuals with the diagnosed possible sarcopenia (HR: 1.27, 95% CI: 1.01-1.58) and sarcopenia participants (HR: 1.49, 95% CI: 1.06-2.09) were more likely to have new onset depressive symptoms than no-sarcopenia peers. Conclusions: Both possible sarcopenia and sarcopenia, assessed using the AWGS 2019 criteria, were independent predictors for the occurrence of depressive symptoms among Chinese older adults. Our findings provided new evidence supporting the longitudinal connection between sarcopenia and mental health problems, it also provides further justification for timely identification and management of both possible sarcopenia and sarcopenia as part of comprehensive strategies to fight against depressive symptoms.

15.
Sci Rep ; 11(1): 7776, 2021 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-33833338

RESUMEN

This study investigated associations between cardiometabolic diseases, frailty, and healthcare utilization and expenditure among Chinese older adults. The participants were 5204 community-dwelling adults aged at least 60 years from the China Health and Retirement Longitudinal Study. Five cardiometabolic diseases were assessed including hypertension, dyslipidemia, diabetes, cardiac diseases and stroke. Frailty status was based on five criteria: slowness, weakness, exhaustion, inactivity, and shrinking. Participants were deemed frailty if they met at least three criteria. As the number of cardiometabolic diseases increased, so did the prevalence of frailty, and the proportion of healthcare utilization, including outpatient visit and inpatient visit. Moreover, the total healthcare expenditure and the odds of catastrophic health expenditure were increased with the number of cardiometabolic disorders. After adjusting for covariates, cardiometabolic diseases were positively associated with higher odds of frailty, incurring outpatient and inpatient visit. And individuals with 2 or more cardiometabolic diseases had a higher odds of catastrophic health expenditure than persons with non-cardiometabolic disease. Participants who were frailty were more likely to report higher odds of healthcare utilization. These findings suggest that both cardiometabolic diseases and frailty assessment may improve identification of older adults likely to require costly, extensive healthcare.


Asunto(s)
Fragilidad/epidemiología , Evaluación Geriátrica , Gastos en Salud/estadística & datos numéricos , Cardiopatías/epidemiología , Aceptación de la Atención de Salud/estadística & datos numéricos , Anciano , China/epidemiología , Femenino , Anciano Frágil , Humanos , Hipertensión/epidemiología , Vida Independiente , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Prevalencia , Encuestas y Cuestionarios
16.
Angiology ; 72(8): 740-748, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33657867

RESUMEN

Limited data are available on long-term outcomes and health status in the treatment of in-stent coronary chronic total occlusion (IS-CTO) and de novo coronary chronic total occlusion (de novo CTO). This study compared the long-term clinical outcomes and health status of percutaneous coronary intervention (PCI) for patients with IS-CTO versus patients with de novo CTO in the drug-eluting stent era. We screened 483 consecutive patients with 1 CTO lesion, including 81 patients with IS-CTO and 402 patients with de novo CTO. Propensity score matching was used to balance baseline characteristics between the 2 groups. The clinical end point was major adverse cardiac events (MACE). The success rates of CTO lesion revascularization were similar in both groups. In the propensity score-matched patients, after a median follow-up of 36 months, MACE was observed in 32.8% of patients with IS-CTO versus 13.5% of the patients with de novo CTO (P < .001), mainly driven by target-vessel revascularization (21.9% vs 6.7%; P < .01). Moreover, patients with IS-CTO had significantly worse Seattle Angina Questionnaire anginal stability scores than the patients with de novo CTO. In conclusion, patients with IS-CTO after PCI had a worse clinical outcome, mainly MACE, and a poorer anginal stability in the long term than patients with de novo CTO.


Asunto(s)
Oclusión Coronaria/terapia , Reestenosis Coronaria/terapia , Intervención Coronaria Percutánea/instrumentación , Stents , Anciano , Enfermedad Crónica , Angiografía Coronaria , Oclusión Coronaria/diagnóstico por imagen , Oclusión Coronaria/fisiopatología , Reestenosis Coronaria/diagnóstico por imagen , Reestenosis Coronaria/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/efectos adversos , Medición de Riesgo , Factores de Riesgo , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento
17.
Bioresour Technol ; 316: 123926, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32758922

RESUMEN

Stabilization of nitrification process and reduction of NO3--N concentration in effluent are the keys to realize mainstream application of partial nitrification-anaerobic ammonia oxidation (PN-anammox) process. The sulfur-based autotrophic denitrification (SADN) process was coupled with the PN-anammox in a single reactor to enhance and stabilize the nitrogen removal performance, and the feasibility and reaction characteristics of the coupling system under mainstream conditions were investigated. The results showed that the NO3- of PN-anammox effluent dropped from 22 to 24 mg/L to 5 mg/L after the SADN process coupled, and the total nitrogen removal efficiency and total nitrogen removal rate reached 83.5% and 0.15 kg/(m3·d), respectively. This coupling system doesn't need to over-strengthen PN control. Batch experiments showed that sulfur autotrophic oxidizing bacteria used O2 to oxidize S2- in the coupling system, which competed with SADN to remove NO3-. Moreover, Nitrosomonas, Candidatus Brocadia and Thiobacillus were the main genera for nitrogen and sulfur conversion.


Asunto(s)
Desnitrificación , Nitrógeno/análisis , Procesos Autotróficos , Reactores Biológicos , Nitrificación , Oxidación-Reducción , Azufre , Aguas Residuales
18.
Bioresour Technol ; 302: 122880, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32007855

RESUMEN

The denitrification (DN), partial nitrification (PN) and Anammox processes were coupled in an auto-recycling integration device to remove nitrogen from the supernatant of sludge reduction pretreatment. The nitrogen removal performance of the device and the effect of organic matter concentration on the nitrogen transformation were discussed. The results showed that DN, PN and Anammox are well coupled and total nitrogen (TN) removal rate reached 0.85 kg/(m3·d). The pre-DN process can achieve the removal of NO3--N produced by the back-end PN-Anammox process without the need of reflux pump drive. When the influent NH4+-N concentration was approximately 400 mg/L, the effluent TN concentration was less than 20 mg/L. The fluctuation of organic matter led to changes of nitrogen transformation in the system, and the best ratio of influent CODbio/TN was 0.7-0.9. Nitrosomonas and Candidatus Brocadia played important roles in the nitrogen removal process as the main functional microorganisms of PN and Anammox, respectively.


Asunto(s)
Desnitrificación , Nitrificación , Reactores Biológicos , Nitrógeno , Oxidación-Reducción , Aguas del Alcantarillado
19.
Bioresour Technol ; 297: 122430, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31761626

RESUMEN

The effects on nitrogen removal from landfill leachate were compared between the denitrification (DN) direct coupling in Partial nitrification (PN)-Anammox (DN+(PN-Anammox)) and pre-DN followed by PN-Anammox (DN-PN-Anammox). Both processes can achieve coupling and high nitrogen removal. However, the DN+(PN-Anammox) process was not conducive to the treatment of high-COD wastewater. The total nitrogen removal rate (TNRR) and total nitrogen removal efficiency (TNRE) were stable at 0.31 kg/(m3·d) and 76.3%. When UASB was added to denitrification and transform the process into DN-PN-Anammox, the influent NH4+-N and COD concentrations were increased to 2230 and 2612 mg/L, TNRR and TNRE reached 0.45 kg/(m3·d) and 96.7%, respectively. The DN-PN-Anammox process not only was able to make full use of degradable COD in wastewater to realize the NO3--N removal, but also benefited the growth of autotrophic bacteria. The DN-PN-Anammox reduced the oxygen supply and was more conducive to the treatment of highly-concentrated mature landfill leachate.


Asunto(s)
Desnitrificación , Contaminantes Químicos del Agua , Reactores Biológicos , Nitrificación , Nitrógeno , Oxidación-Reducción
20.
Nanomaterials (Basel) ; 9(11)2019 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-31766154

RESUMEN

The effects of divacancy, including isolated defects and extended line defects (ELD), on the thermal transport properties of graphene nanoribbons (GNRs) are investigated using the Nonequilibrium Green's function method. Different divacancy defects can effectively tune the thermal transport of GNRs and the thermal conductance is significantly reduced. The phonon scattering of a single divacancy is mostly at high frequencies while the phonon scattering at low frequencies is also strong for randomly distributed multiple divacancies. The collective effect of impurity scattering and boundary scattering is discussed, which makes the defect scattering vary with the boundary condition. The effect on thermal transport properties of a divacancy is also shown to be closely related to the cross section of the defect, the internal structure and the bonding strength inside the defect. Both low frequency and high frequency phonons are scattered by 48, d5d7 and t5t7 ELD. However, the 585 ELD has almost no influence on phonon scattering at low frequency region, resulting in the thermal conductance of GNRs with 585 ELD being 50% higher than that of randomly distributed 585 defects. All these results are valuable for the design and manufacture of graphene nanodevices.

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