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Excess light causes severe photodamage to photosystem II (PSII) where the primary charge separation for electron transfer takes place. Dissection of mechanisms underlying the PSII maintenance and repair cycle in green algae promotes the usage of genetic engineering and synthetic biology to improve photosynthesis and biomass production. In this study, we systematically analyzed the high light (HL) responsive immunophilin genes in Chlamydomonas (Chlamydomonas reinhardtii) and identified one chloroplast lumen-localized immunophilin, CYN28, as an essential player in HL tolerance. Lack of CYN28 caused HL hypersensitivity, severely reduced accumulation of PSII supercomplexes and compromised PSII repair in cyn28. The thylakoid FtsH (filamentation temperature-sensitive H) is an essential AAA family metalloprotease involved in the degradation of photodamaged D1 during the PSII repair cycle and was identified as one potential target of CYN28. In the cyn28 mutant, the thylakoid FtsH undergoes inefficient turnover under HL conditions. The CYN28-FtsH1/2 interaction relies on the FtsH N-terminal proline residues and is strengthened particularly under HL. Further analyses demonstrated CYN28 displays peptidyl-prolyl isomerase (PPIase) activity, which is necessary for its physiological function. Taken together, we propose that immunophilin CYN28 participates in PSII maintenance and regulates the homeostasis of FtsH under HL stress via its PPIase activity.
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Chlamydomonas , Tilacoides , Tilacoides/metabolismo , Complejo de Proteína del Fotosistema II/metabolismo , Péptido Hidrolasas/metabolismo , Inmunofilinas/análisis , Inmunofilinas/metabolismo , Chlamydomonas/metabolismo , Isomerasa de Peptidilprolil/metabolismo , LuzRESUMEN
Few studies expressed the ß-galactosidase encoding gene from L. plantarum in E. coli so far. In the present study, the recombinant ß-galactosidase from L. plantarum FMNP01 was used as a catalyst in transgalactosylation to form tri-GOS and lactosucrose. In the presence of lactose and sucrose, six transfer products were formed in the transgalactosylation reaction with recombinant ß-galactosidase L.pFMNP01Gal as a catalyst. Three transfer products were tri-galacto-oligosaccharides (tri-GOS), lactosucrose, and lactulose; the other three transfer products needed to be identified further. Based on a single factor test and response surface methodological approach, the optimal transgalactosylation conditions of the production of tri-GOS and lactosucrose were determined as initial sugar concentration of 50%, lactose: sucrose ratio of 1:2, enzyme concentration of 3 U/mL, and reaction time of 6 h at 50 °C resulting in a maximum tri-GOS concentration of 47.69 ± 1.36 g/L and a maximum lactosucrose concentration of 8.18 ± 0.97 g/L.
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Lactosa , Sacarosa , Escherichia coli/genética , Oligosacáridos , beta-Galactosidasa/genéticaRESUMEN
Studies have found that anxiety is among the common negative emotions in individuals with substance use disorders. Anxiety affects drug abstention motivation, but the mechanism underlying this effect is still unclear. The current study aimed to examine the relationship among anxiety, regulatory emotional self-efficacy, psychological resilience and drug abstention motivation in an attempt to explore the mechanism underlying drug abstention motivation. The participants were 732 men with substance use disorders who were sent to compulsory rehabilitation in China. All participants completed measures of anxiety, regulatory emotional self-efficacy, psychological resilience and drug abstention motivation through questionnaires. The results indicated that anxiety negatively predicts drug abstention motivation. Regulatory emotional self-efficacy mediates the relationship between anxiety and drug abstention motivation. In addition, psychological resilience moderates the mediation between anxiety and regulatory emotional self-efficacy. The current results are not only helpful for understanding the relationship between anxiety and drug abstention motivation from the perspective of emotion but also of great significance for guiding individuals with substance use disorders in enhancing their drug abstention motivation by reducing negative emotion.
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Motivación , Trastornos Relacionados con Sustancias , Masculino , Humanos , Estudios Transversales , Ansiedad/psicología , Trastornos Relacionados con Sustancias/psicología , ChinaRESUMEN
OBJECTIVE: The aim of the study was to investigate the effect of zinc-bearing palygorskite (Zn-Pal) on rumen fermentation by in vitro gas-production system. METHODS: In trial, 90 incubators were evenly divided into five groups: control (0% Zn-Pal), treatment I (0.2% Zn-Pal), treatment II (0.4% Zn-Pal), treatment III (0.6% Zn-Pal), and treatment IV (0.8% Zn-Pal). The contents of zinc for treatments were 0, 49, 98, 147, 196 mg/kg, respectively. The main chemical composition and microstructure of Zn-Pal was investigated by X-ray diffraction. The physicochemical features were evaluated by Zeta potential analysis, cation-exchange capacity, ethylene blue absorption and specific surface area (the Brunauer-Emmett-Teller method). In vitro gas production (GP) was recorded at 3, 6, 9, 12, 18, 24, 36, 48, 60, and 72 h incubation. Incubation was stopped at 0, 6, 12, 24, 48, and 72 h and the inoculants were tested for pH, microbial protein yield (MCP), NH3-N, volatile fatty acids (VFAs), lipopolysaccharide (LPS). RESULTS: The results showed that the GP in the treatment groups was not significantly different from the control groups (p>0.05). Compared to the control group, pH was higher at 24 h, 48 h (p<0.05), and 72 h (p<0.01) (range 6 to 7). The concentration of NH3-N in the three treatment groups was higher than in the control group at 24 h (p<0.01), meanwhile, it was lower at 48 h and 72 h (p<0.01), except in the treatment IV. The concentration of MCP in treatment I group was higher than in the control at 48 h (p<0.01). Compared with control, the LPS concentration in treatment III became lower at 12 h (p<0.05). Total VFAs in treatments were higher than in the control at 24 h, 48 h (p<0.05). CONCLUSION: These results suggest that the addition of Zn-Pal can improve the rumen fermentation, especially when adding 0.2% Zn-Pal.
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Protein engineering has been a research hotspot to improve the catalytic efficiency of industrially important enzymes. In the present study, a novel computational strategy was developed to in silico screen mutants with enhanced binding interaction between enzyme and substrate as well as catalytic efficiency. Through homology modeling and molecular dynamics (MD) simulation, four key residues related to substrate binding were identified in the endo-polygalacturonase BiPG28A from Bispora sp. MEY-1. Further analyses of the conformation, hydrogen bond interactions, and binding free energy revealed that lysine at position 129 (subsite - 2) has the strongest affinity to substrate. Biochemical and calorimetry experiments confirmed the functional role of Lys129 in substrate binding through non-covalent interactions. The common role of Lys129 was also verified in another GH28 endo-polygalacturonase. Distinguished from other protein engineering strategies involving structure resolution and construction of certain enzymes, this computational strategy represents an insightful and efficient approach to develop a "designed" enzyme with significantly enhanced binding affinity and catalytic efficiency.
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Poligalacturonasa/química , Poligalacturonasa/metabolismo , Ingeniería de Proteínas , Ascomicetos/enzimología , Ascomicetos/genética , Catálisis , Dominio Catalítico , Enlace de Hidrógeno , Modelos Moleculares , Simulación de Dinámica Molecular , Mutagénesis Sitio-Dirigida , Conformación Proteica , Especificidad por SustratoRESUMEN
The effect of different sodium salt concentration on anaerobic digestion of kitchen waste was investigated. The methane production performance, the corresponding methane production model and sodium salt inhibition model were studied, and the degradation efficiency was analyzed. With the increase of sodium salt concentration, the methane yield and the maximal methane production rate decreased along with the increase of lag phase time. The highest methane yield of 594 mL/g-VSadded (VS: volatile solids) was found with no sodium salt addition while the lowest was obtained with addition of 16 g/L NaCl. The declines of the methane yield were negligible when the sodium salt concentration was below 8 g/L, which corresponded to <10% inhibiting efficiency. In contrast, a sharp decrease of methane yield was observed with addition of >8 g/L NaCl (causing 17-80% inhibition). Five kinds of regression models were developed to describe the sodium salt inhibition efficiency, and the cubic regression model of y = 0.508 + 2.401x - 0.369x(2) + 0.033x(3) showed the best fitting. The volatile fatty acids/ethanol gradually accumulated along with the increase of the sodium salt concentration, and the volatile solid removal efficiency represented a gradual decline accordingly. It is recommended that the sodium salt concentration in the anaerobic digesters should be controlled below 8 g/L in order to avoid intense methane inhibition.
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Reactores Biológicos , Eliminación de Residuos/métodos , Sodio/metabolismo , Anaerobiosis , Ácidos Grasos Volátiles/metabolismo , Metano/metabolismoRESUMEN
Grandparental involvement in childrearing has been associated with children's social-emotional development, yet findings are mixed. Grandparental involvement is a multidimensional concept that includes both quantity (i.e., the degree of grandparental involvement) and quality aspects (i.e., the quality of parent-grandparent coparenting and the quality of grandparenting practices). This study included both quantity and quality aspects to identify heterogeneous patterns of grandparental involvement and examined the associations between distinct patterns of grandparental involvement and children's social-emotional outcomes. Participants were 428 families with Chinese preschoolers (Mage = 53.75 months, SD = 10.32; 51.4% boys). Primary parental and grandparental caregivers completed the questionnaires. Four patterns of grandparental involvement emerged: the low-involvement mediocre-quality, the median, the high-involvement uneven-quality, and the high-involvement high-quality groups. Heterogeneous patterns of grandparental involvement exist and are differentially associated with children's social-emotional development. Children with grandparents in the high-involvement high-quality group demonstrated higher levels of social skills than those in the low-involvement mediocre-quality group and the high-involvement uneven-quality group. They also showed the lowest level of problem behaviors. This study highlights variations in grandparental involvement and helps to clarify previous inconsistent findings regarding the role of grandparental involvement in child development. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Desarrollo Infantil , Crianza del Niño , Abuelos , Humanos , Masculino , Femenino , Abuelos/psicología , Preescolar , Desarrollo Infantil/fisiología , Crianza del Niño/psicología , Crianza del Niño/etnología , Responsabilidad Parental/psicología , China , Relaciones Intergeneracionales , Emociones/fisiología , Adulto , Pueblos del Este de AsiaRESUMEN
Electrochemical pretreatment (EPT) has shown to be superior in improving acidogenic co-fermentation (Co-AF) of waste activated sludge (WAS) and food waste (FW) for volatile fatty acids (VFAs). However, the influence of EPT electrode materials on the production of electrogenerated oxidants (such as singlet oxygen (1O2) and reactive chlorine species (RCS)), as well as their effects on properties of electrodes, the microbial community structure and functional enzymes remain unclear. Therefore, this study investigated the effects of various metal oxide coated electrodes (i.e., Ti/PbO2, Ti/Ta2O5-IrO2, Ti/SnO2-RuO2, and Ti/IrO2-RuO2) on EPT and subsequent Co-AF of WAS-FW. The results showed that EPT with Ti/PbO2, Ti/Ta2O5-IrO2, Ti/SnO2-RuO2 and Ti/IrO2-RuO2 electrodes generated 165.3-848.2 mg Cl2/L of RCS and 5.643 × 1011-3.311 × 1012 spins/mm3 of 1O2, which significantly enhanced the solubilization and biodegradability of WAS-FW by 106.4 %-233.6 % and 177.3 %-481.8 %, respectively. Especially with Ti/Ta2O5-IrO2 as the electrode material, an appropriate residual RCS (2.0-10.4 mg Cl2/L) remained in Co-AF step, resulted in hydrolytic and acidogenic bacteria (e.g., Prevotella_7, accounting for 78.9 %) gradually become dominant rather than methanogens (e.g., Methanolinea and Methanothrix) due to their different tolerance to residual RCS. Meanwhile, the functional gene abundances of hydrolytic and acidogenic enzymes increased, while the methanogenic enzymes deceased. Consequently, this reactor produced the highest VFAs up to 545.5 ± 36.0 mg COD/g VS, which was 101.8 % higher than that of the Control (without EPT). Finally, the economic analysis and confirmatory experiments further proved the benefits of WAS-FW Co-AF with EPT.
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Electrodos , Ácidos Grasos Volátiles , Aguas del Alcantarillado , Ácidos Grasos Volátiles/metabolismo , Aguas del Alcantarillado/química , Cloro , Fermentación , Óxidos/química , Metales , Eliminación de Residuos Líquidos/métodos , Alimento Perdido y DesperdiciadoRESUMEN
The Chinese government has invested much money to help poor college students complete their studies, but the gratitude of the recipients remains to be further studied. This study proposed a parallel mediation model and used questionnaires to investigate 260 thousand college students of China to examine the impact of the level of social support on poor college students' gratitude and the mediating role played by social responsibility and relative deprivation. The results showed that social support positively predicted the gratitude level of poor college students; social responsibility and relative deprivation mediated the relationship between social support and gratitude; gender, school type and difficulty level had a significant influence on gratitude level. In short, education to improve the sense of gratitude of poor college students can be summarized as "two increases and one decrease": increase social support, enhance social responsibility, and reduce relative deprivation.
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The recirculation of chlorine within the kiln presents a major hurdle in co-processing domestic waste in cement kilns. This chlorine enrichment not only adversely affects the quality of cement, but also pose a serious challenge to the subsequent eco-friendly disposal of kiln dust. To solve this problem, a proper bypass system has been implemented in this study on a 4000 t/d new dry process cement rotary kiln, and the collection of chlorine-rich bypass dust outside the kiln (30 t/d) has been achieved. In addition, a comprehensive and innovative system has been developed, including water washing and subsequent triple-effect salt extraction, to achieve leaching of K+ and Cl from the bypass dust in the water rinsing liquid, while effectively removing harmful metal ions such as Pb2+. Finally, the extraction of high-purity KCl salt (6 tons/day, purity of 90 %) has been successfully achieved. It is worth noting that high-temperature flue gas rich in CO2 has been used to precipitate certain heavy metal ions, while steam from the waste-heat power generation system has been employed as a heat source for the potassium salt evaporation process. More importantly, all the materials, except for the KCl salt product, are returned to the cement kiln system without causing any secondary pollution. This study not only effectively addresses the negative impacts of chlorine element circulation within cement kilns during domestic waste co-processing, but also achieves a highly innovative engineering practice of transforming waste into valuable resources from kiln dust to high-purity KCl products. In brief, this work provides a reference example for future approaches to clean production, carbon reduction and resource utilization in the cement industry.
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Anaerobic digestion (AD) can be used as a stand-alone process or integrated as part of a larger biorefining process to produce biofuels, biochemicals and fertiliser, and has the potential to play a central role in the emerging circular bioeconomy (CBE). Agricultural residues, such as animal slurry, straw, and grass silage, represent an important resource and have a huge potential to boost biogas and methane yields. Under the CBE concept, there is a need to assess the long-term impact and investigate the potential accumulation of specific unwanted substances. Thus, a comprehensive literature review to summarise the benefits and environmental impacts of using agricultural residues for AD is needed. This review analyses the benefits and potential adverse effects related to developing biogas-centred CBE. The identified potential risks/challenges for developing biogas CBE include GHG emission, nutrient management, pollutants, etc. In general, the environmental risks are highly dependent on the input feedstocks and resulting digestate. Integrated treatment processes should be developed as these could both minimise risks and improve the economic perspective.
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Agricultura , Biocombustibles , Animales , Anaerobiosis , Ambiente , Poaceae , MetanoRESUMEN
In the anaerobic digestion (AD) process, the effects of humic acid (HA) derived from different feedstocks on AD are influenced by the variations in their structural composition and oxygen-containing functional groups. Thus, clarifying the structural differences of HA obtained from different feedstocks is crucial for understanding their impact on AD. In this study, the structure of five humic acids (HAs) derived from liquid digestate, food waste, silage corn straw, lignite and commercial HA, and their effects on AD were investigated. The study found that HA from food waste had more carboxyl groups, while straw-derived HA had more phenolic hydroxyl groups. Both types of HA had higher aromaticity and humification degree and showed significant inhibition effect on AD. HA from food waste had an average methanogenic inhibition rate of 43.5 % with 1 g/L HA added. In addition, commercial HA and HA derived from lignite had similar functional group types and aromaticity, with an average methanogenic inhibition rate of about 20 %. The study revealed that HAs with more carboxyl groups exhibited greater effectiveness in inhibiting AD, thereby confirming the influence of HA structures derived from different feedstocks on AD. In conclusion, this study provides valuable insights into the mechanism of HA effect on AD and offers guidance for future research focused on enhancing AD efficiency.
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Sustancias Húmicas , Eliminación de Residuos , Sustancias Húmicas/análisis , Anaerobiosis , Alimentos , Carbón Mineral , Digestión , Metano , Biocombustibles , Reactores BiológicosRESUMEN
The anaerobic digestion (AD) of food waste (FW) was easy to acidify and accumulate ammonia nitrogen. Adding exogenous materials to the AD system can enhance its conversion efficiency by alleviating acidification and ammonia nitrogen inhibition. This work investigated the effects of the addition frequency and additive amount on the AD of FW with increasing organic loading rate (OLR). When the OLR was 3.0 g VS per L per day and the concentration of the additives was 0.5 g per L per day, the stable methane yield reached 263 ± 22 mL per g VS, which was higher than that of the group without the additives (189 mL per g VS). Methanosaetaceae was the dominant archaea, with a maximum abundance of 93.25%. Through machine learning analysis, it was found that the optimal daily methane yield could be achieved. When the OLR was within the range of 0-3.0 g VS per L per day, the pH was within the range of 7.6-8.0, and the additive concentration was more than 0.5 g per L per day. This study proposed a novel additive and determined its usage strategy for regulating the AD of FW through experimental and simulation approaches.
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The ideal conditions for anaerobic digestion experiments with biochar addition are challenging to thoroughly study due to different experimental purposes. Therefore, three tree-based machine learning models were developed to depict the intricate connection between biochar properties and anaerobic digestion. For the methane yield and maximum methane production rate, the gradient boosting decision tree produced R2 values of 0.84 and 0.69, respectively. According to feature analysis, digestion time and particle size had a substantial impact on the methane yield and production rate, respectively. When particle sizes were in the range of 0.3-0.5 mm and the specific surface area was approximately 290 m2/g, corresponding to a range of O content (>31%) and biochar addition (>20 g/L), the maximum promotion of methane yield and maximum methane production rate were attained. Therefore, this study presents new insights into the effects of biochar on anaerobic digestion through tree-based machine learning.
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Reactores Biológicos , Carbón Orgánico , Anaerobiosis , Metano , Aprendizaje AutomáticoRESUMEN
Macrophages are central to the pathogenesis of kidney disease and serve as an effective therapeutic target for kidney injury and fibrosis. Among them, M2-type macrophages have double-edged effects regarding anti-inflammatory effects and tissue repair. Depending on the polarization of the M2 subtypes (M2a or M2c) in the diseased microenvironment, they can either mediate normal tissue repair or drive tissue fibrosis. In renal fibrosis, M2a promotes disease progression through macrophage-to-myofibroblast transition (MMT) cells, while M2c possesses potent anti-inflammatory functions and promotes tissue repair, and is inhibited. The mechanisms underlying this differentiation are complex and are currently not well understood. Therefore, in this study, we first confirmed that M2a-derived MMT cells are responsible for the development of renal fibrosis and demonstrated that the intensity of TGF-ß signaling is a major factor determining the differential polarization of M2a and M2c. Under excessive TGF-ß stimulation, M2a undergoes a process known as MMT cells, whereas moderate TGF-ß stimulation favors the polarization of M2c phenotype macrophages. Based on these findings, we employed targeted nanotechnology to codeliver endoplasmic reticulum stress (ERS) inhibitor (Ceapin 7, Cea or C) and conventional glucocorticoids (Dexamethasone, Dex or D), precisely modulating the ATF6/TGF-ß/Smad3 signaling axis within macrophages. This approach calibrated the level of TGF-ß stimulation on macrophages, promoting their polarization toward the M2c phenotype and suppressing excessive MMT polarization. The study indicates that the combination of ERS inhibitor and a first-line anti-inflammatory drug holds promise as an effective therapeutic approach for renal fibrosis resolution.
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Enfermedades Renales , Humanos , Enfermedades Renales/patología , Macrófagos , Factor de Crecimiento Transformador beta/farmacología , Fibrosis , Antiinflamatorios/farmacologíaRESUMEN
Syngas from pyrolysis/gasification process is a mixture of CO, CO2 and H2, which could be converted to CH4, so called syngas biomethanation. Its development is obstructed due to the low productivity and CO inhibition. The aim of this study was to demonstrate the feasibility of using syngas as the only carbon source containing high CO concentration (40%) for biomethanation. Lab-scale thermophilic bioreactor inoculated with anaerobic sludge was operated continuously for over 900 h and the shift of microbial structure were investigated. Results showed that thermophilic condition was suitable for syngas biomethanation and the microbes could adapt to high CO concentration. Higher processing capacity of 12.6 m3/m3/d was found and volumetric methane yield of 2.97 m3/m3/d was observed. These findings could strengthen the theoretical basis of syngas biomethanation and support its industrialization in the future.
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Reactores Biológicos , Aguas del Alcantarillado , MetanoRESUMEN
The parameters from full-scale biogas plants are highly nonlinear and imbalanced, resulting in low prediction accuracy when using traditional machine learning algorithms. In this study, a hybrid extreme learning machine (ELM) model was proposed to improve prediction accuracy by solving imbalanced data. The results showed that the best ELM model had a good prediction for validation data (R2 = 0.972), and the model was developed into the software (prediction error of 2.15 %). Furthermore, two parameters within a certain range (feed volume (FV) = 23-45 m3 and total volatile fatty acids of anaerobic digestion (TVFAAD) = 1750-3000 mg/L) were identified as the most important characteristics that positively affected biogas production. This study combines machine learning with data-balancing techniques and optimization algorithms to achieve accurate predictions of plant biogas production at various loads.
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Biocombustibles , Aprendizaje Automático , Algoritmos , Programas InformáticosRESUMEN
The amount of lignocellulose biomass and sludge is enormous, so it is of great significance to find a treatment combining the two substances. Co-hydrothermal carbonization (Co-HTC) has emerged as an efficient approach to dispose sludge. However, the improvement of sludge upgrading and combustion performance remains an important challenge during the Co-HTC of sludge. In this work, the Co-HTC of sludge and Fenton's reagent at different mixing ratios was proposed to achieve sludge reduction. Moreover, the addition of two kinds of biomass improved the adsorption capacity and combustion performance of hydrochars. When sludge and sawdust were the Co-HTC at the mass ratio of 1:3, the liquid phase Pb concentration decreased notably to 18.06%. Furthermore, the adsorption capacity of hydrochars was further improved by modification, which was in accordance with pseudo-second-order kinetics. Particularly, the hydrochars derived from the Co-HTC had higher heating value (HHV) and could be used as a clean fuel. This study proposed a new technical route of combining the HTC with Fenton's reagent and lignocellulose biomass, which could be served as a cleaner and eco-friendly treatment of sludge.
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Carbono , Aguas del Alcantarillado , Adsorción , Biomasa , Peróxido de Hidrógeno , Hierro , TemperaturaRESUMEN
This study evaluated the effects of bio-based carbon materials on methane production by anaerobic digestion. The results showed that biochar and hydrochar can promote cumulative methane yield by 15% to 29%. However, there was no statistical significance (p > 0.05) between hydrochar and biochar produced at different temperature on methane production. 16S rRNA gene sequencing and bioinformatics analysis showed that biochar and hydrochar enriched microorganism that might participate in direct interspecies electron transfer (DIET) such as Pseudomonadaceae, Bacillaceae, and Clostridiaceae. The the surface properties of the modified biochar were characterized with BET, Raman, FTIR and XPS. Bio-based carbon materials with uniform dispersion provided a stable environment for the DIET of microorganisms and electrons are transferred through aromatic functional groups on the surface of materials. This study reveals bio-based carbon materials surface properties on methane production in anaerobic digestion and provides a new approach to recycling spent coffee grounds.
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Reactores Biológicos , Grafito , Anaerobiosis , Carbono , Carbón Orgánico , Etanol , Metano , ARN Ribosómico 16S/genéticaRESUMEN
Slow coronary flow (SCF) phenomenon is a coronary microvascular disorder characterized by the delayed passage of contrast in the absence of obstructive epicardial coronary disease, and is an important clinical entity because it may be the cause of precordial pain when the body is at rest and/or during exercise. Although clinical and pathological features of SCF have been previously described, its etiopathogenesis remains unclear. The present study aims to investigate the risk factors of slow coronary flow, in order to provide the foundation for further exploration of potential mechanisms of SCF. A total of 47 consecutive patients with documented slow coronary flow, and 33 patients with normal coronary flow--as defined by TIMI frame count (TFC)--were recruited for this study. Clinical information was collected, and biochemical indicators including high-sensitivity C-reactive protein (hs-CRP), and a marker of systemic inflammation were detected. Logistic regression analysis was performed for statistical analysis. SCF patients had a higher level of serum uric acid (323.2 ± 79.3 vs. 282.8 ± 82.4 µmol/l, p = 0.03), 2-h postprandial blood glucose (8.6 ± 2.7 vs. 7.5 ± 1.8 mmol/l, p = 0.04), platelet count (165.9 ± 51.6 × 10(3) vs. 127.0 ± 32.0 × 10(3) cells/µl, p = 0.0003) and hs-CRP (3.4 ± 0.8 vs. 2.0 ± 0.9 mg/l, p < 0.0001) than those of patients in the control group. No marked differences in other variables were observed between the two groups. Logistic regression showed serum uric acid level (χ(2) = 3.84, ß = 0.007, p = 0.049), 2-h postprandial blood glucose (χ(2) = 5.02, ß = 0.277, p = 0.025) and blood platelet count (χ(2) = 12.16, ß = 0.026, p = 0.001) were independent predictors of SCF. When hs-CRP was included in the multivariate model, hs-CRP (χ(2) = 21.19, ß = 1.90, p < 0.0001) was the only independent predictor of SCF. These findings suggested that an elevation of serum uric acid level, 2-h postprandial blood glucose, and blood platelet count might be the causes of SCF, and inflammation was likely to be implicated in the causal pathway leading to SCF.