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1.
Medicine (Baltimore) ; 103(16): e37739, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38640294

RESUMEN

Some patients with heatstroke also experience intracerebral hemorrhage (ICH). However, clinical case reports of heatstroke-induced ICH are rare. The risk factors for cerebral hemorrhage after heatstroke remain unknown. The present study evaluated the clinical characteristics and risk factors of patients with heatstroke-related ICH. In this retrospective observational study, we collected data on all ICHs after heatstroke occurred between 2012 and 2022. The characteristics of patients with heatstroke-induced ICH were described. The risk factors for cerebral hemorrhage after heatstroke were examined using logistic regression analysis. In total, 177 patients were included in this study, and 11 patients with ICH secondary to heatstroke were identified. Variables with P values of <.05 in univariate models, comparing the cerebral hemorrhage and control groups, included heatstroke cause, temperature, heart rate, respiratory rate, vasopressor use, mechanical ventilation use, Acute Physiology and Chronic Health Evaluation II, total bilirubin, creatinine, platelet count, prothrombin time, procalcitonin, creatine kinase, disseminated intravascular coagulation (DIC) occurrence, and DIC score. Multivariate logistic regression showed that heatstroke patients with higher DIC scores (odds ratio, 18.402, 95% confidence interval, 1.384-244.763, P = .027) and higher creatine kinase levels (odds ratio, 1.021, 95% confidence interval, 1.002-1.041, P = .033) were at a higher risk of developing ICH. The death rate was higher in the cerebral hemorrhage group than in the control group (P = .042). Heatstroke-related cerebral hemorrhage may be associated with elevated creatinine levels and DIC severity (International Society on Thrombosis and Hemostasis score) after heatstroke, and heatstroke with cerebral hemorrhage may accelerate death.


Asunto(s)
Hemorragia Cerebral , Golpe de Calor , Humanos , Creatinina , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/epidemiología , Factores de Riesgo , Estudios Retrospectivos , Golpe de Calor/complicaciones , Creatina Quinasa
2.
Chem Commun (Camb) ; 60(39): 5197-5200, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38651297

RESUMEN

Through the integration of CRISPR/Cpf1 with optogenetics and a reduction-responsive motif, we have developed a photoactivatable cross-linked crRNA that enables precise genome editing upon light exposure. This system also allows for termination of editing activity through external application of reducing agent. The dual-stimuli-responsive CRISPR/Cpf1 editing process operates in a unique OFF → ON → OFF sequence, making it a valuable tool for investigating time-sensitive biological events.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Edición Génica/métodos , Sistemas CRISPR-Cas/genética , Humanos , Luz , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Proteínas Asociadas a CRISPR/metabolismo , Proteínas Asociadas a CRISPR/química , ARN/química , ARN/genética
3.
Anal Bioanal Chem ; 416(7): 1647-1655, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38305859

RESUMEN

Target-based drug discovery technology based on cell membrane targets has gained significant traction and has been steadily advancing. However, current methods still face certain limitations that need to be addressed. One of the challenges is the laborious preparation process of screening materials, which can be time-consuming and resource-intensive. Additionally, there is a potential issue of non-specific adsorption caused by carrier materials, which can result in false-positive results and compromise the accuracy of the screening process. To address these challenges, this paper proposes a target-based cell membrane affinity ultrafiltration technology for active ingredient discovery in natural products. In this technique, the cell membranes of human lung adenocarcinoma epithelial cells (A549) with a high expression of epidermal growth factor receptor (EGFR) were incubated with candidate drugs and then transferred to an ultrafiltration tube. Through centrifugation, components that interacted with EGFR were retained in the ultrafiltration tube as "EGFR-ligand" complex, while the components that did not interact with EGFR were separated. After thorough washing and eluting, the components interacting with EGFR were dissociated and further identified using LC-MS, enabling the discovery of bioactive compounds. Moreover, the target-based cell membrane affinity ultrafiltration technology exhibited commendable binding capacity and selectivity. Ultimately, this technology successfully screened and identified two major components from the Curcumae Rhizoma-Sparganii Rhizoma (CS) herb pair extracts, which were further validated for their potential anti-tumor activity through pharmacological experiments. By eliminating the need for laborious preparation of screening materials and the potential non-specific adsorption caused by carriers, the development of target-based cell membrane affinity ultrafiltration technology provides a simplified approach and method for bioactive compounds discovery in natural sources.


Asunto(s)
Productos Biológicos , Ultrafiltración , Humanos , Ultrafiltración/métodos , Productos Biológicos/farmacología , Tecnología , Receptores ErbB , Membrana Celular
4.
Bioresour Technol ; 386: 129495, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37454959

RESUMEN

Anaerobic reactors often underperform compared to expectations. To identify the key factors, an ecological anaerobic reactor (EAR) with vertical partitions was developed and compared to a physical anaerobic reactor (PAR) as the control. It was observed that EAR achieved a much higher organic loading rate (OLR) compared to PAR (>100 vs 45 kg/m3·d). The different vertical distribution characteristics of anaerobic granular sludge could be ascribed to two vertical distribution patterns dominated in EAR and PAR, i.e., ecological and physical distributions. It was revealed that ecological distribution was formed by the habitat selection, resulting in promoted substrate availability and higher OLR. While physical distribution was mainly affected by hydraulic selection via granule settleability, causing declined substrate availability and lower OLR. Consequently, the promoted ecological distribution and weakened hydraulic selection in EAR contributed to its good performance. Overall, these findings could offer novel concepts for the development of reactors towards high performance.


Asunto(s)
Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Anaerobiosis , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos
5.
Bioresour Technol ; 386: 129514, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37473785

RESUMEN

Calcification is a critical challenge for achieving anaerobic reactors' high-efficiency. However, the aggregation caused by calcification at both granular sludge and reactor levels remain to be fully understood. Herein, this study investigated the characteristics of calcification in an anaerobic reactor (RH) operated with high calcium-containing wastewater for over 200-day. It was found that the COD removal efficiency in RH dropped from 98.00 ± 2.06% to 41.29 ± 3.79%, which was much lower than that of 95.50 ± 1.55% in the control reactor. Morphological analysis revealed that the high influent calcium caused granular sludge aggregation, which would further led to the rapid deterioration in bioavailability, as confirmed by both mass transfer tests and theoretical simulations. Moving forward, statistical analysis showed that the proportion of bioavailability deterioration zones in RH system (61.68%) was similar to the decreased COD removal efficiency (57.87%), proving that bioavailability deterioration was the culprit for the performance decline of anaerobic reactor.


Asunto(s)
Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Anaerobiosis , Disponibilidad Biológica , Calcio , Reactores Biológicos
6.
Front Immunol ; 14: 1159195, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37350963

RESUMEN

Introduction: Damage to endothelial glycocalyx (EGCX) can lead to coagulation disorders in sepsis. Heat stroke (HS) resembles sepsis in many aspects; however, it is unclear whether EGCX injury is involved in its pathophysiology. The purpose of this study was to examine the relationship between the damage of EGCX and the development of coagulation disorders during HS. Methods: We retrospectively collected 159 HS patients and analyzed coagulation characteristics and prognosis of HS patients with or without disseminated intravascular coagulation (DIC). We also replicated a rat HS model and measured coagulation indexes, pulmonary capillary EGCX injury in HS rats. Finally, we evaluated the effect of the antioxidant N-acetylcysteine (NAC) on HS-initiated EGCX injury and coagulation disorders. Results: Clinical data showed that HS patients complicated with DIC had a higher risk of death than HS patients without DIC. In a rat HS model, we found that rats subjected to heat stress developed hypercoagulability and platelet activation at the core body temperature of 43°C, just before the onset of HS. At 24 h of HS, the rats showed a consumptive hypo-coagulation state. The pulmonary capillary EGCX started to shed at 0 h of HS and became more severe at 24 h of HS. Importantly, pretreatment with NAC substantially alleviated EGCX damage and reversed the hypo-coagulation state in HS rats. Mechanically, HS initiated reactive oxidative species (ROS) generation, while ROS could directly cause EGCX damage. Critically, NAC protected against EGCX injury by attenuating ROS production in heat-stressed or hydrogen peroxide (H2O2)-stimulated endothelial cells. Discussion: Our results indicate that the poor prognosis of HS patients correlates with severe coagulation disorders, coagulation abnormalities in HS rats are associated with the damage of EGCX, and NAC improves HS-induced coagulopathy, probably through its protection against EGCX injury by preventing ROS generation.


Asunto(s)
Trastornos de la Coagulación Sanguínea , Golpe de Calor , Sepsis , Ratas , Animales , Acetilcisteína/farmacología , Células Endoteliales , Glicocálix , Especies Reactivas de Oxígeno , Peróxido de Hidrógeno , Estudios Retrospectivos , Trastornos de la Coagulación Sanguínea/tratamiento farmacológico , Trastornos de la Coagulación Sanguínea/etiología , Golpe de Calor/tratamiento farmacológico , Sepsis/complicaciones
7.
Sci Total Environ ; 887: 163787, 2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37149192

RESUMEN

Solid carbon source (SCS) has attracted increasing research interests considering its merits of sustainable organic matter release capacity, safe transportation, easy management, and no need for frequent addition. In this study, the organic matter release capacities of five selected natural (milled rice and brown rice) and synthetic (PLA, PHA, PCL) SCSs were systematically investigated. The results showed that brown rice was the preferable SCS with high COD release potential, release rate and maximum accumulation of 309.2 mg-COD/g-SCS, 581.3 mg-COD/L·d and 6183.3 mg-COD/L, respectively. The cost for COD supply of brown rice stood at $1.0/kg-COD with considerable economic viability. The organic matter release process of brown rice could be well depicted by Hixson-Crowell model with a rate constant of -1.10. The addition of activated sludge could enhance the organic matter release of brown rice, evidenced by the increased release of VFAs with a proportion up to 97.1 % in the total organic matter. Moreover, the mass flow of carbon showed that the addition of activated sludge could improve the carbon utilization rate, and the peak value could achieve 45.4 % in 12 days. The unique dual-enzyme system, consisting of exogenous hydrolase from microorganisms in activated sludge and the endogenous amylase from brown rice, was supposed to be the main reason for the superior carbon release capacity of brown rice over other SCSs. This study was expected to offer an economic and effective SCS for the biological treatment of low-carbon wastewater.


Asunto(s)
Oryza , Purificación del Agua , Aguas del Alcantarillado , Eliminación de Residuos Líquidos/métodos , Carbono , Reactores Biológicos
8.
J Mass Spectrom Adv Clin Lab ; 29: 2-8, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37234251

RESUMEN

Introduction: Tyrosine kinase inhibitors (TKIs) are widely used in tumor treatment. The detection of these medicines by liquid chromatography-tandem mass spectrometry (LC-MS/MS) can avoid the interference of structurally similar compounds. Objectives: This study aimed to develop and validate a new LC-MS/MS assay for the quantification of eight tyrosine kinase inhibitors in human plasma and to preliminarily evaluate the clinical utility of the therapeutic drug monitoring method. Methods: Plasma samples were prepared by simple protein precipitation and separated using an ultra-high-performance reversed phase column. Detection was achieved using a triple quadrupole mass spectrometer in the positive ionization mode. The assay was validated against standard guidelines. We reviewed and analyzed the results of 268 plasma samples obtained from patients administered imatinib and other TKIs collected from January 2020 to November 2021 at Zhongshan Hospital. The analytes were separated and quantified within 3.5 min. Results: The newly developed method demonstrated linearity for the detected drug concentration in the range of 20 to 2000 ng/ml for gefitinib (r2 = 0.991) and crizotinib (r2 = 0.992), 50 to 5000 ng/ml for nilotinib (r2 = 0.991) and imatinib (r2 = 0.995), 1500-150,000 ng/ml for vemurafenib (r2 = 0.998), 1000-100,000 ng/ml for pazopanib (r2 = 0.993), 0.5-100 ng/ml for axitinib (r2 = 0.992) and 5-500 ng/ml for sunitinib (r2 = 0.991) and N-desethyl sunitinib (r2 = 0.998). The lower limit of quantification (LLOQ) was 20 ng/ml for gefitinib and crizotinib, 50 ng/ml for nilotinib and imatinib, 1500 ng/ml for vemurafenib, 1000 ng/ml for pazopanib, 0.5, and 5 ng/ml for sunitinib and N-desethyl sunitinib, respectively. Specificity, precision, accuracy, and stability were tested, and met the requirements of the guidelines. At the same dose, there was no significant difference in plasma drug concentration between the original imatinib medicine and the generic medicine after patent expiration. Conclusion: We developed a sensitive and reliable method for the quantification of eight TKIs.

9.
Dalton Trans ; 52(7): 2175-2181, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36723095

RESUMEN

The structure of CsPbI3 nanocrystals (NCs) with excellent photoelectric properties easily collapses, which hinders their application in light-emitting diodes (LEDs). Herein, we accomplished the synthesis of efficient and stable CsPbI3 NCs by regulating structural rigidity under the synergistic effect of Mg2+ and AcO- ions. The introduced AcO- and Mg2+ ions increase surface steric hindrance and defect formation energy, which enhances the structural rigidity of the perovskite. As a result, the CsPbI3 NCs display an outstanding photoluminescence quantum yield of 95.7%, in conjunction with reduced defect state density, balanced carrier injection, and distinguished conductivity. Remarkably, the modified CsPbI3 NCs exhibit excellent stability under ambient conditions for 180 days and can even survive when the temperature reaches 150 °C. Given their enhanced structural rigidity, LEDs made from these modified CsPbI3 NCs exhibit a maximum luminance and an EQE of 3281 cd m-2 and 13.2%, respectively, which are significantly improved compared with those of unmodified CsPbI3 NC LEDs.

10.
Environ Sci Technol ; 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36629799

RESUMEN

Elemental sulfur (S0) is widely utilized in environmental pollution control, while its low bioavailability has become a bottleneck for S0-based biotechnologies. Biogenic sulfur (bio-S0) has been demonstrated to have superior bioavailability, while little is known about its mechanisms thus far. This study investigated the bioavailability and relevant properties of bio-S0 based on the denitrifying activity of Thiobacillus denitrificans with chemical sulfur (chem-S0) as the control. It was found that the conversion rate and removal efficiency of nitrate in the bio-S0 system were 2.23 and 2.04 times those of the chem-S0 system. Bio-S0 was not pure orthorhombic sulfur [S: 96.88 ± 0.25% (w/w)]. Trace organic substances detected on the bio-S0 surface were revealed to contribute to its hydrophilicity, resulting in better dispersibility in the aqueous liquid. In addition, the adhesion force of T. denitrificans on bio-S0 was 1.54 times that of chem-S0, endowing a higher bacterial adhesion efficiency on the sulfur particle. The weaker intermolecular binding force due to the low crystallinity of bio-S0 led to enhanced cellular uptake by attached bacteria. The mechanisms for the superior bioavailability of bio-S0 were further proposed. This study provides a comprehensive view of the superior bioavailability of bio-S0 and is beneficial to developing high-quality sulfur resources.

11.
Angew Chem Int Ed Engl ; 62(5): e202212413, 2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36453982

RESUMEN

The CRISPR/Cas system is one of the most powerful tools for gene editing. However, approaches for precise control of genome editing and regulatory events are still desirable. Here, we report the spatiotemporal and efficient control of CRISPR/Cas9- and Cas12a-mediated editing with conformationally restricted guide RNAs (gRNAs). This approach relied on only two or three pre-installed photo-labile substituents followed by an intramolecular cyclization, representing a robust synthetic method in comparison to the heavily modified linear gRNAs that often require extensive screening and time-consuming optimization. This tactic could direct the precise cleavage of the genes encoding green fluorescent protein (GFP) and the vascular endothelial growth factor A (VEGFA) protein within a predefined cutting region without notable editing leakage in live cells. We also achieved light-mediated myostatin (MSTN) gene editing in embryos, wherein a new bow-knot-type gRNA was constructed with excellent OFF/ON switch efficiency. Overall, our work provides a significant new strategy in CRISPR/Cas editing with modified circular gRNAs to precisely manipulate where and when genes are edited.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Edición Génica/métodos , Sistemas CRISPR-Cas/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , ARN Guía de Sistemas CRISPR-Cas
12.
Water Sci Technol ; 86(7): 1668-1680, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36240303

RESUMEN

Veterinary antibiotics in swine wastewater has drawn great public attention. The removal processes of sulfamethizole (SMZ), enrofloxacin (ENR) and chlortetracycline (CTC) were investigated in the high-rate anaerobic process. The continuous experiments demonstrated that in 3 L working volume and with the organic loading rate 5 kg/(m3·d) rised to 20 kg/(m3·d), the average removal efficiencies of the high-rate anaerobic bioreactor for SMZ, ENR and CTC were 0, 54 and 100%, respectively. By using fixed-bed adsorption models, the saturation time of SMZ, ENR and CTC were 4 hydraulic retention time (HRT) (24 h), 8 HRT (48 h) and 372 HRT (2,232 h). In the batch experiments, the adsorption and biodegradation characteristics of anaerobic granular sludge were determined. In the high-rate anaerobic bioreactor, SMZ removal process mainly relied on the adsorption but it was very weak; ENR removal process was based on the adsorption and biodegradation; CTC removal process was based to a large extent on the adsorption because of the big capacity of AnGS. These results were helpful to create a rational basis for designing more suitable treatment systems as feasible barriers to the release of antibiotics into the environment.


Asunto(s)
Clortetraciclina , Aguas del Alcantarillado , Anaerobiosis , Animales , Antibacterianos , Reactores Biológicos , Enrofloxacina , Sulfametizol , Porcinos , Eliminación de Residuos Líquidos/métodos , Aguas Residuales
13.
J Therm Biol ; 109: 103326, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36195392

RESUMEN

Injury to the intestinal epithelial cells and loss of the intestinal barrier are critical to heatstroke. To reveal the mechanism through which heatstroke leads to intestinal epithelial injury, the relationship between reactive oxygen species (ROS), c-Jun NH2-terminal kinase (JNK), and lysosomes were studied in intestinal epithelial cells subjected to heat stress. Cells of heat stress groups were incubated at 43 °C for 1 h, then incubated at 37 °C as indicated. Control group cells were incubated at 37 °C. Cell-counting kit-8 assay was used to assess cell viability. Cells were labeled with 2'-7'dichlorofluorescin diacetate and acridine orange (AO) staining, respectively, the total ROS and AO were detected by confocal laser scanning microscopy and flow cytometry. Apoptosis was analyzed by flow cytometry using annexin V-fluorescein isothiocyanate/prodium iodide staining, the expressions of mitogen-activated protein kinases were detected by western blotting. Heat stress induced apoptosis and inhibited cell viability, the production of ROS, and lysosomal injury in IEC-6 cells. After pretreatment with the lysosomal cathepsin inhibitor E64, the JNK inhibitor SP600125, or the ROS scavenger NAC, the effect of heat stress on apoptosis or lysosomal injury was significantly attenuated. In conclusion, heat stress induced apoptosis, lysosomal injury, and the accumulation of ROS in IEC-6 cells; mechanistically, this occurred through the ROS-induced activation of JNK signaling, which mediated the lysosomal injury and ultimately apoptosis.


Asunto(s)
Trastornos de Estrés por Calor , Golpe de Calor , Enfermedades Intestinales , Naranja de Acridina/metabolismo , Naranja de Acridina/farmacología , Animales , Anexina A5/metabolismo , Anexina A5/farmacología , Apoptosis , Catepsinas/metabolismo , Catepsinas/farmacología , Células Epiteliales/metabolismo , Fluoresceínas/metabolismo , Fluoresceínas/farmacología , Trastornos de Estrés por Calor/metabolismo , Respuesta al Choque Térmico , Yoduros/metabolismo , Yoduros/farmacología , Isotiocianatos/metabolismo , Isotiocianatos/farmacología , Lisosomas/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/farmacología , Fenazopiridina/metabolismo , Fenazopiridina/farmacología , Ratas , Especies Reactivas de Oxígeno/metabolismo
14.
Small Methods ; 6(4): e2200163, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35266646

RESUMEN

In recent years, CsPbX3 (X = Cl, Br, I) perovskite quantum dots (QDs) have been considered as the most promising materials for light-emitting diodes (LEDs). However, the advances of CsPbX3 quantum dot-based light emitting diodes (QLEDs) still lagged behind inorganic III-V LEDs and other organic LEDs. Herein, a strategy to improve the performances of perovskite QLEDs is reported by utilizing the localized surface plasmon resonance (LSPR) effects of Au nanospheres (NSs). It is accomplished by introducing a Au NS layer into the electron transport layer of Ca2+ -CsPbBr3 QLEDs, where the diameter and spacing of Au NSs and the interaction distance between the Ca2+ -CsPbBr3 QD and Au NS layers are modulated, according to the theoretical simulation of Finite-difference time-domain. As a result, the photoluminescence quantum yield of Ca2+ -CsPbBr3 QD layer is improved from 31.5% to 73.3%. Finally, the luminance of Ca2+ -CsPbBr3 QLEDs is improved from 16824 to 63931 cd m-2 and external quantum efficiency (EQE) is improved from 4.2% to 10.5%. The radiative transition rate can be remarkably modulated from 0.7 × 107 to 6.6 × 107 s-1 . The enhancement in luminance and EQE are the best values in the LSPR modified perovskite QLEDs and the strategy offered in this work fits with other LEDs and optoelectrical devices.

15.
J Phys Chem Lett ; 13(10): 2379-2387, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35254835

RESUMEN

Zero-dimensional (0D) crystal structure perovskite NCs have reemerged as promising materials owing to their superior long-term stability; however, their poor conductivity leads to the inferior electrical performances and critically restricts the optoelectronic application of 0D perovskite materials. Herien, the alloyed 0D crystal structure Cs2ZnxPb1-xCl4 nanorods (NRs) have been synthesized by the modified hot-injection method, which emits bright blue-violet light at 408 nm, and the optimized photoluminescence quantum yield (PLQY) reaches 26%. The Cs2Zn0.88Pb0.12Cl4 NRs display more excellent air stability and an order of magnitude higher conductivity than CsPbCl3 nanocube films. In addition, we dope Mn2+ ions into the Cs2Zn0.88Pb0.12Cl4 NRs, which accomplished the optimized PLQY of 40.3% and polarized emission with r = 0.19. The light-emitting diodes (LEDs) based on Mn2+ ion doped Cs2Zn0.88Pb0.12Cl4 NRs exhibit a chromaticity coordinate (CIE) of (0.36, 0.33), an EQE of 0.3%, and a maximum luminance of 98 cd m-2. This work has enriched ideas for the production of white light perovskite LEDs.

16.
Environ Res ; 210: 112763, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35114142

RESUMEN

Anammox granular sludge processes are an attractive and efficient biotechnology in the field of wastewater treatment. In this study, the stratification patterns of anammox granular sludge bed (GSB) at steady states were illustrated and its relationship to microbial activity and community were systematically investigated under different nitrogen loading rates (NLRs). Morphological observation and quantitive particle size distribution analysis demonstrated that the GSB at low NLR was mainly composed of micro and fine granules with a big difference between bottom and top sludge layers. But at high NLR, the volumetric mean diameter (VMD) of GSB increased with the size distribution width (Span) declined forming a more homogeneous and coarse granules population. The particle size distribution parameters of GSB could be fast characterized by the optical lightness (L*) parameter (r = -0.771, p < 0.01, n = 16) and held a significant correlation with the nitrogen removal rate (NRR) of anammox system (r > 0.9, p < 0.05). The microbial spatial distribution patterns of different sludge layers were further investigated by high-throughput sequencing. The microbial community α-diversity index and microbial abundance matrix proved that the community structure tend to coverage at high NLR. Significant difference of the relative abundance of microbial community was detected under different NLRs. The VMD of GSB held a significant correlation with the relative abundance of AnAOB (r = 0.556, p < 0.01, n = 16) and other common accompanying bacteria (Denitratisoma and Chloroflexi). This study proved that the apparent particle size distribution patterns of GSB could be a potential auxiliary indicator to reflect the microbial activity and community, which can facilitate the innovative process monitor of anammox system based on visual features.


Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado , Oxidación Anaeróbica del Amoníaco , Anaerobiosis , Reactores Biológicos/microbiología , Nitrógeno , Oxidación-Reducción , Tamaño de la Partícula , Aguas del Alcantarillado/química
17.
Small ; 18(9): e2106147, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34985192

RESUMEN

The α-CsPbI3 nanocrystals (NCs) easily transform into yellow non-perovskite, accompanying with declining photoelectric properties that restricting their practical applications in diverse fields. Herein, the highly luminescent and robust α-CsPbI3 NCs is achieved through engineering the lattice symmetry of perovskite, enabled by the synergistic effect of NO3- ion passivation and Ca2+ ion doping. The introduced NO3- ions enhance the phase-change energy barrier and the surface steric hindrance, thus promoting the formation of α-CsPbI3 NCs with hyper-symmetric crystal structure, while the Ca2+ ion doping contributes to improving their lattice symmetry by significant regulation of the tolerance factor. As a result, the obtained α-CsPbI3 NCs display an outstanding photoluminescence quantum yield of 96.6%, together with the reduced defect state density and eminent conductivity. Most importantly, the as-engineered α-CsPbI3 NCs exhibit excellent stability under ambient conditions for 9 months and UV illumination for 32 h. It displays brilliant thermal stability, maintaining luminous intensity for 15 min under 140 °C, and performing desired durability and reversibility, evidenced by 160 °C cyclic test and 120 °C reversibility test. Given enhanced robustness, the as-engineered α-CsPbI3 NCs based light-emitting-diode devices are constructed, exhibiting a power efficiency of 105.3 lm W-1 and the excellent working stability for 18 h.


Asunto(s)
Calcio , Nitratos , Compuestos de Calcio , Óxidos , Titanio
18.
Sci Total Environ ; 807(Pt 3): 151024, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-34662610

RESUMEN

Anaerobic granular sludge (AnGS) is the core of anaerobic granular sludge bed system. In this study, the effect and its mechanism of stopping substrate supply on function of AnGS were investigated. The cutoff of exogenous substrate supply triggered AnGS to enter the dormant state. Some methanization microorganisms sporulated. The number and activity of methanization microorganisms based on 16S rDNA and 16S rRNA/16S rDNA ratio declined and stayed at 45.5% and 0.06% (bacteria), 48.7% and 0.39% (archaea) of the initial vegetative value, respectively. The resuming of exogenous substrate supply promoted AnGS to restore the vegetative state. The spores disappeared. The specific methanization activity of AnGS returned to the original level of 35.82 mL-CH4/g-VSS·d, but the delay time for gas production (DTGS) was prolonged from 9.54 to 18.04 h (0-132 d). The dormancy of methanization microorganisms was the main cause for the fluctuation of apparent function and the stability of intrinsic function of AnGS under starvation stress. The dormancy stabilized the structure and sustained the methanization community of AnGS via the reduction of EPS (structure binder/energy reserve) consumption.


Asunto(s)
Aguas del Alcantarillado , Anaerobiosis , ADN Ribosómico , ARN Ribosómico 16S/genética
19.
Sci Total Environ ; 798: 149242, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34375252

RESUMEN

Cryopreservation is one of the effective methods for the preservation of anammox granular sludge (AnGS). However, the effects of cooling pretreatment on AnGS are still unclear. In this study, the effects of temperature decrease on AnGS property were investigated by designing different cooling modes: constant at room temperature 20-25 °C (CK), sharp cooling to 4 °C (S4), -20 °C (S20) and stepwise cooling to 4 °C (A4), -20 °C (A20). The results showed that compared with CK, the cooling modes in S4, S20, A4 and A20 improved the physical preservability of AnGS, slowing down the changes of color, shape and structure; and elevated the preservation rate of functional bacteria Planctomycetes (phylum level) and Candidatus Brocadia (genus level). The preservation rate of live cells in different experimental groups was 48.4 ± 1.8%(CK), 61.1 ± 3.3%(S4), 37.8 ± 0.8%(S20), 81.7 ± 4.8%(A4), 61.9 ± 3.1%(A20), respectively. The Anaerobic Ammonium Oxidation Bacteria (AnAOB) in the stepwise cooling mode (A4 and A20) were found to enter the dormant state and form "dormant zoogloea", while the AnAOB in the sharp cooling mode (S4 and S20) were observed to enter the shock state with a little change. The findings in this work (especially the dormant state of AnAOB) are helpful to understand the effect of temperature decrease on AnGS and to promote the development of AnGS preservation technology.


Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado , Anaerobiosis , Nitrógeno , Oxidación-Reducción , Temperatura
20.
Sci Total Environ ; 795: 148681, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34328917

RESUMEN

Anammox granule is the key support of anammox sludge bed reactor. In this study, the anammox granules from a steady-state reactor were divided into 6 groups to investigate their dimension effects. The results of batch cultivation showed that the anammox granules with VMD (volume surface mean diameter) of 2.17 mm had the maximum SAA (specific anammox activity) of 399.6 ± 37.6 mg-N/(g-VSS·d). The bacterial community analysis demonstrated that Candidatus Kuenenia was the main detectable AnAOB genus in the anammox granules. Q-PCR together with flow cytometry indicated that the total number of viable AnAOB cells ascended with the increasing anammox granular size, suggesting the enhancement of nitrogen removal potential. On the contrary, the mass transfer efficiency descended with the increasing granular size, indicating the restriction of nitrogen removal performance. The maximum SAA was ascribed to the optimal match between nitrogen removal potential and mass transfer efficiency. The results of this study are helpful to comprehend the nitrogen removal capacity of anammox granules and to promote the optimization of anammox process.


Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado , Anaerobiosis , Nitrógeno , Oxidación-Reducción
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