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1.
Regen Biomater ; 11: rbae024, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38628546

RESUMO

Diabetic wounds are a difficult medical challenge. Excessive secretion of matrix metalloproteinase-9 (MMP-9) in diabetic wounds further degrades the extracellular matrix and growth factors and causes severe vascular damage, which seriously hinders diabetic wound healing. To solve these issues, a double-network porous hydrogel composed of poly (methyl methacrylate-co-acrylamide) (p(MMA-co-AM)) and polyvinyl alcohol (PVA) was constructed by the high internal phase emulsion (HIPE) technique for the delivery of potassium sucrose octasulfate (PSO), a drug that can inhibit MMPs, increase angiogenesis and improve microcirculation. The hydrogel possessed a typical polyHIPE hierarchical microstructure with interconnected porous morphologies, high porosity, high specific surface area, excellent mechanical properties and suitable swelling properties. Meanwhile, the p(MMA-co-AM)/PVA@PSO hydrogel showed high drug-loading performance and effective PSO release. In addition, both in vitro and in vivo studies showed that the p(MMA-co-AM)/PVA@PSO hydrogel had good biocompatibility and significantly accelerated diabetic wound healing by inhibiting excessive MMP-9 in diabetic wounds, increasing growth factor secretion, improving vascularization, increasing collagen deposition and promoting re-epithelialization. Therefore, this study provided a reliable therapeutic strategy for diabetic wound healing, some theoretical basis and new insights for the rational design and preparation of wound hydrogel dressings with high porosity, high drug-loading performance and excellent mechanical properties.

2.
Nat Commun ; 15(1): 2888, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605015

RESUMO

Superconductivity is caused by electron pairs that are canonically isotropic, whereas some exotic superconductors are known to exhibit non-trivial anisotropy stemming from unconventional pairings. However, superconductors with hexagonal symmetry, the highest rotational symmetry allowed in crystals, exceptionally have strong constraint that is called emergent rotational symmetry (ERS): anisotropic properties should be very weak especially near the critical temperature Tc even for unconventional pairings such as d-wave states. Here, we investigate superconducting anisotropy of the recently-found hexagonal Kagome superconductor CsV3Sb5, which is known to exhibit various intriguing phenomena originating from its undistorted Kagome lattice formed by vanadium atoms. Based on calorimetry performed under accurate two-axis field-direction control, we discover a combination of six- and two-fold anisotropies in the in-plane upper critical field. Both anisotropies, robust up to very close to Tc, are beyond predictions of standard theories. We infer that this clear ERS violation with nematicity is best explained by multi-component nematic superconducting order parameter in CsV3Sb5 intertwined with symmetry breakings caused by the underlying charge-density-wave order.

3.
Cell Death Differ ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38570607

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a deadly malignancy with notable metabolic reprogramming, yet the pivotal metabolic feature driving ESCC progression remains elusive. Here, we show that methionine cycle exhibits robust activation in ESCC and is reversely associated with patient survival. ESCC cells readily harness exogenous methionine to generate S-adenosyl-methionine (SAM), thus promoting cell proliferation. Mechanistically, methionine augments METTL3-mediated RNA m6A methylation through SAM and revises gene expression. Integrative omics analysis highlights the potent influence of methionine/SAM on NR4A2 expression in a tumor-specific manner, mediated by the IGF2BP2-dependent stabilization of methylated NR4A2 mRNA. We demonstrate that NR4A2 facilitates ESCC growth and negatively impacts patient survival. We further identify celecoxib as an effective inhibitor of NR4A2, offering promise as a new anti-ESCC agent. In summary, our findings underscore the active methionine cycle as a critical metabolic characteristic in ESCC, and pinpoint NR4A2 as a novel methionine-responsive oncogene, thereby presenting a compelling target potentially superior to methionine restriction.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38630566

RESUMO

Identifying links within biological networks is important in various biomedical applications. Recent studies have revealed that each node in a network may play a unique role in different links, but most link prediction methods overlook distinctive node roles, hindering the acquisition of effective link representations. Subgraph-based methods have been introduced as solutions but often ignore shared information among subgraphs. To address these limitations, we propose a Subgraph-aware Graph Kernel Neural Network (SubKNet) for link prediction in biological networks. Specifically, SubKNet extracts a subgraph for each node pair and feeds it into a graph kernel neural network, which decomposes each subgraph into a combination of trainable graph filters with diversity regularization for subgraph-aware representation learning. Additionally, node embeddings of the network are extracted as auxiliary information, aiding in distinguishing node pairs that share the same subgraph. Extensive experiments on five biological networks demonstrate that SubKNet outperforms baselines, including methods especially designed for biological networks and methods adapted to various networks. Further investigations confirm that employing graph filters to subgraphs helps to distinguish node roles in different subgraphs, and the inclusion of diversity regularization further enhances its capacity from diverse perspectives, generating effective link representations that contribute to more accurate link prediction.

5.
J Hazard Mater ; 471: 134318, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38643582

RESUMO

Reactive chlorine species (RCS) are inevitably generated in electrochemical oxidation process for treating high-salinity industrial wastewater, thereby resulting in the competition with coexisting hydroxyl radicals (•OH) for oxidizing recalcitrant organic compounds. Due to the low redox potentials compared to •OH, the role of RCS has been often overlooked. In this work, we developed an electroactive membrane filtration (EMF) system that had a high removal efficiency (99.1 ± 0.5 %) for tetrabromobisphenol S (TBBPS) at low energy consumption (1.45 kWh m-3). Electron spin resonance spectroscopy and molecular probing tests indicated the predominance of Cl2•-, of which steady-state concentration (2.2 ×10-10 M) was extremely higher than those of ClO• (6.7 ×10-13 M), •OH (0.95 ×10-13 M), and Cl• (2.39 ×10-15 M). The density functional theory (DFT) and intermediate product analysis highlighted that Cl2•- radicals had a higher electrophilic attack efficacy than •OH radicals for inducing changes in the electron density of the carbon atoms around phenolic hydroxyl groups, thus leading to the generation of transition state intermediates and accelerating the degradation of TBBPS. Our work demonstrates the vital role of Cl2•- radicals for pollutant degradation, highlighting the potential of this technology for cost-effective removal of recalcitrant organic compounds from water and wastewater.

6.
Phys Rev Lett ; 132(10): 106601, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38518320

RESUMO

It has been theoretically predicted that perturbation of the Berry curvature by electromagnetic fields gives rise to intrinsic nonlinear anomalous Hall effects that are independent of scattering. Two types of nonlinear anomalous Hall effects are expected. The electric nonlinear Hall effect has recently begun to receive attention, while very few studies are concerned with the magneto-nonlinear Hall effect. Here, we combine experiment and first-principles calculations to show that the kagome ferromagnet Fe_{3}Sn_{2} displays such a magneto-nonlinear Hall effect. By systematic field angular and temperature-dependent transport measurements, we unambiguously identify a large anomalous Hall current that is linear in both applied in-plane electric and magnetic fields, utilizing a unique in-plane configuration. We clarify its dominant orbital origin and connect it to the magneto-nonlinear Hall effect. The effect is governed by the intrinsic quantum geometric properties of Bloch electrons. Our results demonstrate the significance of the quantum geometry of electron wave functions from the orbital degree of freedom and open up a new direction in Hall transport effects.

7.
Acta Cardiol ; 79(2): 215-223, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38456718

RESUMO

BACKGROUND: This study aimed to uncover the diagnostic value of circRNA (Circ)_0051386 in acute ST-segment elevation myocardial infarction (STEMI) and its predictive value for the occurrence of adverse major adverse cardiovascular events (MACEs). METHODS: This study included 166 patients with STEMI and 83 health donors. The expression levels of serum Circ_0051386 in these participants were quantified using real-time quantitative polymerase chain reaction (RT-qPCR). Additionally, the incidence of MACEs during a 6-month follow-up period after percutaneous coronary intervention (PCI) was collected in the STEMI patient cohort. RESULTS: Before and after propensity score matching (PSM), Circ_0051386 all had higher expression levels in the patients with STEMI than the normal subjects (all p < .001)and robust diagnosis values for the STEMI (AUC = 0.766, 0.779). Kaplan-Meier curves showed the high expression Circ_0051386 group had a higher occurrence rate of MACEs during a 6-month follow-up after PCI in patients with STEMI and this phenomenon was confirmed by internal validation (all p < .05). In addition, the multivariate COX regression showed gensini score (HR = 1.020, 95% CI = 1.002 - 1.038, p = .028) and Circ_0051386 (HR = 2.468, 95% CI =1.548-3.935, p < .001)were independent risk factors of the occurrence of MACEs in patients with STEMI after PCI. Pearson analysis presented that Circ_0051386 was positively correlated with gensini scores (r = 0.33), IL-1ß (r = 0.55)and TNF-α(r = 0.41). CONCLUSION: Our study indicated that Circ_0051386 is a biomarker of the diagnostic for STEMI and the predictor of the MACEs in STEMI patients after PCI. Its potential role in STEMI may be the regulation of inflammation in the vascular endothelial.


Assuntos
Infarto Miocárdico de Parede Anterior , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/genética , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Intervenção Coronária Percutânea/efeitos adversos , RNA Circular/genética , Arritmias Cardíacas/etiologia
8.
Plant Cell Rep ; 43(4): 106, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532109

RESUMO

KEY MESSAGE: Exogenous SL positively regulates pepper DS by altering the root morphology, photosynthetic character, antioxidant enzyme activity, stomatal behavior, and SL-related gene expression. Drought stress (DS) has always been a problem for the growth and development of crops, causing significant negative impacts on crop productivity. Strigolactone (SL) is a newly discovered class of plant hormones that are involved in plants' growth and development and environmental stresses. However, the role of SL in response to DS in pepper remains unknown. DS considerably hindered photosynthetic pigments content, damaged root architecture system, and altered antioxidant machinery. In contrast, SL application significantly restored pigment concentration modified root architecture system, and increased relative chlorophyll content (SPAD). Additionally, SL treatment reduced oxidative damage by reducing hydrogen peroxide (H2O2) (24-57%) and malondialdehyde (MDA) (79-89%) accumulation in pepper seedlings. SL-pretreated pepper seedlings showed significant improvement in antioxidant enzyme activity, proline accumulation, and soluble sugar content. Furthermore, SL-related genes (CcSMAX2, CcSMXL6, and CcSMXL3) were down-regulated under DS. These findings suggest that the foliar application of SL can alleviate the adverse effects of drought tolerance by up-regulating chlorophyll content and activating antioxidant defense mechanisms.


Assuntos
Antioxidantes , Capsicum , Compostos Heterocíclicos com 3 Anéis , Lactonas , Antioxidantes/metabolismo , Capsicum/metabolismo , Resistência à Seca , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Clorofila/metabolismo , Plântula/metabolismo , Secas
9.
Environ Sci Technol ; 58(13): 5878-5888, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498471

RESUMO

Data-driven machine learning (ML) provides a promising approach to understanding and predicting the rejection of trace organic contaminants (TrOCs) by polyamide (PA). However, various confounding variables, coupled with data scarcity, restrict the direct application of data-driven ML. In this study, we developed a data-knowledge codriven ML model via domain-knowledge embedding and explored its application in comprehending TrOC rejection by PA membranes. Domain-knowledge embedding enhanced both the predictive performance and the interpretability of the ML model. The contribution of key mechanisms, including size exclusion, charge effect, hydrophobic interaction, etc., that dominate the rejections of the three TrOC categories (neutral hydrophilic, neutral hydrophobic, and charged TrOCs) was quantified. Log D and molecular charge emerge as key factors contributing to the discernible variations in the rejection among the three TrOC categories. Furthermore, we quantitatively compared the TrOC rejection mechanisms between nanofiltration (NF) and reverse osmosis (RO) PA membranes. The charge effect and hydrophobic interactions possessed higher weights for NF to reject TrOCs, while the size exclusion in RO played a more important role. This study demonstrated the effectiveness of the data-knowledge codriven ML method in understanding TrOC rejection by PA membranes, providing a methodology to formulate a strategy for targeted TrOC removal.


Assuntos
Nylons , Purificação da Água , Osmose , Purificação da Água/métodos , Membranas Artificiais , Filtração
10.
Carbohydr Polym ; 334: 122028, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553227

RESUMO

The direct ink writing technique used in 3D printing technology is generally applied to designing biomedical hydrogels. Herein, we proposed a strategy for preparing all-chitin-based inks for wound dressing via direct ink writing technique. The ß-chitin nanofibers (MACNF) with a high aspect ratio were applied as a nanofiller to modulate the rheological properties of the alkaline dissolved chitin solution. The printing fidelity significantly depends on the MACNF introduction amount to the composite ink. 5-10 wt% MACNF ratio showed superior printing performance. The printed scaffold showed a uniform micron-sized pore structure and a woven network of nanofibers. Due to the good biocompatibility of chitin and the stereoscopic spatial skeleton, this scaffold showed excellent performance as a wound dressing, which can promote cell proliferation, collagen deposition and the angiogenesis of wounds, demonstrating its potential in biomedical applications. This approach successfully balanced the chitinous printability and biofunctions.


Assuntos
Quitina , Hidrogéis , Quitina/química , Hidrogéis/farmacologia , Hidrogéis/química , Bandagens , Colágeno , Impressão Tridimensional
11.
Front Plant Sci ; 15: 1346591, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476680

RESUMO

Gardeniae Fructus (Zhizi) serves as both a medicinal and edible substance and finds widespread use in various industries. There are often two kinds of medicinal materials in the market: Zhizi and Shuizhizi. Typically, Zhizi with small, round fruit is used for medicinal purposes, while Shuizhizi, characterized by large, elongated fruit, is employed for dyeing. Market surveys have revealed a diverse range of Zhizi types, and modern research indicates that Shuizhizi contains rich chemical components and pharmacological activities. In this study, we collected 25 batches of Zhizi and Shuizhizi samples, categorizing them based on appearance into obovate and round fruits, with seven length grades (A-G). Using the ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC-QQQ-MS/MS) method, we simultaneously quantified 13 main chemical components in fruits of Gardenia species. In addition, we compared the weight percentage of the pericarp, flesh, and seeds parts of samples with different traits, and quantified 13 chemical components in different parts. Results indicated that, aside from a few instances of overlapping fruit size ranges, Shuizhizi generally exhibits larger and longer dimensions than Zhizi. The weight proportion of the Shuizhizi pericarp is often higher than that of the Zhizi pericarp. Quantitative results highlighted significant differences in the chemical component content between Zhizi and Shuizhizi, with Shuizhizi generally containing higher levels of iridoids. The PCA and OPLS-DA analysis distinctly divided Shuizhizi and Zhizi, among which three iridoids, two organic acids, and one flavonoid made significant contributions to their classification. Cluster heatmap analysis also demonstrated complete separation between Zhizi and Shuizhizi, with clear distinctions among Zhizi samples from different origins. The distribution of the 13 chemical components in different Zhizi and Shuizhizi parts remained consistent, with iridoids and pigments concentrated in the seeds and flesh, and two organic acids and one flavonoid enriched in the pericarp. In summary, this study contributes valuable insights for classifying Zhizi and offers guidance on the rational use of Shuizhizi and the different parts of Zhizi.

12.
Nanomaterials (Basel) ; 14(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38470743

RESUMO

The niobium oxide dihalides have recently been identified as a new class of van der Waals materials exhibiting exceptionally large second-order nonlinear optical responses and robust in-plane ferroelectricity. In contrast to second-order nonlinear processes, third-order optical nonlinearities can arise irrespective of whether a crystal lattice is centrosymmetric. Here, we report third harmonic generation (THG) in two-dimensional (2D) transition metal oxide iodides, namely NbOI2 and TaOI2. We observe a comparable THG intensity from both materials. By benchmarking against THG from monolayer WS2, we deduce that the third-order susceptibility is approximately on the same order. THG resonances are revealed at different excitation wavelengths, likely due to enhancement by excitonic states and band edge resonances. The THG intensity increases for material thicknesses up to 30 nm, owing to weak interlayer coupling. After this threshold, it shows saturation or a decrease, due to optical interference effects. Our results establish niobium and tantalum oxide iodides as promising 2D materials for third-order nonlinear optics, with intrinsic in-plane ferroelectricity and thickness-tunable nonlinear efficiency.

13.
Aging Dis ; 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38502589

RESUMO

Osteoporotic fractures are the most severe complications of osteoporosis, characterized by poor bone quality, difficult realignment and fixation, slow fracture healing, and a high risk of recurrence. Clinically managing these fractures is relatively challenging, and in the context of rapid aging, they pose significant social hazards. The rapid advancement of disciplines such as biophysics and biochemistry brings new opportunities for future medical diagnosis and treatment. However, there has been limited attention to precision diagnosis and treatment strategies for osteoporotic fractures both domestically and internationally. In response to this, the Chinese Medical Association Orthopaedic Branch Youth Osteoporosis Group, Chinese Geriatrics Society Geriatric Orthopaedics Committee, Chinese Medical Doctor Association Orthopaedic Physicians Branch Youth Committee Osteoporosis Group, and Shanghai Association of Integrated Traditional Chinese and Western Medicine Osteoporosis Professional Committee have collaborated to develop this consensus. It aims to elucidate emerging technologies that may play a pivotal role in both diagnosis and treatment, advocating for clinicians to embrace interdisciplinary approaches and incorporate these new technologies into their practice. Ultimately, the goal is to improve the prognosis and quality of life for elderly patients with osteoporotic fractures.

14.
Food Res Int ; 182: 114077, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519167

RESUMO

Fruits flavor deterioration is extremely likely to occur during post-harvest storage, which not only damages quality but also seriously affects its market value. This work focuses on the study of fruits deterioration odorants during storage by describing their chemical compositions (i.e., alcohols, aldehydes, acids, and sulfur-containing compounds). Besides, the specific flavor deterioration mechanisms (i.e., fermentation metabolism, lipid oxidation, and amino acid degradation) inducing by factors (temperature, oxygen, microorganisms, ethylene) are summarized. Moreover, quality control strategies to mitigate fruits flavor deterioration by physical (temperature control, hypobaric treatment, UV-C, CA) and chemical (1-MCP, MT, NO, MeJA) techniques are also proposed. This review will provide useful references for fruits flavor control technologies development.


Assuntos
Frutas , Odorantes , Frutas/química , Aldeídos/análise , Álcoois/análise , Fermentação
15.
Sci Rep ; 14(1): 5819, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461310

RESUMO

Monitoring and predicting the regional groundwater storage (GWS) fluctuation is an essential support for effectively managing water resources. Therefore, taking Shandong Province as an example, the data from Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) is used to invert GWS fluctuation from January 2003 to December 2022 together with Watergap Global Hydrological Model (WGHM), in-situ groundwater volume and level data. The spatio-temporal characteristics are decomposed using Independent Components Analysis (ICA), and the impact factors, such as precipitation and human activities, which are also analyzed. To predict the short-time changes of GWS, the Support Vector Machines (SVM) is adopted together with three commonly used methods Long Short-Term Memory (LSTM), Singular Spectrum Analysis (SSA), Auto-Regressive Moving Average Model (ARMA), as the comparison. The results show that: (1) The loss intensity of western GWS is significantly greater than those in coastal areas. From 2003 to 2006, GWS increased sharply; during 2007 to 2014, there exists a loss rate - 5.80 ± 2.28 mm/a of GWS; the linear trend of GWS change is - 5.39 ± 3.65 mm/a from 2015 to 2022, may be mainly due to the effect of South-to-North Water Diversion Project. The correlation coefficient between GRACE and WGHM is 0.67, which is consistent with in-situ groundwater volume and level. (2) The GWS has higher positive correlation with monthly Global Precipitation Climatology Project (GPCP) considering time delay after moving average, which has the similar energy spectrum depending on Continuous Wavelet Transform (CWT) method. In addition, the influencing facotrs on annual GWS fluctuation are analyzed, the correlation coefficient between GWS and in-situ data including the consumption of groundwater mining, farmland irrigation is 0.80, 0.71, respectively. (3) For the GWS prediction, SVM method is adopted to analyze, three training samples with 180, 204 and 228 months are established with the goodness-of-fit all higher than 0.97. The correlation coefficients are 0.56, 0.75, 0.68; RMSE is 5.26, 4.42, 5.65 mm; NSE is 0.28, 0.43, 0.36, respectively. The performance of SVM model is better than the other methods for the short-term prediction.

16.
Trials ; 25(1): 157, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429648

RESUMO

BACKGROUND: Outcome assessment in perioperative exercise trials for lung cancer is heterogeneous, often omitting those that are important and patient-relevant. This heterogeneity hinders the synthesis of evidence. To address this issue, a core outcome set, an agreed-upon standardized set of outcomes to be measured and reported, is required to reduce heterogeneity among outcome measurements. This study protocol describes the methodology, aiming to develop a core outcome set for perioperative exercise intervention trials for lung cancer in clinical practice. METHODS: The project will follow the standard methodology recommended by the Core Outcome Measures in Effectiveness Trials (COMET) initiative, which is divided into four steps. Stage I: Conducting a scoping review of outcomes reported in clinical trials and protocols to develop a list of potential outcome domains. Stage II: Conducting semi-structured interviews to obtain important outcomes for patients. Stage III: Choosing the most important outcomes by conducting two rounds of the Delphi exercise. Stage IV: Achieving a consensus in a face-to-face meeting to discuss the final core outcome set. DISCUSSION: This is the first project identified for the core outcome set of perioperative exercise trials in lung cancer, which will enhance the quality, comparability, and usability of future trials and positively impact perioperative exercise and the care of patients with lung cancer. TRIALS REGISTRATION: Core Outcome Measurement in Effectiveness Trials (COMET) Initiative database registration: https://www.comet-initiative.org/Studies/Details/2091.


Assuntos
Neoplasias Pulmonares , Humanos , Resultado do Tratamento , Neoplasias Pulmonares/cirurgia , Técnica Delfos , Determinação de Ponto Final , Avaliação de Resultados em Cuidados de Saúde/métodos , Projetos de Pesquisa , Literatura de Revisão como Assunto
17.
Virology ; 594: 110016, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38461619

RESUMO

Recent ICTV taxonomy updates significantly changed phage taxonomy, yet a thorough phage classification workflow doesn't exist. This study compares six categorization tools and establishes a novel multi-method approach, combining genome similarity and specialized protein analysis. Applying the method to APEC phage P151 showed consistent categorization across platforms. A possible workflow for phage classification is proposed; offering a versatile tool for phage research and development.


Assuntos
Bacteriófagos , Bacteriófagos/genética , Genoma Viral
18.
Environ Sci Technol ; 58(14): 6284-6295, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38488464

RESUMO

The anammox dynamic membrane bioreactor (DMBR) is promising in applications with enhanced anammox biomass enrichment and fouling alleviation. However, the metabolic mechanism underlying the functional features of anammox sludge and the biofilm membrane is still obscure. We investigated the metabolic networks of anammox sludge and membrane biofilm in the DMBR. The cooperation between anammox and dissimilatory nitrate reduction to ammonium processes favored the robust anammox process in the DMBR. The rapid bacterial growth occurred in the DMBR sludge with 1.33 times higher biomass yield compared to the MBR sludge, linked to the higher activities of lipid metabolism, nucleotide metabolism, and B vitamin-related metabolism of the DMBR sludge. The metabolism of the DMBR biofilm microbial community benefited the fouling alleviation that the abundant fermentative bacteria and their cooperation with the anammox sludge microbial community promoted organics degradation. The intensified degradation of foulants by the DMBR biofilm community was further evidenced by the active carbohydrate metabolism and the upregulated vitamin B intermediates in the biofilms of the DMBR. Our findings provide insights into key metabolic mechanisms for enhanced biomass enrichment and fouling control of the anammox DMBR, guiding manipulations and applications for overcoming anammox biomass loss in the treatment of wastewater under detrimental environmental conditions.


Assuntos
Oxidação Anaeróbia da Amônia , Esgotos , Esgotos/microbiologia , Biomassa , Reatores Biológicos/microbiologia , Metaboloma , Nitrogênio/metabolismo , Oxirredução
19.
Water Res ; 254: 121378, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38430758

RESUMO

This study delved into the efficacy of sludge digestion and the mechanisms involved in sludge destruction during the implementation of forward osmosis process for sludge thickening and digestion (FO-MSTD). Utilizing a lab-scale FO membrane reactor for the thickening and digestion of waste activated sludge (WAS), the investigation explored the effects of sludge thickening and digestion in FO-MSTD processes using draw solutions of varying concentrations. The findings underscored the significance of hydraulic retention time (HRT) as a pivotal parameter influencing the swift thickening or profound digestion of sludge. Consequently, tailoring the HRT to specific processing objectives emerged as a key strategy for achieving desired treatment outcomes. In the investigation, the use of a 1 M NaCl draw solution in the FO-MSTD process showcased enhanced thickening and digestion capabilities. This specific setup raised the concentration of mixed liquor suspended solids (MLSS) to over 30 g/L and achieved a 42.7% digestion efficiency of mixed liquor volatile suspended solids (MLVSS) within an operational timeframe of 18 days. Furthermore, the research unveiled distinct stages in the sludge digestion process of the FO-MSTD system, characterized by fully aerobic digestion and aerobic-local anaerobic co-existing digestion. In the fully aerobic digestion stage, the sludge digestion rate exhibited a steady increase, leading to the breakdown of sludge floc structures and the release of a substantial amount of nutrients into the sludge supernatant. The predominant microorganisms during this stage were typical functional microorganisms found in wastewater treatment systems. Transitioning into the aerobic-local anaerobic co-existing digestion stage, both MLSS concentration and MLVSS digestion efficiency continued to rise, accompanied by a decreasing dissolved oxygen (DO) concentration. More organic matter was released into the supernatant, and sludge microbial flocs tended to reaggregate. The localized anaerobic environment within the FO-MSTD reactor fostered an increase in the relative abundance of bacteria with nitrogen and phosphorus removal functions, thereby positively impacting the mitigation of total nitrogen (TN) and total phosphorus (TP) concentrations in the sludge supernatant. The results of this research enhance comprehension of the advanced FO-MSTD technology in the treatment of WAS.


Assuntos
Fósforo , Esgotos , Esgotos/química , Osmose , Fósforo/metabolismo , Nitrogênio , Digestão , Reatores Biológicos , Eliminação de Resíduos Líquidos/métodos
20.
Sci Bull (Beijing) ; 69(7): 885-892, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38383234

RESUMO

Vortices and bound states offer an effective means of comprehending the electronic properties of superconductors. Recently, surface-dependent vortex core states have been observed in the newly discovered kagome superconductors CsV3Sb5. Although the spatial distribution of the sharp zero energy conductance peak appears similar to Majorana bound states arising from the superconducting Dirac surface states, its origin remains elusive. In this study, we present observations of tunable vortex bound states (VBSs) in two chemically-doped kagome superconductors Cs(V1-xTrx)3Sb5 (Tr = Ta or Ti), using low-temperature scanning tunneling microscopy/spectroscopy. The CsV3Sb5-derived kagome superconductors exhibit full-gap-pairing superconductivity accompanied by the absence of long-range charge orders, in contrast to pristine CsV3Sb5. Zero-energy conductance maps demonstrate a field-driven continuous reorientation transition of the vortex lattice, suggesting multiband superconductivity. The Ta-doped CsV3Sb5 displays the conventional cross-shaped spatial evolution of Caroli-de Gennes-Matricon bound states, while the Ti-doped CsV3Sb5 exhibits a sharp, non-split zero-bias conductance peak (ZBCP) that persists over a long distance across the vortex. The spatial evolution of the non-split ZBCP is robust against surface effects and external magnetic field but is related to the doping concentrations. Our study reveals the tunable VBSs in multiband chemically-doped CsV3Sb5 system and offers fresh insights into previously reported Y-shaped ZBCP in a non-quantum-limit condition at the surface of kagome superconductor.

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