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1.
Environ Sci Technol ; 58(23): 10368-10377, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38814143

RESUMO

The insect Tenebrio molitor exhibits ultrafast efficiency in biodegrading polystyrene (PS). However, the generation and fate of nanoplastics (NPs) in the intestine during plastic biodegradation remain unknown. In this study, we investigated the biodegradation of PS microplastics (MPs) mediated by T. molitor larvae over a 4-week period and confirmed biodegradation by analyzing Δδ13C in the PS before and after biotreatment (-28.37‰ versus -24.88‰) as an effective tool. The ·OH radicals, primarily contributed by gut microbiota, and H2O2, primarily produced by the host, both increased after MP digestion. The size distribution of residual MP particles in excrements fluctuated within the micrometer ranges. PS NPs were detected in the intestine but not in the excrements. At the end of Weeks 1, 2, 3, and 4, the concentrations of PS NPs in gut tissues were 3.778, 2.505, 2.087, and 2.853 ng/lava, respectively, while PS NPs in glands were quantified at 0.636, 0.284, and 0.113 ng/lava and eventually fell below the detection limit. The PS NPs in glands remained below the detection limit at the end of Weeks 5 and 6. This indicates that initially, NPs generated in the gut entered glands, then declined gradually and eventually disappeared or possibly biodegraded after Week 4, associated with the elevated plastic-degrading capacities of T. molitor larvae. Our findings unveil rapid synergistic MP biodegradation by the larval host and gut microbiota, as well as the fate of generated NPs, providing new insights into the risks and fate associated with NPs during invertebrate-mediated plastic biodegradation.


Assuntos
Biodegradação Ambiental , Larva , Microplásticos , Poliestirenos , Tenebrio , Animais , Microplásticos/metabolismo , Tenebrio/metabolismo , Larva/metabolismo , Plásticos/metabolismo , Microbioma Gastrointestinal
2.
Environ Sci Technol ; 58(18): 7826-7837, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38653213

RESUMO

The interaction effects between the main components (proteins (P), carbohydrates (C), and lipids (L)) of protein-rich biomass during microwave-assisted pyrolysis were investigated in depth with an exploration of individual pyrolysis and copyrolysis (PC, PL, and CL) of model compounds. The average heating rate of P was higher than those of C and L, and the interactions in all copyrolysis groups reduced the max instant heating rate. The synergistic extent (S) of PC and PL for bio-oil yield was 16.78 and 18.24%, respectively, indicating that the interactions promoted the production of bio-oil. Besides, all of the copyrolysis groups exhibited a synergistic effect on biochar production (S = 19.43-28.24%), while inhibiting the gas generation, with S ranging from -20.17 to -6.09%. Regarding the gaseous products, apart from H2, P, C, and L primarily generated CO2, CO, and CH4, respectively. Regarding bio-oil composition, the interactions occurring within PC, PL, and CL exhibited a significantly synergistic effect (S = 47.81-412.96%) on the formation of N-heterocyclics/amides, amides/nitriles, and acids/esters, respectively. Finally, the favorable applicability of the proposed interaction effects was verified with microalgae. This study offers valuable insights for understanding the microwave-assisted pyrolysis of protein-rich biomass, laying the groundwork for further research and process optimization.


Assuntos
Biomassa , Micro-Ondas , Pirólise , Proteínas/química , Lipídeos/química , Carvão Vegetal/química , Carboidratos/química , Biocombustíveis
3.
Health Commun ; : 1-16, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39081194

RESUMO

Youth offer valuable insight on health communication needs and solutions in their communities. We propose youth participatory action communication research (YPACR) as a model for health campaign development that engages youth perspectives in applying systematic theory-informed communication research to addressing youth-identified health priorities. YPACR informed a series of paid high school internship programs in West Philadelphia, in which youth interns identified mental health help-seeking communication as a need among peers. In Phase 1, guided by the reasoned action approach and Hornik & Woolf method, youth interns conducted a survey measuring behavioral beliefs, normative beliefs, and control beliefs associated with mental health help-seeking, as well as trusted sources of mental health information, among local high school students. Survey results suggested control (self-efficacy) was an important message target and peers were trusted mental health information sources. In Phase 2, youth interns developed TikTok-style messages focused on strengthening control beliefs and promoting a youth-selected mental health support resource. Youth interns distributed an online survey experiment to test whether youth-created messages shown alongside resource information increased help-seeking self-efficacy compared to an information-only control. The YPACR framework contributed to youth-relevant campaign goals, study measurements, recruitment approaches, data interpretation, and message design. We discuss the benefits and challenges of this youth-driven health campaign development model and recommendations for future research.

4.
Water Sci Technol ; 89(12): 3192-3207, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39150420

RESUMO

In this study, a novel three-dimensional biofilm electrode reactor (3D-BER) with a graphene oxide (GO)-modified cathode was developed to enhance the denitrification performance of secondary effluent from wastewater treatment plants (SEWTPs). The effects of different hydraulic retention times (HRTs) and currents on the 3D-BER were explored. The results indicated that at the optimal HRT of 4 h and current of 350 mA/m2, the 3D-BER with GO-modified cathode had a higher denitrification rate (2.40 ± 0.1 mg TN/L/h) and less accumulation of intermediate products, especially with 3.34% total nitrogen (TN) molar conversion to N2O. The GO-modified cathode offered a large biocompatible specific surface area and enhanced the conductivity, which favored microbial growth and increased electron transfer efficiency and extracellular enzyme activities. Moreover, the activity of nitrite reductase increased more than that of nitrate reductase to accelerate nitrite reduction, thus facilitating the denitrification process. The proposed 3D-BER provided an effective solution to elevate tertiary denitrification in the SEWTP.


Assuntos
Biofilmes , Reatores Biológicos , Desnitrificação , Eletrodos , Grafite , Eliminação de Resíduos Líquidos , Águas Residuárias , Grafite/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Nitrogênio/química , Purificação da Água/métodos
5.
Wei Sheng Yan Jiu ; 53(3): 396-402, 2024 May.
Artigo em Chinês | MEDLINE | ID: mdl-38839594

RESUMO

OBJECTIVE: To construct the complementary food texture in infants and young children aged 6 to 23 months, and observe the acceptability of complementary food of different months old infants. METHODS: Based on the domestic and foreign guidelines, consensus and literatures on complementary feeding, and combined with the characteristics of children's growth and development in China. The complementary food texture index of 6-23 months old infants and young children was constructed. One province was selected in the south and north respectively, one city and one rural area was selected as the observation point in each province. The stratified random sampling principle was adopted in each observation point, 240 infants and young children were selected for the acceptability study. According to the food type, 12 common foods were selected to make the complementary food toolkit. The parents were instructed to make complementary food at home according to the corresponding month age, observe and record the acceptability of single/mixed complementary food feeding. RESULTS: The complementary food texture index of 6 months, 7-8 months, 9-11 months, 12-17 months, 18-23 months was constructed. Caregivers could make complementary food at the corresponding month age according to the established complementary food texture index. The acceptability of single complementary food for infants and young children aged 6-23 months was 98.3%, 98.7%, 99.8%, 96.9% and 97.5%, respectively. The acceptability of mixed complementary food for children aged 7-23 months was 98.3%, 99.6%, 93.8% and 97.5%, respectively. CONCLUSION: The complementary food texture index of different month age can be made at home, and the acceptability of different texture is good.


Assuntos
Alimentos Infantis , Fenômenos Fisiológicos da Nutrição do Lactente , Lactente , Humanos , Masculino , Feminino , China , Preferências Alimentares
6.
Small ; 19(33): e2300253, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37093194

RESUMO

Due to substantial consumption and widespread contamination of the available freshwater resources, green, economical, and sustainable water recycling technologies are urgently needed. Recently, Faradic capacitive deionization (CDI), an emerging desalination technology, has shown great desalination potential due to its high salt removal ability, low consumption, and hardly any co-ion exclusion effect. However, the ion removal mechanisms and structure-property relationships of Faradic CDI are still unclear. Therefore, it is necessary to summarize the current research progress and challenges of Faradic CDI. In this review, the recent progress of Faradic CDI from five aspects is systematically reviewed: cell architectures, desalination mechanisms, evaluation indicators, operation modes, and electrode materials. The working mechanisms of Faradic CDI are classified as insertion reaction, conversion reaction, ion-redox species interaction, and ion-redox couple interaction in the electrolytes. The intrinsic and desalination properties of a series of Na+ and Cl- capturing materials are described in detail in terms of design concepts, structural analysis, and synthesis modulation. In addition, the effects of different cell architectures, operation modes, and electrode materials on the desalination performance of Faradic CDI are also investigated. Finally, the work summarizes the challenges remaining in Faradic CDI and provides the prospects and directions for future development.

7.
Environ Sci Technol ; 57(40): 15099-15111, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37751481

RESUMO

It remains unknown whether plastic-biodegrading macroinvertebrates generate microplastics (MPs) and nanoplastics (NPs) during the biodegradation of plastics. In this study, we utilized highly sensitive particle analyzers and pyrolyzer-gas chromatography mass spectrometry (Py-GCMS) to investigate the possibility of generating MPs and NPs in frass during the biodegradation of polystyrene (PS) and low-density polyethylene (LDPE) foams by mealworms (Tenebrio molitor larvae). We also developed a digestive biofragmentation model to predict and unveil the fragmentation process of ingested plastics. The mealworms removed 77.3% of ingested PS and 71.1% of ingested PE over a 6-week test period. Biodegradation of both polymers was verified by the increase in the δ13C signature of residual plastics, changes in molecular weights, and the formation of new oxidative functional groups. MPs accumulated in the frass due to biofragmentation, with residual PS and PE exhibiting the maximum percentage by number at 2.75 and 7.27 µm, respectively. Nevertheless, NPs were not detected using a laser light scattering sizer with a detection limit of 10 nm and Py-GCMS analysis. The digestive biofragmentation model predicted that the ingested PS and PE were progressively size-reduced and rapidly biodegraded, indicating the shorter half-life the smaller plastic particles have. This study allayed concerns regarding the accumulation of NPs by plastic-degrading mealworms and provided critical insights into the factors controlling MP and NP generation during macroinvertebrate-mediated plastic biodegradation.


Assuntos
Poliestirenos , Tenebrio , Animais , Polietileno , Tenebrio/metabolismo , Plásticos , Larva/metabolismo , Biodegradação Ambiental , Microplásticos
8.
Environ Sci Technol ; 57(47): 18940-18949, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37207368

RESUMO

Peracetic acid (PAA) is an emerging alternative disinfectant for saline waters; HOBr or HOCl is known as the sole species contributing to halogenation reactions during PAA oxidation and disinfection. However, new results herein strongly indicated that the brominating agents (e.g., BrCl, Br2, BrOCl, and Br2O) are generated at concentrations typically lower than HOCl and HOBr but played significant roles in micropollutants transformation. The presence of Cl- and Br- at environmentally relevant levels could greatly accelerate the micropollutants (e.g., 17α-ethinylestraiol (EE2)) transformation by PAA. The kinetic model and quantum chemical calculations collectively indicated that the reactivities of bromine species toward EE2 follow the order of BrCl > Br2 > BrOCl > Br2O > HOBr. In saline waters with elevated Cl- and Br- levels, these overlooked brominating agents influence bromination rates of more nucleophilic constituents of natural organic matter and increase the total organic bromine. Overall, this work refines our knowledge regarding the species-specific reactivity of brominating agents and highlights the critical roles of these agents in micropollutant abatement and disinfection byproduct formation during PAA oxidation and disinfection.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Bromo , Ácido Peracético , Águas Residuárias , Bromatos , Desinfecção/métodos , Purificação da Água/métodos
9.
Environ Res ; 220: 115162, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36580982

RESUMO

A clear understanding of algal cell adhesion and cake layer evolution in algal-related membrane processes (ARMPs) is urgently required to mitigate the membrane fouling. In this study, the effect of microparticles (10 µm-30 µm), subvisible particles (0.45 µm-10 µm), and ultrafine particles (50 kDa-0.45 µm) on the membrane fouling were explored based on the filtration performance through Hermia models, thermodynamic analysis, and simulation of extended discrete element method (EDEM). The results illustrated that microparticles played an important role in algal cell aggregation and the formation of initial clusters. Intermediate blocking fouling occurred when filtrating the subvisible particle, which facilitated internal adhesion and enhanced biofilm formation. In addition, the interfacial attractive force for the initial algal adhesion was obviously increased when the membrane surfaces were in high concentration of protein and polysaccharide. Moreover, the EDEM simulation demonstrated that subsequent particles, particularly the particles with small sizes, preferred to occupy the spaces among the previously deposited particles. This study provided new insights into the contributions of size-fractioned particles to initial fouling and their influence on the successive adhesion of other contaminants.


Assuntos
Incrustação Biológica , Purificação da Água , Adesão Celular , Filtração/métodos , Termodinâmica , Sementes
10.
J Nanobiotechnology ; 21(1): 145, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37127609

RESUMO

Colon-targeted oral drug delivery systems (CDDSs) are desirable for the treatment of ulcerative colitis (UC), which is a disease with high relapse and remission rates associated with immune system inflammation and dysregulation localized within the lining of the large bowel. However, the success of current available approaches used for colon-targeted therapy is limited. Budesonide (BUD) is a corticosteroid drug, and its rectal and oral formulations are used to treat UC, but the inconvenience of rectal administration and the systemic toxicity of oral administration restrict its long-term use. In this study, we designed and prepared colon-targeted solid lipid nanoparticles (SLNs) encapsulating BUD to treat UC by oral administration. A negatively charged surfactant (NaCS-C12) was synthesized to anchor cellulase-responsive layers consisting of polyelectrolyte complexes (PECs) formed by negatively charged NaCS and cationic chitosan onto the SLNs. The release rate and colon-specific release behavior of BUD could be easily modified by regulating the number of coated layers. We found that the two-layer BUD-loaded SLNs (SLN-BUD-2L) with a nanoscale particle size and negative zeta potential showed the designed colon-specific drug release profile in response to localized high cellulase activity. In addition, SLN-BUD-2L exhibited excellent anti-inflammatory activity in a dextran sulfate sodium (DSS)-induced colitis mouse model, suggesting its potential anti-UC applications.


Assuntos
Celulases , Colite Ulcerativa , Colite , Nanopartículas , Animais , Camundongos , Colite Ulcerativa/tratamento farmacológico , Budesonida , Colo , Colite/induzido quimicamente , Celulases/uso terapêutico , Modelos Animais de Doenças
11.
J Environ Manage ; 344: 118691, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37536239

RESUMO

Incineration is a promising disposal method for sewage sludge (SS), enriching more than 90% of phosphorus (P) in the influent into the powdered product, sewage sludge ash (SSA), which is convenient for further P recovery. Due to insufficient bioavailable P and enriched heavy metals (HMs) in SSA, it is limited to be used directly as fertilizer. Hence, this paper provides an overview of P transformation in SS incineration, characterization of SSA components, and wet-chemical and thermochemical processes for P recovery with a comprehensive technical, economic, and environmental assessment. P extraction and purification is an important technical step to achieve P recovery from SSA, where the key to all technologies is how to achieve efficient separation of P and HMs at a low economic and environmental cost. It can be clear seen from the review that the economics of P recovery from SSA are often weak due to many factors. For example, the cost of wet-chemical methods is approximately 5∼6 €/kg P, while the cost of recovering P by thermochemical methods is about 2∼3 €/kg P, which is slightly higher than the current P fertilizer (1 €/kg P). So, for now, legislation is significant for promoting P recovery from SSA. In this regard, the relevant experience in Europe is worth learning from countries that have not yet carried out P recovery from SSA, and to develop appropriate policies and legislation according to their own national conditions.


Assuntos
Metais Pesados , Fósforo , Fósforo/análise , Esgotos/química , Fertilizantes , Incineração , Europa (Continente) , Metais Pesados/química
12.
J Environ Manage ; 345: 118818, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37633102

RESUMO

It is widely understood that microplastics (MPs) can induce various biological stresses in macroinvertebrates that are incapable of biodegrading plastics. However, the biodegradation and physiological responses of plastic-degrading macroinvertebrates toward MPs of different degradability levels remain unexplored. In this study, Tenebrio molitor larvae (mealworms) were selected as a model of plastics-degrading macroinvertebrate, and were tested against three common plastics of different degradability rankings: polyvinyl chloride (PVC), polystyrene (PS), and polylactic acid (PLA) MPs (size <300 µm). These three MPs were biodegraded with the rate sequence of PLA > PS > PVC, resulting in a reversed order of negative physiological responses (body weight loss, decreased survival, and biomass depletion) of mealworms. Simultaneously, the levels of reactive oxygen species (ROS), antioxidant enzyme activities, and lipid peroxidation were uniformly increased as polymer degradability decreased and intermediate toxicity increased. PVC MPs exhibited higher toxicity than the other two polymers. The oxidative stresses were effectively alleviated by supplementing co-diet bran. The T. molitor larvae fed with PLA plus bran showed sustainable growth without an increase in oxidative stress. The results provide new insights into the biotoxicity of MPs on macroinvertebrates and offer comprehensive information on the physiological stress responses of plastic-degrading macroinvertebrates during the biodegradation of plastics with different degradability levels.


Assuntos
Poliestirenos , Tenebrio , Animais , Poliestirenos/toxicidade , Larva/metabolismo , Tenebrio/metabolismo , Plásticos , Microplásticos/toxicidade , Microplásticos/metabolismo , Cloreto de Polivinila , Poliésteres/metabolismo , Antioxidantes/metabolismo
13.
Wei Sheng Yan Jiu ; 52(3): 412-417, 2023 May.
Artigo em Chinês | MEDLINE | ID: mdl-37500520

RESUMO

OBJECTIVE: To establish a set of visualization systems suitable for displaying the transition of malnutrition status in different population across time and space in China. METHODS: Based on the data characteristics of the four monitoring systems, including the China Nutrition and Health Surveillance, the China Health and Nutrition Survey, the Project of Children Nutrition Improvement in Poor Rural Regions, and the Nutrition Improvement Program for Rural Compulsory Education Students, to be merged and the requirements of this project, the client/server architecture(C/S architecture) application mode was adopted, the Visual Studio 2019 development tool set, Python 3.7-10 and C # 8.0 language programming were used for data integration, and a complete set of data preprocessing, data conversion and data integration calculation processes were established. RESULTS: The malnutrition visualization system provided a visualization display system for the nutritional status of different populations under the multi database fusion index system based on the integrated malnutrition database. The system was able to not only modify, delete and update data, but query, display and analyze malnutrition conditions including growth retardation, low weight, emaciation, micronutrient deficiency, overweight, and obesity. CONCLUSION: Malnutrition visualization system dynamically presented the time series and spatial distribution of malnutrition among Chinese residents, and explored the regional characteristics and major challenges of nutrition problems in different periods.


Assuntos
Desnutrição , Criança , Humanos , Desnutrição/epidemiologia , Estado Nutricional , Obesidade , Sobrepeso , Estudantes , Prevalência
14.
Environ Sci Technol ; 56(23): 17310-17320, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36350780

RESUMO

Biodegradation of polystyrene (PS) in mealworms (Tenebrio molitor lavae) has been identified with commercial PS foams. However, there is currently limited understanding of the influence of molecular weight (MW) on insect-mediated plastic biodegradation and the corresponding responses of mealworms. In this study, we provided the results of PS biodegradation, gut microbiome, and metabolome by feeding mealworms with high-purity PS microplastics with a wide variety of MW. Over 24 days, mealworms (50 individuals) fed with 0.20 g of PS showed decreasing removal of 74.1 ± 1.7, 64.1 ± 1.6, 64.4 ± 4.0, 73.5 ± 0.9, 60.6 ± 2.6, and 39.7 ± 4.3% for PS polymers with respective weight-average molecular weights (Mw) of 6.70, 29.17, 88.63, 192.9, 612.2, and 1346 kDa. The mealworms degraded most PS polymers via broad depolymerization but ultrahigh-MW PS via limited-extent depolymerization. The gut microbiome was strongly associated with biodegradation, but that with low- and medium-MW PS was significantly distinct from that with ultrahigh-MW PS. Metabolomic analysis indicated that PS biodegradation reprogrammed the metabolome and caused intestinal dysbiosis depending on MW. Our findings demonstrate that mealworms alter their gut microbiome and intestinal metabolic pathways in response to in vivo biodegradation of PS polymers of various MWs.


Assuntos
Microbioma Gastrointestinal , Tenebrio , Humanos , Animais , Tenebrio/metabolismo , Poliestirenos , Plásticos , Microbioma Gastrointestinal/fisiologia , Peso Molecular , Polímeros , Larva/metabolismo , Metaboloma
15.
Environ Sci Technol ; 56(2): 1300-1309, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34965096

RESUMO

Peracetic acid (PAA) is an emerging oxidant and disinfectant for wastewater (WW) treatment due to limited harmful disinfection byproduct (DBP) formation. Nitrite (NO2-) is a ubiquitous anion in water, but the impact of NO2- on PAA oxidation and disinfection has been largely overlooked. This work found for the first time that NO2- could significantly promote the oxidation of sulfonamide antibiotics (SAs) by PAA. Unexpectedly, the reactive nitrogen species (RNS), for example, peroxynitrite (ONOO-), rather than conventional organic radicals (R-O•) or reactive oxygen species (ROS), played major roles in SAs degradation. A kinetic model based on first-principles was developed to elucidate the reaction mechanism and simulate reaction kinetics of the PAA/NO2- process. Structural activity assessment and quantum chemical calculations showed that RNS tended to react with an aromatic amine group, resulting in more conversion of NO2--N to organic-N. The formation of nitrated and nitrosated byproducts and the enhancement of trichloronitromethane formation potential might be a prevalent problem in the PAA/NO2- process. This study provides new insights into the reaction of PAA with NO2- and sheds light on the potential risks of PAA in WW treatment in the presence of NO2-.


Assuntos
Ácido Peracético , Purificação da Água , Antibacterianos , Desinfecção , Nitritos , Espécies Reativas de Nitrogênio , Sulfonamidas , Purificação da Água/métodos
16.
Environ Res ; 209: 112860, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35123965

RESUMO

As the global economy develops and the population increases, greenhouse gas emissions and wastewater discharge have become inevitable global problems. Conventional wastewater treatment processes produce direct or indirect greenhouse gas, which can intensify global warming. Microalgae-based wastewater treatment technology can not only purify wastewater and use the nutrients in wastewater to produce microalgae biomass, but it can also absorb CO2 in the atmosphere or flue gas through photosynthesis, which demonstrates great potential as a sustainable and economical wastewater treatment technology. This review highlights the multifaceted roles of microalgae in different types of wastewater treatment processes in terms of the extent of their bioremediation function and microalgae biomass production. In addition, various newly developed microalgae cultivation systems, especially biofilm cultivation systems, were further characterized systematically. The performance of different microalgae cultivation systems was studied and summarized. Current research on the technical approaches for the modification of the CO2 capture by microalgae and the maximization of CO2 transfer and conversion efficiency were also reviewed. This review serves as a useful and informative reference for the application of wastewater treatment and CO2 capture by microalgae, aiming to provide a reference for the realization of carbon neutrality in wastewater treatment systems.


Assuntos
Microalgas , Biomassa , Carbono , Dióxido de Carbono , Águas Residuárias/análise
17.
Molecules ; 27(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36234920

RESUMO

Advanced oxidation processes (AOPs) demonstrate great micropollutant degradation efficiency. In this study, CuFe2O4 was successfully used to activate peracetic acid (PAA) to remove Rhodamine B. Acetyl(per)oxyl radicals were the dominant species in this novel system. The addition of 2,4-hexadiene (2,4-HD) and Methanol (MeOH) significantly inhibited the degradation efficiency of Rhodamine B. The ≡Cu2+/≡Cu+ redox cycle dominated PAA activation, thereby producing organic radicals (R-O˙) including CH3C(O)O˙ and CH3C(O)OO˙, which accounted for the degradation of Rhodamine B. Increasing either the concentration of CuFe2O4 (0-100 mg/L) or PAA (10-100 mg/L) promoted the removal efficiency of this potent system. In addition, weakly acid to weakly alkali pH conditions (6-8) were suitable for pollutant removal. The addition of Humid acid (HA), HCO3-, and a small amount of Cl- (10-100 mmol·L-1) slightly inhibited the degradation of Rhodamine B. However, degradation was accelerated by the inclusion of high concentrations (200 mmol·L-1) of Cl-. After four iterations of catalyst recycling, the degradation efficiency remained stable and no additional functional group characteristic peaks were observed. Taking into consideration the reaction conditions, interfering substances, system stability, and pollutant-removal efficiency, the CuFe2O4/PAA system demonstrated great potential for the degradation of Rhodamine B.


Assuntos
Ácido Peracético , Poluentes Químicos da Água , Álcalis , Peróxido de Hidrogênio , Metanol , Oxirredução , Rodaminas
18.
Water Sci Technol ; 86(3): 511-529, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35960834

RESUMO

Nitrate loss in interflow caused serious nitrate pollution of neighboring water bodies in the purple soil region of China's Sichuan Province. In this study, Mg/Fe(Al)-calcined layered double hydroxides (Mg/Fe(Al)-CLDHs) with varied Mg/Fe(Al) ratios were synthesized for nitrate removal from interflow, and 3:1 Mg/Fe CLDH exhibited the best adsorption performance. The effects of initial pH, adsorbent dosage and co-existing anions on the adsorption performance were investigated by batch experiments. The best-fitting kinetic and isothermal models for nitrate adsorption were the pseudo-second-order model and Freundlich model, respectively, indicating that the adsorption process was a physical-chemical multilayer process. The maximum adsorption capacity of nitrate was 73.36 mg/g, which was higher than that of many other commonly used adsorbents. The adsorbents were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscope (TEM) and Brunauer-Emmett-Teller (BET) techniques, and the XRD and FT-IR results revealed that the adsorption mechanism involved original layered structure reconstruction and ion-exchange interaction. Under the coexistence of SO42- and Cl-, 75.63% nitrate in interflow could be removed after 6 h of adsorption. Overall, the synthesized Mg/Fe CLDH is an effective and low-cost nitrate adsorbent for in-situ nitrate removal.


Assuntos
Nitratos , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Hidróxidos/química , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/química
19.
Adv Funct Mater ; 31(5)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33692665

RESUMO

Macrophages are one of the most abundant non-malignant cells in the tumor microenvironment, playing critical roles in mediating tumor immunity. As important innate immune cells, macrophages possess the potential to engulf tumor cells and present tumor-specific antigens for adaptive antitumor immunity induction, leading to growing interest in targeting macrophage phagocytosis for cancer immunotherapy. Nevertheless, live tumor cells have evolved to evade phagocytosis by macrophages via the extensive expression of anti-phagocytic molecules, such as CD47. In addition, macrophages also rapidly recognize and engulf apoptotic cells (efferocytosis) in the tumor microenvironment, which inhibits inflammatory responses and facilitates immune escape of tumor cells. Thus, intervention of macrophage phagocytosis by blocking anti-phagocytic signals on live tumor cells or inhibiting tumor efferocytosis presents a promising strategy for the development of cancer immunotherapies. Here, the regulation of macrophage-mediated tumor cell phagocytosis is first summarized, followed by an overview of strategies targeting macrophage phagocytosis for the development of antitumor therapies. Given the potential off-target effects associated with the administration of traditional therapeutics (for example, monoclonal antibodies, small molecule inhibitors), we highlight the opportunity for nanomedicine in macrophage phagocytosis intervention.

20.
FEMS Yeast Res ; 21(4)2021 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-34037755

RESUMO

Yeast flocculation plays an essential role in industrial application. Appropriate flocculation of yeast cells at the end of fermentation benefits the cell separation in production, which is an important characteristic of lager yeast for beer production. Due to the complex fermentation environment and diverse genetic background of yeast strains, it is difficult to explain the flocculation mechanism and find key genes that affect yeast flocculation during beer brewing. By analyzing the genomic mutation of two natural mutant yeasts with stronger flocculation ability compared to the parental strain, it was found that the mutated genes common in both mutants were enriched in protein processing in endoplasmic reticulum, membrane lipid metabolism and other pathways or biological processes involved in stress responses. Further functional verification of genes revealed that regulation of RIM101 and VPS36 played a role in lager yeast flocculation under the brewing condition. This work provided new clues for improving yeast flocculation in beer brewing.


Assuntos
Cerveja/microbiologia , Fermentação , Floculação , Saccharomyces/genética , Evolução Molecular , Genoma Fúngico , Microrganismos Geneticamente Modificados
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