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1.
RSC Adv ; 14(29): 20595-20603, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38946764

RESUMEN

The operation of the Cansolv tail gas treatment device in natural gas plants generates acidic and alkaline wastewater from the venturi unit and amine purification unit (APU), respectively. The APU wastewater is complex in composition and contains hard-to-degrade organic matter, which can adversely impact the normal functioning of the water treatment system. This study assesses the efficacy of three ozone-based advanced oxidation processes (ozone (O3), ozone/hydrogen peroxide (O3/H2O2), and ozone/Fenton (O3/Fenton)) for treating Cansolv wastewater, with chemical oxygen demand (COD) and total organic carbon (TOC) serving as indicators of organic degradation. The findings demonstrate that all three processes effectively eliminate coloration and reducible sulfur, with O3/Fenton exhibiting superior performance in removing organic substances. The treated wastewater has a clarified light-yellow appearance with residual COD levels at 43 mg L-1. Under the optimum Fenton oxidation conditions (initial pH 5, H2O2 dosage 97.8 mmol L-1, FeSO4·7H2O dosage 550 mg L-1), average TOC and COD removal rates reached 50% and 97%, respectively. After a treatment duration of 60 minutes, the wastewater demonstrated an enhanced membrane-specific flux, confirming the effectiveness of the O3/Fenton oxidation process in mitigating membrane fouling while ensuring the stable operation of the wastewater treatment system.

2.
Sci Total Environ ; 930: 172788, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38677431

RESUMEN

Cultivation alters soil aggregation, microbial compositions and the potential for carbon sequestration in cropland soils. However, the specific effects of long-term cultivation and the underlying mechanisms on soil organic carbon (SOC) storage at different aggregate sizes remain poorly understood. We characterized the dynamics of SOC storage in macroaggregates (>0.25 mm) and microaggregates (<0.25 mm) across four paddy soils successively cultivated for 60, 100, 125, and 150 years. Microbial community compositions, network patterns, enzyme activities and carbon use efficiency (CUE) were examined to elucidate the underlying microbial pathways governing SOC storage. The results showed that prolonged cultivation led to an average reduction of 45 % in SOC storage, particularly in macroaggregates. Partial least squares path modeling revealed that shifts in microorganisms in macroaggregates explained almost 80 % of the variation in SOC storage. Specifically, variations in fungal composition and decreased complexity of microbial interaction networks were strongly correlated with SOC storage. Fungal community and microbial interactions also indirectly affected SOC storage by positively correlating with extracellular enzyme activity. Moreover, bacterial composition indirectly regulated SOC storage by positively correlating with carbon use efficiency. Our findings indicated that the macroaggregate-associated microbial interactions and the metabolism activities had significant implications for SOC sequestration in paddy fields. We suggest that implementation of management practices targeted at improvement of these microbial attributes could enhance agroecosystems sustainability.


Asunto(s)
Agricultura , Secuestro de Carbono , Carbono , Microbiología del Suelo , Suelo , Suelo/química , Carbono/metabolismo , Agricultura/métodos , Microbiota
3.
J Environ Manage ; 348: 119355, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37857222

RESUMEN

Shale gas flowback water (SGFW), which is an inevitable waste product generated after hydraulic fracturing during development, poses a severe threat to the environment and human health. Managing high-salinity wastewater with complex physicochemical compositions is critical for ensuring environmental sustainability of shale gas development. Desalination processes have been recommended to treat SGFW to adhere to the discharge limits. However, organic fouling has become a significant concern in the steady operation of desalination processes, and the effective removal of organic compounds is challenging. This study aimed to develop an effective oxidation method to mitigate membrane fouling in real SGFW treatment process. It adopted the peroxymonosulfate (PMS)/ferrate (Fe(VI)) process, involving both free and non-free radical pathways that can alleviate the negative effects of high-salinity environments on oxidation. The operating parameters were optimized and removal effects were examined, while the synergistic oxidation mechanism and organic conversion of the PMS/Fe(VI) process were also analyzed. The results showed that the PMS/Fe(VI) process exhibited a synergistic effect compared with the PMS and Fe(VI) processes alone, with a total organic carbon (TOC) removal efficiency of 46.8% under optimal reaction conditions in real SGFW. In the Fe(VI)/PMS process, active species such as Fe(V)/Fe(IV), ·OH, and SO4-· were jointly involved in the oxidation of organic matter. Additionally, 99.5% of the total suspended solids and 95.2% of Ba2+ in the SGFW were removed owing to the formation of a coagulant (Fe3+) and SO42- during the reaction. Finally, an ultrafiltration membrane fouling experiment proved that oxidation processes can increase the membrane-specific flux and alleviate fouling resistance. This study can serve as a reference for the design of real SGFW treatment processes and is significant for the environmental management of shale gas development.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Humanos , Gas Natural , Membranas Artificiales , Purificación del Agua/métodos , Oxidación-Reducción
4.
Cell Death Dis ; 14(7): 481, 2023 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-37516739

RESUMEN

Although metabolic reprogramming is characterized as a hallmark of aging, implications of the crucial glutamate dehydrogenase (GDH) in human senescence remain poorly understood. Here, we report that GDH activity is significantly increased in aged mice and senescent human diploid fibroblasts. This enzymatic potentiation is associated with de-repression of GDH from its functionally suppressive ADP-ribosylation modification catalyzed by NAD-dependent ADP-ribosyltransferase/deacetylase SIRT4. A series of transcription analyses led to the identification of FOXQ1, a forkhead family transcription factor (TF), responsible for the maintenance of SIRT4 expression levels in juvenile cells. However, this metabolically balanced FOXQ1-SIRT4-GDH axis, is shifted in senescence with gradually decreasing expressions of FOXQ1 and SIRT4 and elevated GDH activity. Importantly, pharmaceutical inhibition of GDH suppresses the aberrantly activated transcription of IL-6 and IL-8, two major players in senescence-associated secretory phenotype (SASP), and this action is mechanistically associated with erasure of the repressive H3K9me3 (trimethylation of lysine 9 on histone H3) marks at IL-6 and IL-8 promoters, owing to the requirement of α-ketoglutaric acid (α-KG) from GDH-mediated glutamate dehydrogenase reaction as a cofactor for histone demethylation. In supplement with the phenotypic evidence from FOXQ1/SIRT4/GDH manipulations, these data support the integration of metabolism alterations and epigenetic regulation in driving senescence progression and highlight the FOXQ1-SIRT4-GDH axis as a novel druggable target for improving human longevity.


Asunto(s)
Glutamato Deshidrogenasa , Sirtuinas , Humanos , Animales , Ratones , Epigénesis Genética , Interleucina-6 , Interleucina-8 , Factores de Transcripción Forkhead/genética , Fenotipo , Poli(ADP-Ribosa) Polimerasas , Proteínas Mitocondriales , Sirtuinas/genética
5.
Front Microbiol ; 13: 1038536, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36452934

RESUMEN

Soil aggregates provide spatially heterogeneous microhabitats that support the coexistence of soil microbes. However, there remains a lack of detailed assessment of the mechanism underlying aggregate-microbiome formation and impact on soil function. Here, the microbial assemblages within four different aggregate sizes and their correlation with microbial activities related to nutrient cycling were studied in rice fields in Southern China. The results show that deterministic and stochastic processes govern bacterial and fungal assemblages in agricultural soil, respectively. The contribution of determinism to bacterial assemblage improved as aggregate size decreased. In contrast, the importance of stochasticity to fungal assemblage was higher in macroaggregates (>0.25 mm in diameter) than in microaggregates (<0.25 mm). The association between microbial assemblages and nutrient cycling was aggregate-specific. Compared with microaggregates, the impacts of bacterial and fungal assemblages on carbon, nitrogen, and phosphorus cycling within macroaggregates were more easily regulated by soil properties (i.e., soil organic carbon and total phosphorus). Additionally, soil nutrient cycling was positively correlated with deterministic bacterial assemblage but negatively correlated with stochastic fungal assemblage in microaggregates, implying that bacterial community may accelerate soil functions when deterministic selection increases. Overall, our study illustrates the ecological mechanisms underlying the association between microbial assemblages and soil functions in aggregates and highlights that the assembly of aggregate microbes should be explicitly considered for revealing the ecological interactions between agricultural soil and microbial communities.

6.
Microbiome ; 10(1): 245, 2022 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-36581858

RESUMEN

BACKGROUND: The early life gut microbiome is crucial in maintaining host metabolic and immune homeostasis. Though neonates with critical congenital heart disease (CCHD) are at substantial risks of malnutrition and immune imbalance, the microbial links to CCHD pathophysiology remain poorly understood. In this study, we aimed to investigate the gut microbiome in neonates with CCHD in association with metabolomic traits. Moreover, we explored the clinical implications of the host-microbe interactions in CCHD. METHODS: Deep metagenomic sequencing and metabolomic profiling of paired fecal samples from 45 neonates with CCHD and 50 healthy controls were performed. The characteristics of gut microbiome were investigated in three dimensions (microbial abundance, functionality, and genetic variation). An in-depth analysis of gut virome was conducted to elucidate the ecological interaction between gut viral and bacterial communities. Correlations between multilevel microbial features and fecal metabolites were determined using integrated association analysis. Finally, we conducted a subgroup analysis to examine whether the interactions between gut microbiota and metabolites could mediate inflammatory responses and poor surgical prognosis. RESULTS: Gut microbiota dysbiosis was observed in neonates with CCHD, characterized by the depletion of Bifidobacterium and overgrowth of Enterococcus, which was highly correlated with metabolomic perturbations. Genetic variations of Bifidobacterium and Enterococcus orchestrate the metabolomic perturbations in CCHD. A temperate core virome represented by Siphoviridae was identified to be implicated in shaping the gut bacterial composition by modifying microbial adaptation. The overgrowth of Enterococcus was correlated with systemic inflammation and poor surgical prognosis in subgroup analysis. Mediation analysis indicated that the overgrowth of Enterococcus could mediate gut barrier impairment and inflammatory responses in CCHD. CONCLUSIONS: We demonstrate for the first time that an aberrant gut microbiome associated with metabolomic perturbations is implicated in immune imbalance and adverse clinical outcomes in neonates with CCHD. Our data support the importance of reconstituting optimal gut microbiome in maintaining host metabolic and immunological homeostasis in CCHD. Video Abstract.


Asunto(s)
Microbioma Gastrointestinal , Cardiopatías Congénitas , Recién Nacido , Humanos , Microbioma Gastrointestinal/genética , Multiómica , Inflamación , Bacterias , Disbiosis/microbiología
7.
PeerJ ; 10: e13341, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35505678

RESUMEN

In this study, the effect of strip clear-cutting on the natural regeneration performance of mature Pinus tabuliformis plantations in the three locations in western part of the Liaoning Province was analyzed. Strip clear-cutting, with clear-cut and uncut strip widths of 15, 20, 25 m, and 10 and 18 m, respectively, was conducted in spring 2014, and control, in each study location. Field investigations were conducted in 2017. Fifteen sample plots with sizes of 4 m2 (2 m × 2 m) were established in each clear-cut strip, uncut strip, and control. One to four saplings were randomly selected to measure the current year increment, and the lengths and numbers for branch of the first whorl. Three saplings were randomly selected from the center of the strip to measure the photosynthetic rate. Three sample plots with sizes of 4 m2 (2 m × 2 m) and 1 m2 (1 m × 1 m) were developed in each strip and control to determine the biodiversity of shrubs and herbs as well as the water content of the decomposition and semi-decomposition layer. The results show that the current year increment and branch length of the first whorl can be ordered as follows: clear-cut strips > control > uncut strips. Number of the branches of the first whorl can be ordered as follows: clear-cut strips > uncut strips > control. Strip clear-cutting was a statistically significant treatment for the current year increment and length and number of branches of the first whorl. The saplings from the clear-cut strip with a width of 25 m have the largest photosynthetic capacity compared with those from the other strips and control. The transpiration rates of the large, medium, and small saplings from clear-cut strips are the largest and those of saplings from the control are the smallest. The water content of the decomposition and semi-decomposition layer in the control is the highest, but no significant difference was confirmed between the strip clear-cutting approaches.


Asunto(s)
Pinus , China , Agua , Biodiversidad , Estaciones del Año
8.
Int J Equity Health ; 19(1): 211, 2020 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-33246458

RESUMEN

BACKGROUND: Jiangsu was one of the first four pilot provinces to engage in comprehensive health care reform in China, which has been on-going for the past 5 years. This study aims to evaluate the equity, efficiency and productivity of health care resource allocation in Jiangsu Province using the most recent data, analyse the causes of deficiencies, and discuss measures to solve these problems. METHODS: Data were extracted from the Jiangsu Health/Family Planning Statistical Yearbook (2015-2019) and Jiangsu Statistical Yearbook (2015-2019). The Gini coefficient (G), Theil index (T) and health resource density index (HRDI) were chosen to study the fairness of health resource allocation in Jiangsu Province. Data envelopment analysis (DEA) and the Malmquist productivity index (MPI) were used to analyse the efficiency and productivity of this allocation. RESULTS: From 2014 to 2018, the total amount of health resources in Jiangsu Province increased. The G of primary resource allocation by population remained below 0.15, and that by geographical area was between 0.14 and 0.28; additionally, the G of health financial resources was below 0.26, and that by geographical area was above 0.39. T was consistent with the results for G and Lorenz curves. The HRDI shows that the allocated amounts of health care resources were the highest in southern Jiangsu, except for the number of health institutions. The average value of TE was above 0.93, and the DEA results were invalid for only two cities. From 2014 to 2018, the mean TFPC in Jiangsu was less than 1, and the values exceeded 1 for only five cities. CONCLUSION: The equity of basic medical resources was better than that of financial resources, and the equity of geographical allocation was better than that of population allocation. The overall efficiency of health care resource allocation was high; however, the total factor productivity of the whole province has declined due to technological regression. Jiangsu Province needs to further optimize the allocation and increase the utilization efficiency of health care resources.


Asunto(s)
Eficiencia Organizacional , Asignación de Recursos para la Atención de Salud/organización & administración , Asignación de Recursos para la Atención de Salud/normas , Equidad en Salud/normas , China , Humanos
9.
PeerJ ; 8: e9826, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32913683

RESUMEN

The study analysed the effect of shelterwood-cut strips on the outermost crown profiles and crown characteristics of naturally regenerated Pinus tabuliformis saplings in northeastern China. A total of 49 regenerated saplings from shelterwood-cut strips and 30 from uncut strips were collected. Nonlinear quantile regression was used to develop the outermost crown profile model for the saplings from the shelterwood-cut and uncut strips. The quantile value suitable for describing the outermost crown profiles of the two types of strips was selected using nonparametric boundary regression. The difference in crown morphologies between the shelterwood-cut strips and uncut strips was compared. The results showed that with the same diameter at breast height, the crown radii of the uncut strip saplings were larger than those of the shelterwood-cut strip saplings within the range of 0.2-1.0 for the relative depth into the crown. The largest crown radius of the saplings from the uncut strips was larger than that of the saplings from the shelterwood-cut strips. The inflection points of the shelterwood-cut strip sapling crowns were larger than those of the uncut strip sapling crowns. The crown volume of the small uncut strip saplings was larger than that of the shelterwood-cut strip saplings, and the difference in crown volume decreased with increasing sapling size. The saplings in the early stage of the uncut strips showed a greater growth rate than those of the shelterwood-cut strips, but their growth rate slowed over the long term according to branch-length annual growth. The present study provides a reference for forest management strategy decision making in promoting natural regeneration.

10.
Can J Microbiol ; 65(10): 722-737, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31167083

RESUMEN

Vegetation dynamics are known to influence belowground microbial community diversity and ecosystem processes in wetlands. However, the knowledge on microbe-microbe interactions in response to vegetation changes is scarce. In this study, we investigated how bacterial and fungal community composition, as well as bacterial-fungal community interactions, altered along a vegetation gradient in the Poyang Lake wetland. Surface soil and sediment samples were collected from three vegetation zones: dense, sparse, and naked. Vegetation zones differed in terms of dominant plant species, plant diversity, and vegetation coverage. Using Illumina MiSeq sequencing and network analysis of bacteria 16S rRNA and fungal ITS genes, we found that both bacterial and fungal community profiles varied according to vegetation conditions; in particular, the dense vegetation zone facilitated higher microbial abundance and a greater fungi to bacteria ratio. Co-occurrence analysis revealed that fungi-bacteria interactions were strong on vegetated zones, especially in the dense vegetation zone. However, a weak fungi-bacteria association was observed in the naked zone. Our results indicated that aboveground vegetation may act as a hotspot for organic matter accumulation, microbial growth, and microbe-microbe interactions, whereas fungi and bacteria prefer to distribute into niches based on their own nutritional preferences and functional specificity in bare ground.


Asunto(s)
Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Microbiota , Plantas/microbiología , Humedales , Agua Dulce , Interacciones Microbianas
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