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1.
Bioresour Technol ; 387: 129694, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37598802

RESUMEN

This study investigated the impact of mature compost input on compost quality, greenhouse gases (GHGs, i.e. methane and nitrous oxide) and ammonia emissions during chicken manure and rice husk chicken manure co-composting. The experiment used different volumes of mature compost: 10% (T1), 20% (T2), and 30% (T3) to replace rice husk chicken manure. Results showed that mature compost enhanced compost maturity by promoting the activities of Bacillus, Caldicoprobacter, Thermobifida, Pseudogracilibacillus, Brachybacterium, and Sinibacillus. Compared to CK, T1, T2, and T3 reduced NH3 emission by 32.07%, 33.64%, and 56.12%, and mitigated 14.97%, 16.57%, and 26.18% of total nitrogen loss, respectively. Additionally, T2 and T3 reduced CH4 emission by 40.98% and 62.24%, respectively. The N2O emissions were positive correlation with Lactobacillus, Pseudogracilibacillus and ammonium nitrogen (p < 0.05), while T2 reducing total greenhouse effects. Therefore, replacing rice husk chicken manure with 20% mature compost is an efficient and promising approach for composting.


Asunto(s)
Bacillaceae , Compostaje , Oryza , Animales , Gases , Pollos , Estiércol , Nitrógeno
2.
Chemosphere ; 341: 139949, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37648161

RESUMEN

The osmotic stress caused by salinity exerts severe inhibition on the process of biological nitrogen removal (BNR), leading to the deterioration of biosystems and the discharge of nitrogen with saline wastewater. Feasible strategies to solve the bottleneck in saline wastewater treatment have attracted great attention, but relevant studies to improve nitrogen transformations and enhance the salt-tolerance of biosystems in terms of microbiome engineering have not been systematically reviewed and discussed. This work attempted to provide a more comprehensive explanation of both BNR and microbiome engineering approaches for saline wastewater treatment. The effect of salinity on conventional BNR pathways, nitrification-denitrification and anammox, was summarized at cellular and metabolic levels, including the nitrogen metabolic pathways, the functional microorganisms, and the inhibition threshold of salinity. Promising nitrogen transformations, such as heterotrophic nitrification-aerobic denitrification, ammonium assimilation and the coupling of conventional pathways, were introduced and compared based on advantages and challenges in detail. Strategies to improve the salt tolerance of biosystems were proposed and evaluated from the perspective of microbiome engineering. Finally, prospects of future investigation and applications on halophilic microbiomes in saline wastewater treatment were discussed.


Asunto(s)
Desnitrificación , Microbiota , Nitrógeno/metabolismo , Nitrificación , Salinidad , Estrés Salino , Reactores Biológicos
3.
Eur J Pediatr ; 182(11): 5037-5045, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37650947

RESUMEN

Appendicitis in infants is a life-threatening condition that is seldom studied. Our purpose was to conduct a comprehensive evaluation of appendicitis in this age group. This was a multicenter retrospective study. Patients aged under one year with surgically confirmed appendicitis during January, 2010 to May, 2022 were identified from four institutional databases. The patients were grouped as neonates or older infants based on their age at the onset of symptoms associated with acute appendicitis. The study encompassed 98 infants, with median age of 66.5 (IQR, 13.8-176.0) days. Neonates were more likely to exhibit abdominal distension (64.9%) and fever (56.8%), while older infants more frequently presented with fever (88.5%) and vomiting (49.2%). Most patients (76.5%) were misdiagnosed during their initial clinical encounter, with a -rate was 3.1% (3 deaths), with neonates exhibiting a rate of 5.4%, and older infants 1.6%. Compared to older infants, neonates showed a higher incidence of appendiceal perforation (OR, 2.9; 95%CI, 1.1-8.1), mechanical ventilation (OR, 9.5; 95%CI, 3.1-29.2), and ICU admission (OR, 16.1; 95%CI, 5.6-45.7). However, there were no significant differences in mortality rates, 30-day readmission rates, and surgical complications between the two groups. CONCLUSION: Although most infants with appendicitis were misdiagnosed during the first clinical encounter, the observed mortality rates were considerably lower than previously reported. While neonates and infants over 28 days displayed differing clinical presentations and disease severity, their outcomes were similar. WHAT IS KNOWN: • Appendicitis in infants is a critical yet underemphasized health concern, often misdiagnosed at initial clinical encounters due to its atypical presentation and non-specific symptoms. • The mortality rates in the neonates with appendicitis was 23% during the past decades. WHAT IS NEW: • The neonates and older infants displayed differing clinical presentations and disease severity. The treatment outcomes were similar. • The mortality rate for infantile appendicitis (3.1%) was significantly lower than historically reported.


Asunto(s)
Apendicitis , Lactante , Recién Nacido , Humanos , Anciano , Apendicitis/diagnóstico , Apendicitis/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Apendicectomía
4.
Sci Total Environ ; 885: 163971, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37150466

RESUMEN

The challenge of managing agricultural phosphorus (P) in saline regions entails both reducing leaching for environmental protection and maintaining soil available P levels for crop production, which could be achieved through functional microorganisms that can facilitate P transformation processes like P assimilation, inorganic P solubilization, and organic P mineralization. In this study, we proposed an integrated utilization of phosphorus-accumulating bacteria (PAB) and phosphorus-solubilizing bacteria (PSB) to reach the goal of alleviating P leaching while improving soil available P levels. The study conducted a microcosm experiment that combined a soil column test, soil incubation, and pot experiment to evaluate the effect of bacterial inoculants on soil P leaching, soil P availability, and plant P accumulation. The results showed that the application of PAB reduced 22.6 % of dissolved P leaching through the absorption of labile phosphate in the soil, and 17.3 % of particulate P leaching through the promoted soil aggregation. The integrated inoculation of PSB and PAB synergistically improved soil available P content by 18.3 % through the mineralization of soil organic P, and remarkably boosted wheat growth and its P accumulation. Microbial community analysis revealed that the integrated microbial treatment decreased the diversity of soil bacterial community and increased the abundance of native microbial species, i.g. Lysobacter and Ramlibacter, which were positively correlated with soil available P content and alkaline phosphatase level. In conclusion, the integrated microbial strategy based on halotolerant PAB and PSB has great potential for sustainable P management in saline areas and agricultural activities.


Asunto(s)
Inoculantes Agrícolas , Fósforo , Fósforo/análisis , Suelo , Bacterias , Fosfatos/análisis
5.
J Hazard Mater ; 453: 131404, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37080026

RESUMEN

Application of bioremediation in petroleum-contaminated soils is limited by its low efficiency. Although biochar and urea are commonly used soil additives, their potential beneficial effect on the bioremediation of petroleum contamination have rarely been discussed. In this study, biochar and urea were combined to test their effects on the phytoremediation of petroleum-contaminated soil in pot experiments. Our results showed that the degradation rate of total petroleum hydrocarbons reached 49.6%, 38.3%, 42.5%, and 77.9% when the soil was treated with biochar, urea, ryegrass, and their integrated application treatment (PBCN), respectively. A number of soil physicochemical properties (e.g., pH, elements, aggregate distribution, and organic matter composition) altered by the treatments were found to be linked to the accelerated degradation of petroleum hydrocarbons. The activities of soil dehydrogenase, lipase, and urease, and the abundances of 16 s rRNA gene and alkane degradation-related genes could be increased simultaneously when biochar, urea, and ryegrass were co-applied. Furthermore, urea significantly reduced soil bacterial α-diversity, while soil bacterial community dissimilation was mainly driven by urea and ryegrass. Lysobacter, xanthomonadaceae, and longimicrobia could be biomarker species in the PBCN group. Soil bacterial network analysis showed that biochar and urea application decreased the network complexity and robustness, while ryegrass behaved inversely. Lastly, soil metabolomic analysis revealed that root soil metabolites were greatly affected by urea-addition during phytoremediation, and co-application of biochar and urea could activate the putative metabolism pathway of petroleum hydrocarbons in root soil (e.g., naphthalene and anthracene degradation, and pyruvate metabolism). In summary, this study confirmed the enhancement of biochar and urea application in the phytoremediation of petroleum-contaminated soil and explored the internal mechanism of the interactive effect, which can potentially improve the development of eco-friendly and cost-effective in-situ bioremediation technology for petroleum-contaminated soils.


Asunto(s)
Petróleo , Contaminantes del Suelo , Biodegradación Ambiental , Petróleo/metabolismo , Hidrocarburos/metabolismo , Suelo/química , Contaminantes del Suelo/metabolismo , Microbiología del Suelo
6.
Artículo en Inglés | MEDLINE | ID: mdl-36834281

RESUMEN

Composting is a promising technology for treating organic solid waste. However, greenhouse gases (methane and nitrous oxide) and odor emissions (ammonia, hydrogen sulfide, etc.) during composting are practically unavoidable, leading to severe environmental problems and poor final compost products. The optimization of composting conditions and the application of additives have been considered to mitigate these problems, but a comprehensive analysis of the influence of these methods on gaseous emissions during composting is lacking. Thus, this review summarizes the influence of composting conditions and different additives on gaseous emissions, and the cost of each measure is approximately evaluated. Aerobic conditions can be achieved by appropriate process conditions, so the contents of CH4 and N2O can subsequently be effectively reduced. Physical additives are effective regulators to control anaerobic gaseous emissions, having a large specific surface area and great adsorption performance. Chemical additives significantly reduce gaseous emissions, but their side effects on compost application must be eliminated. The auxiliary effect of microbial agents is not absolute, but is closely related to the dosage and environmental conditions of compost. Compound additives can reduce gaseous emissions more efficiently than single additives. However, further study is required to assess the economic viability of additives to promote their large-scale utilization during composting.


Asunto(s)
Compostaje , Gases de Efecto Invernadero , Gases/análisis , Compostaje/métodos , Amoníaco/análisis , Gases de Efecto Invernadero/análisis , Residuos Sólidos/análisis , Óxido Nitroso/análisis , Suelo/química
7.
Sci Total Environ ; 827: 153996, 2022 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-35189217

RESUMEN

A series of microwave biochars derived from wheat straw in the presence of a granulated activated carbon (GAC) catalyst, using a range of microwave conditions, were produced, characterized and tested as sorbents of three benzene series volatile organic compounds (VOCs). The microwave biochar with the greatest specific surface area (SSA), total pore volume (TPV), and micropore volume (312.62 m2 g-1, 0.2218 cm3 g-1, and 0.1380 cm3 g-1, respectively), were produced with 1:3 biomass:GAC catalyst mass ratio, 10 min microwave irradiation time, and at 500 W power level (WB500). Maximum adsorption capacities of WB500 to benzene, toluene and o-xylene were 53.9 mg g-1, 75.8 mg g-1 and 63.0 mg g-1, respectively, and were directly correlated to microwave biochar properties such as SSA, TPV or micropore volume, but were also influenced by VOC properties such as molecular polarity and boiling point. Kinetic modeling suggested that adsorption was governed by both physical partitioning and chemisorption mechanisms. In addition, microwave biochars maintained 79% to 92% of their initial adsorption capacity after ten adsorption/desorption cycles. These results suggest that microwave biochars produced with an GAC catalyst have excellent potential for efficient use in the removal of VOCs from waste gas.


Asunto(s)
Carbón Orgánico , Compuestos Orgánicos Volátiles , Adsorción , Benceno , Microondas
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 273: 120949, 2022 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-35183857

RESUMEN

Soil organic matter (SOM) is a key index for evaluating soil fertility and plays a vital role in the terrestrial carbon cycle. Visible and near-infrared (Vis-NIR) spectroscopy is an effective method for determining soil properties and is often used to predict SOM content. However, the key prerequisite for effective prediction of SOM content by Vis-NIR spectroscopy lies in the selection of appropriate preprocessing methods and effective data mining techniques. Therefore, in this study, six commonly used spectral preprocessing methods and effective characteristic band selection methods were selected to process the spectrum to predict SOM content. This study aims to determine a stable spectral preprocessing method and explore the predictive performance of different characteristic band selection methods. The results showed that: (i) The first derivative (FD) is the most stable spectral preprocessing method that can effectively improve the spectral characteristic information and the prediction effect of the model. (ii) The prediction effect of SOM content based on characteristic band selection methods is generally better than the full-spectra data. (iii) The precision of FD preprocessing spectrum combined with successive projections algorithm (SPA) in the partial least square regression prediction model of SOM content is the best. (iv) Although the prediction effect of the model based on the optimal band combination algorithm is slightly lower than that of SPA, it shows stable prediction performance, which provides a feasible method for SOM content prediction. In summary, the characteristic band selection method combined with FD can significantly improve the prediction accuracy of SOM content.


Asunto(s)
Suelo , Espectroscopía Infrarroja Corta , Algoritmos , Análisis de los Mínimos Cuadrados , Suelo/química , Espectroscopía Infrarroja Corta/métodos
9.
Environ Res ; 194: 110711, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33450237

RESUMEN

Humic acid can improve soil nutrients and promote plant growth. Weathered coal and lignite can be used as agricultural resources due to high humic acid content, but their impact on soil NH3 volatilization and CO2 emissions are yet to be determined. In this study, a field experiment was carried out to compare the effects of four types of humic acid isolated from coal (pulverized weathered coal (HC), pulverized lignite (HL), alkalized weathered coal (AC) and alkalized lignite (AL)) on NH3 volatilization, CO2 emissions, pH, the C/N ratio and enzyme activities in soil cultivated with maize. The effect of biotechnology humic acids (BHA) was also examined for comparison. HL, AC, AL and BHA all increased cumulative NH3 losses by 147.7, 278.5, 113.9, and 355.3%, respectively, compared with the control (chemical fertilizer only), and notably, BHA caused an increase of 90.71% compared with the humic acids isolated from coal. A significant increase in cumulative CO2 losses was observed only under AL treatment, by 14.44-24.90% compared with all other treatments. Soil urease activity was positively correlated with cumulative NH3 losses (P < 0.001), while the soil C/N ratio (P < 0.001) and soil sucrase activity (P < 0.05) were positively correlated with cumulative CO2 losses. Since humic acid from pulverized weathered coal caused no increase in NH3 volatilization or CO2 emissions, it is therefore thought to be the most suitable humic acid for field application.


Asunto(s)
Sustancias Húmicas , Suelo , Agricultura , Amoníaco/análisis , Dióxido de Carbono/análisis , Carbón Mineral , Fertilizantes/análisis , Nitrógeno , Volatilización
10.
Clin Exp Pharmacol Physiol ; 47(8): 1342-1349, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32248559

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is a common type of pancreatic cancer with one of the worst survival rate of all malignancies. Recent studies have identified that immunosuppressive B cells could employ the PD-1/PD-L1 pathway to suppress antitumour T cell responses; hence, we examined the expression and function of PD-L1 in B cells. We found that the PD-L1 expression was significantly enriched in tumour-infiltrating (TI) B cells than in peripheral blood (PB) B cells from the same patients. Additionally, the PB B cells from stage III and stage IV PDAC patients presented significantly higher PD-L1 than the PB B cells from healthy controls. High PD-L1 expression in PB B cells could be achieved by stimulation via CpG and less effectively via anti-BCR plus CD40L, but not by coculture with pancreatic cancer cell lines in vitro. Also, STAT1 and STAT3 inhibition significantly suppressed PD-L1 upregulation in stimulated B cells. CpG-stimulated PB B cells could inhibit the IFN-γ expression and proliferation of CD8 T cells in a PD-L1-dependent manner. Also, TI CD8 T cells incubated with whole TI B cells presented significantly lower IFN-γ expression and lower proliferation, than TI CD8 T cells incubated with PD-L1+  cell-depleted TI B cells, suggesting that PD-L1+  B cells could also suppress CD8 T cells in the tumour. Overall, this study identified that B cells could suppress CD8 T cells via PD-L1 expression, indicating a novel pathway of immuno-regulation in pancreatic cancer.


Asunto(s)
Antígeno B7-H1/metabolismo , Células Secretoras de Insulina/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Receptor de Muerte Celular Programada 1/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Unión Proteica
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