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1.
Waste Manag Res ; 41(1): 143-154, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35730797

RESUMO

Domestic biodegradable wastes (DBW) pose a threat to environmental quality and human health. Bioconversion via black soldier fly larvae (BSFL; Hermitia illucens L.) is an expedient way for converting 'waste to resource' (insect protein and biofertilizer). Although researches abounded in laboratory-reared experiments and bioconversion mechanisms were pertinent, the void of data from actual and full-scale operation restricts the intensification of BSFL technology and its global adoption. Hence, a full-scale BSFL bioconversion system lasting 4 years in Hangzhou (China) was investigated, and the feasibility and efficiency of 15 tonnes of DBW per day were studied. Through continuous technical optimization, the average production of fresh larvae was increased from 8.5% in 2017 to 15.3% in 2020, along with bioconversion rate of final vermicompost decreased from 35.4% to 14.5%. The total biomass reduction rate in 2020 was 68.7 ± 17.4 kg/(m3 d), equivalent to 0.735 ± 0.215 kg/(kg d) in the form of fresh larvae. Crude fat in fresh larvae accounted for 13.4%, and crude protein accounted for 16.2% in which the determined amino acid profile bore a strong resemblance to fish meal only except histidine and tyrosine. Its economic benefits proved the feasibility of this technology, and the profit reached up to 35.9 US$ per tonne of DBW in 2019. In conclusion, BSFL bioconversion system under current 'insect-farm' operation was a promising solution for DBW treatment with value-added waste recycling.


Assuntos
Dípteros , Animais , Humanos , Larva , Biomassa , China , Conservação dos Recursos Naturais
2.
Front Surg ; 9: 892562, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111236

RESUMO

Objective: This study aimed to determine the risk factors for severe lung injury (SLI) (partial pressure of oxygen/fraction of inspired oxygen <150) after radical surgery for tetralogy of Fallot with pulmonary stenosis (TOF/PS) in children. Method: A retrospective analysis was conducted including a total of 287 children with TOF/PS aged below 10 years (including 166 males) who had undergone radical surgery at the Center of Pediatric Heart Disease of the Beijing Anzhen Hospital (China) from 2018 to 2020. Results: A total of 83 cases (28.9%) had SLI after surgery. Univariate analysis showed that age, weight, pulmonary artery index (PAI), cardiopulmonary bypass (CPB) time, and polymorphonuclear leukocyte (PMN) percentage on the first day after surgery were risk factors for postoperative SLI. Multivariate logistic regression analysis showed that PAI, PMN percentage on the first day postoperatively, and CPB time were independent risk factors for SLI after surgery. The prediction model was established as follows: Logit(P) = 2.236 + 0.009*CPB-0.008*PAI-0.035*PMN, area under the curve (AUC) = 0.683, P < 0.001, sensitivity 65.8%, and specificity 68.6%. Following surgery, static lung compliance was significantly lower in the SLI group compared with the routine group. Complication rates and mortality were significantly higher in the SLI than in the routine group. Ventilator support times, the length of intensive care unit stays, and the total lengths of hospital stay were significantly longer in the SLI than in the routine group. Conclusion: The occurrence of SLI following radical surgery for TOF in children significantly affected postoperative recovery, and PAI, PMN percentage on the first day postoperatively, and CPB time were independent risk factors for SLI.

3.
Waste Manag ; 142: 55-64, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35176599

RESUMO

Black soldier fly larvae (Hermetia illucens L. BSFL) bioconversion is a promising biotechnology for food waste treatment. However, the separated residues still do not meet criteria for use as land application biofertilizers. In this work, we investigated a full-scale BSFL bioconversion project to explore features of dissolved organic matter (DOM) and its associated responses of bacterial community succession in residue during secondary composting. Data showed that the concentrations of total nitrogen and ammonium nitrogen decreased by 11.8% and 22.6% during the secondary composting, respectively, while the nitrate nitrogen concentration increased 18.7 times. The DOM concentration decreased by 69.1%, in which protein-like, alcohol-phenol, and biodegradable aliphatic substances were metabolized by bacteria during the thermophilic phase together with the accumulation of humus-like substances, resulting in an increase in the relative concentration of aromatic compounds. The structure of the bacterial community varied at different stages of the bioprocess, in which Bacteroidetes, Actinobacteria, Proteobacteria, and Firmicutes were the dominant bacterial phyla. Lysinibacillus, Pusillimonas, and Caldicoprobacter were found to be key contributors in the degradation and formation of DOM. The DOM concentration (33.4%) and temperature (17.7%) were the prime environmental factors that promoted succession of the bacterial community. Through bacterial metabolism, the structural stability of DOM components was improved during the composting process, and the degrees of humification and aromaticity were also increased. This study depicted the dynamic features of DOM and the associated bacterial community succession in residue during secondary composting, which is conducive with the reuse of BSFL residue as biofertilizer for agriculture.


Assuntos
Compostagem , Dípteros , Eliminação de Resíduos , Animais , Bactérias , Matéria Orgânica Dissolvida , Alimentos , Larva
4.
J Zhejiang Univ Sci B ; 6(3): 175-81, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15682501

RESUMO

Optically active form of alpha-cyano-3-phenoxybenzyl (CPB) alcohol, building block of pyrethroid insecticides, was synthesized as its acetate by the combination of anion-exchange resin (D301)-catalyzed transcyanation between m-phenoxybenzaldehyde (m-PBA) and acetone cyanohydrin (AC), and lipase (from Alcaligenes sp.)-catalyzed enantioselective transesterification of the resulting cyanohydrin with vinyl acetate. Through optimizing technological conditions, the catalyzing efficiency was improved considerably compared to methods previously reported. Concentrations of CPB acetate were determined by gas chromatograph. The enantio excess (e.e.) values of CPB acetate were measured by NMR (nuclear magnetic resonance) method. Effects of solvents and temperatures on this reaction were studied. Cyclohexane was shown to be the best solvent among the three tested solvents. 55 degrees C was the optimal temperature for higher degree of conversion. External diffusion limitation was excluded by raising the rotational speed to 220 r/min. However, internal diffusion could not be ignored, since the catalyst (lipase) was an immobilized enzyme and its particle dimension was not made small enough. The reaction rate was substantially accelerated when the reactant (m-PBA) concentration was as high as 249 mmol/L, but decreased when the initial concentration of m-PBA reached to 277 mmol/L. It was also found that the catalyzing capability of recovered lipase was high enough to use several batches. Study of the mole ratio of AC to m-PBA showed that 2:1 was the best choice. The strategy of adding base catalyst D301 was found to be an important factor in improving the degree of conversion of the reaction from 20% to 80%. The highest degree of conversion of the reaction has reached up to 80%.


Assuntos
Alcaligenes/enzimologia , Benzaldeídos/química , Técnicas de Química Combinatória/métodos , Lipase/química , Nitrilas/química , Éteres Fenílicos/síntese química , Tecnologia Farmacêutica/métodos , Compostos Orgânicos/química
5.
J Environ Sci (China) ; 16(5): 847-50, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15559826

RESUMO

The fate of the litter of dominant vegetation(willows and reeds) is one of the aspects studied in the frame of the project "Onderzoek Milieu Effecten Sigmaplan". One of the questions to be considered is how long the litter stays within the estuary. In this paper, the time the leaf litter (Salix triandra and Phragmites australis) stayed in the Schelde estuary was studied by using plant pigment as biomarkers with HPLC application. After analyzing the original data from the incubation experiment described by Dubuison and Geers (1999), the decomposition dynamics patterns of pigments were analyzed and described, and these decomposition dynamics patterns were used as calibration patterns. By using Spearman Rank Order Correlation, the calibration patterns of the pigments which were significant (p < 0.05) were grouped. In this way, several groups of the calibration patterns of pigment decomposition were achieved. The presence or absence of these groups of pigments (whether they can be detected or not from HPLC) was shown to be useful in determining the time the litter has stayed in the water. Combining data of DW and POC, more precise timing can be obtained.


Assuntos
Ecossistema , Modelos Biológicos , Pigmentos Biológicos/isolamento & purificação , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão , Pigmentos Biológicos/análise , Poaceae/química , Salix/química
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