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1.
Angew Chem Int Ed Engl ; : e202406082, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807303

RESUMO

Commercial alkaline water electrolysers typically operate at 80 °C to minimize energy consumption. However, NiFe-based catalysts, considered as one of the most promising candidates for anode, encounter the bottleneck of high solubility at such temperatures. Herein, we discover that the dissolution of NiFe layered double hydroxides (NiFe-LDH) during operation not only leads to degradation of anode itself, but also deactivates cathode for water splitting, resulting in decay of overall electrocatalytic performance. Aiming to suppress the dissolution, we employed oxyanions as inhibitors in electrolyte. The added phosphates to the electrolyte inhibit the loss of NiFe-LDH active sites at 400 mA cm-2 to 1/3 of the original amount, thus reducing the rate of performance decay by 25-fold. Furthermore, the usage of borates, sulfates, and carbonates yields similar results, demonstrating the reliability and universality of the active site dissolution inhibitor, and its role in elevated water electrolysis.

2.
Angew Chem Int Ed Engl ; 62(40): e202309882, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37603411

RESUMO

The direct seawater electrolysis at high current density and low overpotential affords an effective strategy toward clean and renewable hydrogen fuel production. However, the severe corrosion of anode as a result of the saturation of Cl- upon continuous seawater feeding seriously hamper the electrolytic process. Herein, cobalt ferricyanide / cobalt phosphide (CoFePBA/Co2 P) anodes with Cap/Pin structure are synthesized, which stably catalyze alkaline saturated saline water oxidation at 200-2000 mA cm-2 over hundreds of hours without corrosion. Together with the experimental findings, the molecular dynamics simulations reveal that PO4 3- and Fe(CN)6 3- generated by the electrode play synergistic role in repelling Cl- via electrostatic repulsion and dense coverage, which reduced Cl- adsorption by nearly 5-fold. The novel anionic synergy endow superior corrosion protection for the electrode, and is expected to promote the practical application of saline water electrolysis.

3.
Small ; 18(30): e2202513, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35780475

RESUMO

Developing highly active, durable, and cost-effective electrocatalysts for the oxygen evolution reaction (OER) is of prime importance in proton exchange membrane (PEM) water electrolysis techniques. Ru-based catalysts have high activities but always suffer from severe fading and dissolution issues, which cannot satisfy the stability demand of PEM. Herein, a series of iridium-doped yttrium ruthenates pyrochlore catalysts is developed, which exhibit better activity and much higher durability than commercial RuO2 , IrO2 , and most of the reported Ru or Ir-based OER electrocatalysts. Typically, the representative Y2 Ru1.2 Ir0.8 O7 OER catalyst demands a low overpotential of 220 mV to achieve 10 mA cm-2 , which is much lower than that of RuO2 (300 mV) and IrO2 (350 mV). In addition, the catalyst does not show obvious performance decay or structural degradation over a 2000 h stability test. EXAFS and XPS co-prove the reduced valence state of ruthenium and iridium in pyrochlore contributes to the improved activity and stability. Density functional theory reveals that the potential-determining steps barrier of OOH* formation is greatly depressed through the synergy effect of Ir and Ru sites by balancing the d band center and oxygen intermediates binding ability.

4.
J Sci Food Agric ; 96(4): 1269-74, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25873008

RESUMO

BACKGROUND: Antibiotics used as growth promoters in livestock have been banned in the European Union since 2006. Alternatives of antibiotics have focused on phytogenic plants, such as herbs and medicinal plants. No studies have evaluated the use of fermented medicinal plants (FMP) made up of Gynura procumbens, Rehmannia glutinosa and Scutellaria baicalensis in weanling pigs. Therefore, an experiment was conducted to determine the effects of FMP on growth performance, nutrient digestibility, fecal noxious gas emissions and diarrhea score in weanling pigs. RESULTS: FMP supplementation increased (P < 0.05) average daily gain, average daily feed intake, gain:feed, apparent total tract digestibility of dry matter, nitrogen and gross energy compared with NC treatment, while a linear effect (P < 0.05) was observed on those criteria. Ammonia, total mercaptans and hydrogen sulfide concentrations were decreased (P < 0.05) by the supplementation of FMP compared with NC. Additionally, diarrhea score was lower (P < 0.05) by FMP addition compared with NC during days 0-7 and days 8-14. CONCLUSION: These results suggested that FMP could be used as an alternative to antibiotics by enhancing growth performance and nutrient digestibility, and decreasing fecal noxious gas emission and early diarrhea score of weanling pigs.


Assuntos
Diarreia/prevenção & controle , Digestão , Fezes/química , Fermentação , Plantas Medicinais , Doenças dos Suínos/prevenção & controle , Animais , Medicamentos de Ervas Chinesas , Sulfeto de Hidrogênio/análise , Rehmannia , Scutellaria baicalensis , Compostos de Sulfidrila/análise , Sus scrofa/crescimento & desenvolvimento , Suínos , Desmame
5.
Appl Microbiol Biotechnol ; 98(2): 969-77, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23681590

RESUMO

The sludge digestate stabilized by mesophilic anaerobic digestion was further degraded through thermophilic anaerobic digestion using 0-10 % (v/v) of thermophilic, proteolytic Coprothermobacter proteolyticus, and/or methanogenic granular sludge. The results demonstrated that the temperature shift to thermophilic condition promoted abiotic solubilization of proteins and reactivated the fermentative bacteria and methanogens indigenous in the sludge digestate, resulting in a final methane yield of 6.25 mmol-CH4/g-volatile suspended solid (VSS) digestate. The addition of C. proteolyticus accelerated the hydrolysis and fermentation of proteins and polysaccharides in the digestate during the early stage of thermophilic anaerobic digestion and stimulated methane production by syntrophic cooperation with methanogenic granular sludge. In the treatment with granular sludge and inoculated with 10 % (v/v) of C. proteolyticus, a final methane yield of 7 mmol-CH4/g-VSS digestate was obtained, and 48.4 % proteins and 27.0 % polysaccharides were degraded. The dissolved proteins were contributed by abiotic factor, C. proteolyticus, and indigenous digestate bacteria, respectively, by around 16, 28, and 56 %.


Assuntos
Bactérias Gram-Positivas/metabolismo , Metano/metabolismo , Polissacarídeos/metabolismo , Proteínas/metabolismo , Esgotos/química , Esgotos/microbiologia , Biotransformação , Hidrólise , Temperatura
6.
Nat Commun ; 15(1): 4712, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38830888

RESUMO

Low-energy consumption seawater electrolysis at high current density is an effective way for hydrogen production, however the continuous feeding of seawater may result in the accumulation of Cl-, leading to severe anode poisoning and corrosion, thereby compromising the activity and stability. Herein, CoFeAl layered double hydroxide anodes with excellent oxygen evolution reaction activity are synthesized and delivered stable catalytic performance for 350 hours at 2 A cm-2 in the presence of 6-fold concentrated seawater. Comprehensive analysis reveals that the Al3+ ions in electrode are etched off by OH- during oxygen evolution reaction process, resulting in M3+ vacancies that boost oxygen evolution reaction activity. Additionally, the self-originated Al(OH)n- is found to adsorb on the anode surface to improve stability. An electrode assembly based on a micropore membrane and CoFeAl layered double hydroxide electrodes operates continuously for 500 hours at 1 A cm-2, demonstrating their feasibility in brine electrolysis.

7.
Nat Commun ; 15(1): 1973, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38438342

RESUMO

Seawater electrolysis offers a renewable, scalable, and economic means for green hydrogen production. However, anode corrosion by Cl- pose great challenges for its commercialization. Herein, different from conventional catalysts designed to repel Cl- adsorption, we develop an atomic Ir catalyst on cobalt iron layered double hydroxide (Ir/CoFe-LDH) to tailor Cl- adsorption and modulate the electronic structure of the Ir active center, thereby establishing a unique Ir-OH/Cl coordination for alkaline seawater electrolysis. Operando characterizations and theoretical calculations unveil the pivotal role of this coordination state to lower OER activation energy by a factor of 1.93. The Ir/CoFe-LDH exhibits a remarkable oxygen evolution reaction activity (202 mV overpotential and TOF = 7.46 O2 s-1) in 6 M NaOH+2.8 M NaCl, superior over Cl--free 6 M NaOH electrolyte (236 mV overpotential and TOF = 1.05 O2 s-1), with 100% catalytic selectivity and stability at high current densities (400-800 mA cm-2) for more than 1,000 h.

8.
Sci Bull (Beijing) ; 68(6): 613-621, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36914544

RESUMO

Electrocatalytic two-electron water oxidation affords a promising approach for distributed production of H2O2 using electricity. However, it suffers from the trade-off between the selectivity and high production rate of H2O2 due to the lack of suitable electrocatalysts. In this study, single atoms of Ru were controllably introduced into titanium dioxide to produce H2O2 through an electrocatalytic two-electron water oxidation reaction. The adsorption energy values of OH intermediates could be tuned by introducing Ru single atoms, offering superior H2O2 production under high current density. Notably, a Faradaic efficiency of 62.8% with an H2O2 production rate of 24.2 µmol min-1 cm-2 (>400 ppm within 10 min) was achieved at a current density of 120 mA cm-2. Consequently, herein, the possibility of high-yield H2O2 production under high current density was demonstrated and the importance of regulating intermediate adsorption during electrocatalysis was evidenced.

9.
Zhonghua Yi Xue Za Zhi ; 91(43): 3054-7, 2011 Nov 22.
Artigo em Chinês | MEDLINE | ID: mdl-22333058

RESUMO

OBJECTIVE: To explore the potential effects of hydrogen sulfide (H(2)S) on nuclear factor kappa B (NF-κB) and intercellular adhesion molecule 1 (ICAM-1) in lung tissue with oleic acid (OA)-induced acute lung injury (ALI) in rats. METHODS: Forty-two rats were randomly divided into 3 groups: control (n = 6), OA (n = 18) and OA + NaHS (n = 18). Rats in the OA group received an intra-tail vein injection of oleic acid 0.1 ml/kg while those in the OA + NaHS group an intraperitoneal injection of NaHS 56 µmol/kg at 30 mins before OA injection. The OA and OA + NaHS groups were subdivided into 3 subgroups depending on the therapeutic duration: 2 h (n = 6), 4 h (n = 6) and 6 h (n = 6). Rats in the control group received an intra-tail vein injection of normal saline 0.1 ml/kg. Bronchioalveolar lavage fluid (BALF) was collected and the leucocytic differential count of sediment examined. The extent of lung injury was evaluated by the index of quantitative assessment (IQA). The H(2)S level in lung tissue was measured by sensitive sulphur electrode. The nuclear translocation of NF-κB and the expression of ICAM-1 in alveolar epithelial cells were measured by immunohistochemical staining. RESULTS: Compared with the control group, the BALF percentage of polymorphonuclear (PMN) cell was significantly higher at 2, 4 and 6 h in the OA-treated rats [(74.5 ± 3.0)%, (80.2 ± 2.0)%, (87.2 ± 2.7)% vs (3.1 ± 1.6)%, all P < 0.01]. And the value of IQA increased significantly versus those at 2, 4 and 6 h in the control group (5.2 ± 0.8, 6.4 ± 0.6, 6.8 ± 0.8 vs 0.4 ± 0.6, all P < 0.01). And the levels of H(2)S in lung tissue decreased at 2, 4 and 6 h [(21.20 ± 0.38) µmol/g, (20.80 ± 0.53) µmol/g, (18.92 ± 0.75) µmol/g vs (26.81 ± 0.65) µmol/g, all P < 0.01]. Moreover, the nuclear expression of NF-κB and the membranous expression of ICAM-1 in the alveolar epithelial cells in OA group rats was significantly higher than those of the control group (all P < 0.05). After the dosing of H(2)S donor (NaHS), the BALF percentage of PMN cell and the lung IQA decreased in the three subgroup rats (2, 4 and 6 h) versus the OA group. And the concentration of H(2)S increased significantly in the 4 h and 6 h subgroups versus the OA group at the corresponding time points. Simultaneously, the nuclear expression of NF-κB and the membranous expression of ICAM-1 in alveolar epithelial cells were significantly lower than that of the OA group at 4 h and 6 h subgroups (all P < 0.05). CONCLUSION: H(2)S may play a protective role in the ALI rats through the suppression of lung inflammation. And the inhibited expression of alveolar epithelial cell NF-κB mediates the anti-inflammatory effects of H(2)S.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Sulfeto de Hidrogênio/farmacologia , Molécula 1 de Adesão Intercelular/metabolismo , Pulmão/metabolismo , NF-kappa B/metabolismo , Animais , Pulmão/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
10.
Dis Markers ; 2021: 8819934, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33763157

RESUMO

Non-small-cell lung cancer (NSCLC) is one of the most common types of cancer worldwide. Accumulating evidence has suggested that aberrant expression of microRNAs (miRNAs) is involved in the carcinogenesis and progression of NSCLC. The current study is aimed at investigating the clinical significance of serum miR-629 in NSCLC. The expression levels of serum miR-629 in patients with NSCLC, patients with nonmalignant lung diseases, and healthy controls were assessed by real-time quantitative polymerase chain reaction. Our results showed that serum miR-629 levels were significantly upregulated in NSCLC patients compared to the controls. Serum miR-629 exhibited better performance for discriminating NSCLC patients from healthy controls, compared to the traditional biomarkers CYFRA 21-1 and CEA. In addition, a high serum miR-629 level was positively correlated with adverse clinicopathological parameters including lymph node metastasis, differentiation, and clinical stage. Serum miR-629 was dramatically reduced in the NSCLC cases receiving surgical treatment. Moreover, the patients in the high serum miR-629 group suffered poorer overall survival and disease-free survival than those in the low serum miR-629 group. In conclusion, serum miR-629 might serve as a potential prognostic biomarker for NSCLC.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Neoplasias Pulmonares/sangue , MicroRNAs/genética , Idoso , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Regulação para Cima
11.
Beijing Da Xue Xue Bao Yi Xue Ban ; 42(6): 708-12, 2010 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-21170104

RESUMO

OBJECTIVE: To investigate the changes of serum enzymes and their prognostic value in patients with pulmonary thromboembolism after orthopaedic surgery. METHODS: Clinical data of 134 cases of confirmed pulmonary thromboembolism after orthopaedic surgery from 1997 to 2010 were reviewed.The 134 cases were divided into dead group (n=28) and survival group (n=106). The clinical presentation, electrocardiogram, arterial oxygen pressure (PaO2), chest X-ray, echocardiography,and serum enzymes including alanine transaminase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (γ-GT), lactate dehydrogenase (LDH), creatine kinase (CK) and creatine kinase isoenzyme (CK-MB) were analyzed. And multivariable Logistic regression was conducted to identify the risk factors of in-hospital death. RESULTS: The average age of dead patients was higher than that of survival patients (P=0.043), while the P(O2) of dead patients was much lower than that of survival patients (P=0.035). The percentage of syncope, hypotension, right bundle-branch block and SIQIIITIII, pulmonary hypertension and right ventricular dysfunction in dead patients were higher than those in survival patients (P=0.009, P=0.041, P=0.018, P=0.030, P=0.042 and P=0.038), respectively. There were significant differences of elevated serum ALT, LDH and CK-MB levels between dead patients and survival patients (P=0.042, P=0.035 and P=0.017). Logistic regression indicated that the risk factors for death of patients with PTE after orthopaedic surgery were age (OR, 1.182; 95% CI, 1.010-1.383; P=0.036), hypoxemia (OR, 1.128; 95% CI, 1.018-1.249; P=0.022), hypotension (OR, 3.346; 95% CI, 1.116-10.031; P=0.031), right ventricular dysfunction (OR, 4.083; 95% CI, 1.040- 16.035; P=0.044) and elevated serum CK-MB levels (OR, 3.466; 95% CI, 1.054-11.400; P=0.041). CONCLUSION: The incidence rate of elevated serum ALT, LDH and CK-MB levels in patients who died of pulmonary thromboembolism after orthopaedic surgery was higher than that of survival patients; Age, hypoxemia, hypotension and right ventricular dysfunction were independent risk factors of in-hospital death; The CK-MB might be a useful biomarker for risk stratification of acute PTE.


Assuntos
Causas de Morte , Creatina Quinase Forma MB/sangue , Procedimentos Ortopédicos/efeitos adversos , Complicações Pós-Operatórias/prevenção & controle , Embolia Pulmonar/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Embolia Pulmonar/etiologia , Embolia Pulmonar/mortalidade , Fatores de Risco , Adulto Jovem
12.
Exp Biol Med (Maywood) ; 233(9): 1081-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18535161

RESUMO

We examined the possible role of hydrogen sulfide (H2S) in the pathogenesis of oleic acid (OA)-induced acute lung injury (ALI) and its regulatory effects on the inflammatory response. Compared to control rats, the OA-treated rats had decreased partial pressure of oxygen in the arterial blood (PaO2) levels, an increased pulmonary wet/dry weight (W/D) ratio, increased index of quantitative assessment (IQA) score and increased frequency of polymorphonuclear (PMN) cells in the lung 2, 4 or 6 h after OA injection (0.1 ml/kg, intravenous injection). In addition, significantly increased IL-6, IL-8 and IL-10 levels together with decreased H2S levels were observed in the plasma and lung tissue of OA-treated rats compared to controls. Administration of the H2S donor sodium hydrosulfide (NaHS, 56 micromol/L, intraperitoneal injection) into OA-treated rats increased the PaO2 level, reduced the lung W/D ratio and infiltration of PMN cells, and alleviated the degree of ALI (measured by the IQA score). In addition, NaHS decreased IL-6 and IL-8 levels but increased IL-10 levels in the plasma and lung tissues, suggesting that H2S may regulate the inflammatory response during ALI via regulation of IL-6, IL-8 and IL-10. Thus, the down-regulation of endogenous H2S production might be involved in the pathogenesis of OA-induced ALI in rats.


Assuntos
Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/uso terapêutico , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Líquido da Lavagem Broncoalveolar , Diferenciação Celular/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacocinética , Interleucina-10/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Masculino , Ácido Oleico/farmacologia , Ratos , Ratos Sprague-Dawley , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/patologia
13.
Anim Sci J ; 88(9): 1398-1405, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28226409

RESUMO

This study was conducted to evaluate the effects of xylanase supplementation on nutrient digestibility, growth performance, blood parameters, fecal microflora shedding, fecal score and fecal noxious gas emission of weaning pigs fed corn-soybean meal based diet. A total of 150 weaning pigs with an average initial body weight (BW) of 7.85 ± 0.93 kg were randomly allocated to three treatments based on BW and sex (10 replicate pens with five pigs, two gilts and three barrows) were used in this 42-day trial. Dietary treatments were: (1) CON, basal diet; (2) X1, basal diet +0.005% xylanase; (2) X2, basal diet +0.01% xylanase. The xylanase supplementation linearly increased (P < 0.05) average daily gain (ADG), and gain : feed ratio (G:F) from days 29 to 42 and the in overall period, dry matter, nitrogen and energy digestibility, and fecal Lactobacilli counts, and linearly decreased (P < 0.05) blood urea nitrogen (BUN) concentration, fecal NH3 and H2 S emission. Additionally, at weeks 5 and 6, there was a linear decrease in fecal score with xylanase supplementation. In conclusion, dietary supplementation of xylanase improved growth performance, nutrient digestibility, shifted microbiota by increasing fecal Lactobacillus counts, decreased BUN concentration, fecal score, and fecal NH3 and H2 S emission in weaning pigs.


Assuntos
Poluentes Atmosféricos/metabolismo , Amônia/metabolismo , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Dieta/veterinária , Suplementos Nutricionais , Digestão/fisiologia , Endo-1,4-beta-Xilanases/administração & dosagem , Fezes/química , Fezes/microbiologia , Gases , Glycine max , Sulfeto de Hidrogênio/metabolismo , Suínos/crescimento & desenvolvimento , Suínos/metabolismo , Suínos/microbiologia , Zea mays , Animais , Carga Bacteriana , Nitrogênio da Ureia Sanguínea , Metabolismo Energético , Feminino , Lactobacillus/isolamento & purificação , Masculino , Desmame
14.
Artigo em Inglês | MEDLINE | ID: mdl-26635958

RESUMO

BACKGROUND: Dietary nucleotides, considered as antibiotics alternative, were shown to have positive effects on intestinal hyperaemia, systemic immunity, small-intestinal growth, and hepatic composition in pigs. However, there is no previous research on nucleotide supplementation in weanling pigs under an oral challenged E. coli K88. Therefore, 2 experiments were conducted to investigate the effects of dietary nucleotides on weanling pig growth performance, nutrient digestibility, fecal score, and blood profile after being orally challenged with E. coli K88. METHODS: In Exp. 1, a total of 140 weanling pigs [8.33 ± 0.33 kg of body weight (BW), 28-d old] were used in this 42-d feeding trial. Pigs were distributed into 1 of 4 treatments, 5 pigs/pen (3 barrows and 2 gilts) and 7 pens/treatment. Treatments were a control basal diet (CON) or the CON supplemented with 150 (R150), 220 (R220), or 275 (R275) mg/kg to give the three treatment diets. In Exp. 2, 28 weanling pigs (BW = 8.40 ± 0.22 kg, 28-d old) were distributed into 1 of 4 treatments to give 1 pig/pen and 7 pens/treatment in a 42-d feeding and challenge trial. Dietary treatments were the same as in Exp. 1. On d 14, all those pigs (BW = 13.3 ± 0.15 kg, 42-d old) were orally dosed with 1.5 mL suspension containing 10(10) cfu/mL of E. coli K88. Twenty four hours after challenge, blood and excreta samples were collected from each pigs for analysis. Fecal scores were measured on d 7, 14, 21, and 28 of the study. RESULTS: In Exp. 1, overall BW, average daily gain (ADG), gain/feed (G/F) ratio, and nutrient digestibilities were lower (P < 0.05) in CON group compared with the nucleotides fed pigs. In Exp. 2, after challenge, IgA, IgM, and IGF-I were higher (P < 0.05) in the nucleotide groups compared with CON. However, the nucleotide groups had lower (P < 0.05) cortisol and TNF-α compared with CON. Fecal E. coli counts and fecal score for the nucleotide groups were lower (P < 0.05) than for CON. CONCLUSIONS: In conclusion, dietary nucleotides supplementation could improve growth performance, nutrient digestibility, immune status, microbial balance, reduce diarrhea, and provide protection against enterotoxigenic E. coli K88 infection in weanling pigs.

15.
Bioresour Technol ; 153: 131-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24355503

RESUMO

Immobilization of microorganisms for sludge anaerobic digestion was investigated in this study. The effects of filler properties on anaerobic digestion and dewaterability of waste activated sludge were assessed at mesophilic temperature in batch mode. The results showed that the duration of the methanogenic stage of reactors without filler, with only filler, and with pre-incubated filler was 39days, 19days and 13days, respectively, during which time the protein was degraded by 45.0%, 29.4% and 30.0%, and the corresponding methane yield was 193.9, 107.2 and 108.2mL/g volatile suspended solids added, respectively. On day 39, the final protein degradation efficiency of the three reactors was 45.0%, 40.9% and 42.0%, respectively. The results of normalized capillary suction time and specific resistance to filtration suggested that the reactor incorporating pre-incubated filler could improve the dewaterability of digested sludge, while the effect of the reactor incorporating only filler on sludge dewaterability was uncertain.


Assuntos
Biofilmes , Esgotos/microbiologia , Águas Residuárias/microbiologia , Purificação da Água/métodos , Anaerobiose , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Biopolímeros/análise , Reatores Biológicos/microbiologia , Filtração , Metano/análise , Oxigênio/análise , Tamanho da Partícula , Fatores de Tempo , Volatilização
16.
Waste Manag ; 34(8): 1381-90, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24820662

RESUMO

The effects of rice straw addition level on odorous compounds emissions in a pilot-scale organic fraction of municipal solid waste (OFMSW) composting plant were investigated. The cumulative odorous compounds emissions occurred in a descending order of 40.22, 28.71 and 27.83 mg/dry kg of OFMSW for piles with rice straw addition level at ratio of 1:10, 2:10 and 3:10 (mixing ratio of rice straw to OFMSW on a wet basis), respectively. The mixing ratio of rice straw to OFMSW had a statistically significant effect on the reduction of malodorous sulfur compounds emissions, which had no statistically significant effect on the reduction of VFAs, alcohols, aldehydes, ketones, aromatics and ammonia emissions during composting, respectively. The cumulative emissions of malodorous sulfur compounds from piles with the increasing rice straw addition level were 1.17, 1.08 and 0.88 mg/dry kg of OFMSW, respectively. The optimal mixing ratio of rice straw to OFMSW was 1:5. Using this addition level, the cumulative malodorous sulfur compounds emissions based on the organic matter degradation were the lowest during composting of OFMSW.


Assuntos
Odorantes , Eliminação de Resíduos/métodos , Solo , Álcoois/química , Aldeídos/química , Amônia/química , Cidades , Monitoramento Ambiental/métodos , Cetonas/química , Compostos Orgânicos , Oryza , Oxigênio/química , Consumo de Oxigênio , Enxofre/química , Temperatura , Terpenos/química , Compostos Orgânicos Voláteis/química
17.
Bioresour Technol ; 140: 131-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23685650

RESUMO

Aerobic and anaerobic digestion are popular methods for the treatment of waste activated sludge. However, the differences in degradation of sludge during aerobic and anaerobic digestion remain unclear. In this study, the sludge degradation during aerobic and anaerobic digestion was investigated at mesophilic temperature, focused on protein based on the degradation efficiency and degree of humification. The duration of aerobic and anaerobic digestion was about 90 days. The final degradation efficiency of volatile solid was 66.1 ± 1.6% and 66.4 ± 2.4% under aerobic and anaerobic conditions, respectively. The final degradation efficiency of protein was 67.5 ± 1.4% and 65.1 ± 2.6% under aerobic and anaerobic conditions, respectively. The degradation models of volatile solids were consistent with those of protein under both aerobic and anaerobic conditions. The solubility of protein under aerobic digestion was greater than that under anaerobic digestion. Moreover, the humification index of dissolved organic matter of aerobic digestion was greater than that during anaerobic digestion.


Assuntos
Proteínas de Bactérias/metabolismo , Esgotos/microbiologia , Temperatura , Eliminação de Resíduos Líquidos/métodos , Aerobiose , Anaerobiose , Biodegradação Ambiental , Reatores Biológicos/microbiologia , Carbono/análise , Substâncias Húmicas/análise , Interações Hidrofóbicas e Hidrofílicas , Nitrogênio/análise , Compostos Orgânicos/química , Espectrometria de Fluorescência , Volatilização
18.
Chin Med J (Engl) ; 126(3): 494-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23422113

RESUMO

BACKGROUND: Acute lung injury (ALI) is a common syndrome associated with high morbidity and mortality in emergency medicine. Cell apoptosis plays a key role in the pathogenesis of ALI. Hydrogen sulfide (H(2)S) plays a protective role during acute lung injury. We designed this study to examine the role of H(2)S in the lung alveolar epithelial cell apoptosis in rats with ALI. METHODS: Sixty-nine male Sprague Dawley rats were used. ALI was induced by intra-tail vein injection of oleic acid (OA). NaHS solution was injected intraperitonally 30 minutes before OA injection as the NaHS pretreatment group. Single sodium hydrosulfide pretreatment group and control group were designed. Index of quantitative assessment (IQA), wet/dry weight (W/D) ratio and the percentage of polymorphonuclear leukocyte (PMN) cells in the bronchoalveolar lavage fluid (BALF) were determined. H(2)S level in lung tissue was measured by a sensitive sulphur electrode. Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and Fas protein was measured by immunohistochemical staining. RESULTS: The level of endogenous H(2)S in lung tissue decreased with the development of ALI induced by OA injection. Apoptosis and Fas protein in alveolar epithelial cells increased in the ALI of rats but NaHS lessened apoptosis and Fas protein expression in alveolar epithelial cells of rats with ALI. CONCLUSION: Endogenous H(2)S protects rats from oleic acid-induced ALI, probably by inhibiting cell apoptosis.


Assuntos
Lesão Pulmonar Aguda/metabolismo , Sulfeto de Hidrogênio/metabolismo , Sulfetos/farmacologia , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/tratamento farmacológico , Animais , Apoptose/fisiologia , Células Epiteliais/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Masculino , Ácido Oleico/toxicidade , Ratos , Ratos Sprague-Dawley , Sulfetos/uso terapêutico
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