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1.
Water Sci Technol ; 89(4): 1047-1062, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38423616

RESUMEN

With the background of carbon neutrality, the resource and energy utilization of excess sludge (ES) have become the focus of future research. The pyrolysis of ES can produce biochar and enrich phosphorus (P). In this paper, the existing forms and recovery efficiencies of P in biochar from ES (BCES) were investigated. The results showed that the total phosphorus (TP) content of BCES at 850 °C was 65.1 mg/g, and the inorganic phosphorus (IP) content was 64.2 mg/g. The TP content of BCES was two times heavier than that of ES. The main ingredient of ES was quartz (SiO2), while the main phases of BCES were quartz (SiO2) and aluminum phosphate (AlPO4) at 650 -850 °C, and P mainly existed in the form of AlPO4. When the pyrolysis temperature was 800 and 850 °C, two new minerals appeared: Ca5(PO4)3OH and CaZn2(PO4)2·2H2O. Based on the conditions of a leaching time of 150 min, a H2SO4 concentration of 0.2 mol/L, a stirring rate of 220 rpm and a liquid-solid ratio of 50 mL/g, the leaching efficiency of P in BCES was found to be 100%. The pyrolysis temperature had no effect on leaching efficiencies of P; however, a higher pyrolysis temperature promoted metal leaching content.


Asunto(s)
Fósforo , Aguas del Alcantarillado , Cuarzo , Dióxido de Silicio , Carbón Orgánico
2.
Chemosphere ; 352: 141518, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38387664

RESUMEN

Under the background of carbon neutrality, resource and energy utilization technologies have become the focus of future research. The paper investigated the removal efficiencies and varying characteristics of substrates and microbial community structure in the simultaneous sulfide and nitrate biological removal (SSNBR) process. The results showed that the sulfide and nitrate removal loads reached 2.998 kg m-3∙d-1 and 1.011 kg m-3∙d-1 respectively when HRT was 2.4 h. The sulfide and nitrate molar ratios (S/N ratios) hardly influenced the removal efficiencies of sulfide and nitrate. However, the reaction products sulfate and nitrite concentrations in the effluent became higher as the S/N ratios decreased. Under the S/N ratio of 5:5, when the influent sulfide and nitrate concentrations were improved from 100 mg L-1 to 600 mg L-1 and from 87.5 mg L-1 to 306.25 mg L-1, respectively, the sulfide removal efficiencies were all above 99%, but the nitrate removal efficiencies reduced from 95.53% to 55.54%. Sulfide removal effect was better than nitrate. HRT had great effect on the nitrate removal efficiencies, but hardly affected the sulfide removal. When HRT was shortened from 12 h to 2.4 h, the sulfide removal efficiencies were all above 99%, while the nitrate removal efficiencies decreased from 93.14% to 77.04%. The main functional genera included Exiguobacterium, Clostridium, Bacillus, Thiobacillus and Sphingomonas, all of which had the nitrogen and sulfur removal functions.


Asunto(s)
Microbiota , Thiobacillus , Nitratos , Sulfuros , Azufre , Reactores Biológicos/microbiología , Desnitrificación , Nitrógeno
3.
Environ Sci Pollut Res Int ; 30(47): 104592-104602, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37707738

RESUMEN

In this study, a laboratory-scale partial nitrification reactor (PN reactor) was used to treat high-ammonia-nitrogen wastewater, by changing the influent NH4+-N conversion rate as the main operating strategy, to investigate the upper limit of its NH4+-N conversion rate (ACR) and explore its feasibility as an anammox pre-process. During the experiment, PN reactor was successfully activated in only 10 days. The PN reactor reached the highest ACR value of approximately 10.24 kg N/(m3 · day) when the influent ACR was 16.57 kg N/(m3 · day), and the ammonia conversion efficiency (ACE) was 61.78% at this time. The ratio of [NO2--N]Eff/[NH4+-N]Eff was approximately 1.37 which was close to the theoretical ratio of 1.32. And feasibility exploration experiment proved that it was feasible to use this PN reactor as a pre-process of anammox. The PCR-DGGE results showed that the dominant phylum and genus in the reactor during the ACR experiment were Proteobacteria and Nitrosomonas, respectively. With the increase in the ACR, the relative concentration of Nitrosomonas sp. G1 increased from 15 to 40%. This indicates that its abundance is directly correlated with the increase in the ACR. High-throughput sequencing showed that increasing the ACR of the PN reactor greatly reduced the diversity and abundance of the system microbial community structure and changed the dominant phylum and genus; however, the stability of the system was not disrupted. High-throughput sequencing experiments showed that the abundance value of nitrosation enzymes accounted for 91.62%, which was positively correlated with the expression of nitrification genes in the genus Nitrosomonas.


Asunto(s)
Amoníaco , Oxidación Anaeróbica del Amoníaco , Reactores Biológicos/microbiología , Oxidación-Reducción , Aguas Residuales , Nitrificación , Nitrógeno/metabolismo , Nitrosomonas , Aguas del Alcantarillado/microbiología , Desnitrificación
4.
J Food Sci ; 87(11): 5142-5152, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36226778

RESUMEN

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in various foods continuously concern the public. Pork and its byproducts, especially from Yorkshire pigs, are the largest meat food consumed by the general population in China. This study aims to investigate the distribution of PCDD/Fs in different tissues of Yorkshire pigs to understand their bioaccumulation. Yorkshire pigs were fed a known amount of PCDD/Fs through fly ash. PCDD/Fs were determined by isotope dilution method with a gas chromatography-high resolution mass spectrometer. The liver had the highest concentration levels (2041.33 pg/g lipid) and toxic equivalents values (69.14 pg/g lipid), followed by the spleen and lung, and the lowest ones in the brain. The liver also had the highest bioaccumulation of PCDD/Fs, and this level was considerably higher than that of other tissues. This study showed a strong accumulation capacity of the liver for polychlorinated dibenzo-p-dioxins and dibenzofurans under short-term exposure conditions, suggesting that the liver is a more sensitive tissue for monitoring PCDD/Fs in food safety risk monitoring. PRACTICAL APPLICATION: This paper may help the consumer in making food choices to minimize the exposure risk to Polychlorinated dibenzo-p-dioxins and dibenzofurans.


Asunto(s)
Dioxinas , Dibenzodioxinas Policloradas , Animales , Humanos , Porcinos , Dibenzofuranos , Dibenzofuranos Policlorados , Bioacumulación , Lípidos
5.
J Biotechnol ; 359: 176-184, 2022 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-36243184

RESUMEN

To investigate the role of the sugar transporter MAL31 on pullulan biosynthesis, the coding gene mal31 was respectively disrupted and overexpressed in the parental strain A. pullulans CCTCC M 2012259 to construct mutants of A. pullulans Δmal31 and A. pullulans Mal31. Batch pullulan production significantly decreased by 69.1 % in A. pullulans Δmal31 but increased by 15.9 % in A. pullulans Mal31, as compared to the parental strain. We performed kinetics analysis, assays of key enzymes, determination of intracellular UDPG, NADH, and ATP contents, and measurement of transcriptional levels of genes associated with pullulan biosynthesis and excretion. The results confirmed that the mal31 disruption decreased the glucose consumption rate, decreased the formation rate and titer of pullulan, but increased the intracellular UDPG supply for ß-glucan accumulation. In contrast, the mal31 overexpression increased the transcriptional levels of genes associated with pullulan biosynthesis, and accelerated the rates of glucose consumption and pullulan formation, thereby increased pullulan production. Our findings revealed that MAL31 is involved in the transport of precursors for pullulan biosynthesis. This study provides an accurate operating site for genetic modification of A. pullulans for improving pullulan production and also presents a feasible technique route for the overproduction of other polysaccharides.


Asunto(s)
Ascomicetos , beta-Glucanos , Ascomicetos/genética , Fermentación , Uridina Difosfato Glucosa , NAD , Adenosina Trifosfato , Glucosa , Azúcares
6.
J Neuroimmunol ; 337: 577074, 2019 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-31693967

RESUMEN

Patients with chronic inflammatory demyelinating polyneuropathy (CIDP) seropositive for autoantibodies against nodal and paranodal proteins display distinct clinical presentations. We herein tested for autoantibodies against neurofascin (NF) 155, NF186, contactin-associated protein 1 and contactin-1 and investigated the autoantibody-related clinical features in 29 patients with CIDP from China. Six patients with anti-NF155 IgG4 antibodies displayed younger age of onset and poor response to intravenous immunoglobulin than seronegative patients. One patient had anti-NF186 IgG antibody and no patients had anti-contactin-associated protein 1 or anti-contactin-1 antibodies. Clinical features of CIDP patients with anti-NF155 antibodies in China were similar to those reported in other countries.


Asunto(s)
Autoanticuerpos/sangre , Inmunoglobulina G/sangre , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/sangre , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/epidemiología , Adolescente , Adulto , Anciano , Animales , Autoanticuerpos/inmunología , China/epidemiología , Femenino , Células HEK293 , Humanos , Inmunoglobulina G/inmunología , Masculino , Ratones Endogámicos C57BL , Persona de Mediana Edad , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/inmunología , Adulto Joven
7.
AJR Am J Roentgenol ; 204(1): 83-91, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25539241

RESUMEN

OBJECTIVE: The purpose of this article is to compare transrectal ultrasound (TRUS) biopsy accuracies of operators with different levels of prostate MRI experience using cognitive registration versus MRI-TRUS fusion to assess the preferred method of TRUS prostate biopsy for MRI-identified lesions. SUBJECTS AND METHODS; One hundred patients from a prospective prostate MRI-TRUS fusion biopsy study were reviewed to identify all patients with clinically significant prostate adenocarcinoma (PCA) detected on MRI-targeted biopsy. Twenty-five PCA tumors were incorporated into a validated TRUS prostate biopsy simulator. Three prostate biopsy experts, each with different levels of experience in prostate MRI and MRI-TRUS fusion biopsy, performed a total of 225 simulated targeted biopsies on the MRI lesions as well as regional biopsy targets. Simulated biopsies performed using cognitive registration with 2D TRUS and 3D TRUS were compared with biopsies performed under MRI-TRUS fusion. RESULTS: Two-dimensional and 3D TRUS sampled only 48% and 45% of clinically significant PCA MRI lesions, respectively, compared with 100% with MRI-TRUS fusion. Lesion sampling accuracy did not statistically significantly vary according to operator experience or tumor volume. MRI-TRUS fusion-naïve operators showed consistent errors in targeting of the apex, midgland, and anterior targets, suggesting that there is biased error in cognitive registration. The MRI-TRUS fusion expert correctly targeted the prostate apex; however, his midgland and anterior mistargeting was similar to that of the less-experienced operators. CONCLUSION: MRI-targeted TRUS-guided prostate biopsy using cognitive registration appears to be inferior to MRI-TRUS fusion, with fewer than 50% of clinically significant PCA lesions successfully sampled. No statistically significant difference in biopsy accuracy was seen according to operator experience with prostate MRI or MRI-TRUS fusion.


Asunto(s)
Competencia Clínica/estadística & datos numéricos , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/estadística & datos numéricos , Imagen por Resonancia Magnética Intervencional/estadística & datos numéricos , Neoplasias de la Próstata/patología , Técnica de Sustracción/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis y Desempeño de Tareas
8.
Artículo en Inglés | MEDLINE | ID: mdl-24854709

RESUMEN

A simple method for the determination of six sulfonamides (SAs) in milk samples was developed. 1-Butyl-3-methylimidazolium tetrafluoroborate and trisodium citrate dihydrate were used to form aqueous two-phase system. The aqueous two phase system was applied to the extraction of the SAs and the determination of the analytes was performed by high-performance liquid chromatography. To achieve optimum extraction performance, several experimental parameters, including the type and the amount of salt, the type and amount of ionic liquid, ultrasonic time and pH of sample solution, were investigated and optimized. Under the optimal experimental conditions, good linearity was observed in the range of 8.55-1036.36ngmL(-1). The limits of detection and quantification were in the range of 2.04-2.84 and 6.73-9.37ngmL(-1), respectively. The present method was successfully applied to the determination of SAs in milk samples, and the recoveries of analytes were in the range of 72.32-108.96% with relative standard deviations ranging from 0.56 to 12.20%. The results showed that the present method was rapid, feasible and environmentally friendly.


Asunto(s)
Productos Lácteos/análisis , Leche/química , Sulfonamidas/análisis , Animales , Bovinos , Cromatografía Líquida de Alta Presión/métodos , Citratos , Concentración de Iones de Hidrógeno , Imidazoles , Líquidos Iónicos/química , Extracción Líquido-Líquido , Reproducibilidad de los Resultados , Citrato de Sodio , Sulfonamidas/aislamiento & purificación
9.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 5): o732, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23723884

RESUMEN

The chloro-phenyl group of the title compound, C18H12ClNO4, is disordered over two orientations with occupancies of 0.331 (8) and 0.669 (8). An intra-molecular hydrogen bond is formed between a hy-droxy group and the acyclic carbonyl group. In the crystal, molecules are linked into chains along [110] by O-H⋯O and C-H⋯O hydrogen bonds, forming a ladder motif.

10.
J Rheumatol ; 40(6): 850-8, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23547215

RESUMEN

OBJECTIVE: Interstitial lung disease (ILD) is a common complication of systemic sclerosis (SSc) and causes death. Once lung fibrosis occurs, disease course may become stable or decline. Little is known about risks for progression. We studied SSc-gastroesophageal (GE) involvement in relation to worsening forced vital capacity (FVC) on pulmonary function tests (PFT) to investigate whether it was related to progression. Our objective was to determine whether GE reflux and dysphagia are associated with progressive moderate/severe ILD as measured by PFT over 3 years. METHODS: The Canadian Scleroderma Research Group is a multicenter SSc database that collects data annually. Using indicators of GE involvement and annual PFT, comparisons were made between no/mild ILD, stable moderate/severe ILD, and progressive moderate/severe ILD groups based on changes of FVC. Multivariate analyses determined associations between GE factors and ILD development and progression. RESULTS: There were 1043 patients with SSc (mean age 55.7 yrs, mean disease duration 10.8 yrs); one-quarter had pulmonary fibrosis on chest radiograph that was related to FVC percentage predicted (Spearman's rho -0.39; p < 0.01). Physician indicators such as esophageal dysmotility (p = 0.009) and postesophageal dilatation (p = 0.041), and patient indicators such as difficulty swallowing (p = 0.016) and waking up choking (p = 0.026) were associated with low FVC. In comparing progressive and stable moderate/severe FVC (< 70% predicted), early satiety (p = 0.018) and a combination term of postdilatation and choking (p = 0.042) increased risk of progression of ILD. Topoisomerase I was not associated with progression over followup. CONCLUSION: Symptoms of esophageal dysmotility were associated with worsening FVC in SSc, especially if both need for esophageal dilatation and choking were present.


Asunto(s)
Reflujo Gastroesofágico/fisiopatología , Enfermedades Pulmonares Intersticiales/fisiopatología , Fibrosis Pulmonar/fisiopatología , Esclerodermia Sistémica/fisiopatología , Capacidad Vital/fisiología , Adulto , Anciano , Progresión de la Enfermedad , Femenino , Reflujo Gastroesofágico/complicaciones , Humanos , Enfermedades Pulmonares Intersticiales/etiología , Masculino , Persona de Mediana Edad , Fibrosis Pulmonar/etiología , Pruebas de Función Respiratoria , Esclerodermia Sistémica/complicaciones
11.
Dalton Trans ; 40(38): 9789-94, 2011 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-21879078

RESUMEN

A novel strategy was utilized to develop a stable probe based on thiolated poly(ethylene glycol) (SH-PEG) and polyacrylic acid (PAA) functionalized gold nanorods (GNRs), following the attachment of an anti-cancer drug, doxorubicin (DOX), to obtain PAA-PEG-GNRs@DOX assemblies. Importantly, the obtained probe as a novel drug-delivery and fluorescent imaging agent for simultaneous imaging of and drug delivery to prostate cancer cells has also been demonstrated. In addition to designing PAA-PEG-GNRs that passively target tumor cells for cancer-fighting drug therapy, GNRs are also regarded as hyperthermia agents for photokilling cancer cells, so that the tumor would be attacked on two fronts simultaneously.


Asunto(s)
Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos , Imagen por Resonancia Magnética , Neoplasias/diagnóstico , Neoplasias/tratamiento farmacológico , Resinas Acrílicas/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Doxorrubicina/química , Ensayos de Selección de Medicamentos Antitumorales , Oro/química , Humanos , Nanotubos/química , Polietilenglicoles/química , Relación Estructura-Actividad , Células Tumorales Cultivadas
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