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1.
Microbiologyopen ; 9(3): e983, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31902141

RESUMO

Soil microorganisms are considered to be important indicators of soil fertility and soil quality. Most previous studies have focused solely on surface soil, but there were numerous active cells in deeper soil layers. However, studies regarding microbial communities in deeper soil layers were not comprehensive and sufficient. In this study, phylogenetic molecular ecological networks (pMENs) based on the 16S rRNA Miseq sequencing technique were applied to study the response of soil microbial communities to depth gradients and the changes of key genera along 3 meter depth gradients (0-0.2 m, 0.2-0.4 m 0.4-0.6 m, 0.6-0.8 m, 0.8-1.0 m, 1.0-1.3 m, 1.3-1.6 m, 1.6-2.0 m, 2.0-2.5 m, and 2.5-3.0 m). The results showed that the modularity of microbial communities was consistently high in all soil layers and each layer was similar, which indicated that microbial communities were more resistant to depth changes. The pMENs further demonstrated that microbial community interactions were stable as the depth increased and they cooperated well to adapt to changes in different soil gradients. This was evidenced by similar positive links, average degree, and average clustering coefficient. In addition, key genera were obtained by analyzing module hubs in the pMENs. There may be at least one dominant genus in each layer that adapted to and resisted changes in the soil environment. It seems microbial communities demonstrate a stable and strong adaptability to depth gradients in farmland soils.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31652639

RESUMO

This study concerned the sediment issue of the Yellow River basin. The responses of hydrological and sedimental processes to future climate change in two upland watersheds with different dominant landscapes were estimated. Four Representative Concentration Pathway (RCP) scenarios with different radiative forcing levels were considered. The outputs of eleven Global Climate Models (GCMs) were used to represent the future climate status of the 2050s and 2070s, and an ensemble means was achieved to avoid uncertainty. The Long Ashton Research Station Weather Generator (LARS-WG) was employed to downscale the outputs of GCMs for future site-scale daily weather data estimations. The Generalized Watershed Loading Functions (GWLF) model was employed to model the streamflow and sediment yields under various scenarios and periods. The results showed that there would be generally hotter and wetter weather conditions in the future. Increased erosion and sediment yields could be found in the study area, with lesser increments in sediment in woodland than in cultivated field. The peak of sediment would appear in the 2050s, and integrated measures for sediment control should be implemented to reduce erosion and block delivery. The multi-model approach proposed in this study had reliable performance and could be applied in other similar areas with modest data conditions.


Assuntos
Mudança Climática , Sedimentos Geológicos , Abastecimento de Água , China , Previsões , Hidrologia , Rios , Tempo (Meteorologia)
3.
ACS Appl Mater Interfaces ; 11(45): 42375-42384, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31647866

RESUMO

A methodology was developed to design superior sorbents of oxoanions. To integrate the high efficiency of chemisorption, selectivity, and recyclability into one sorbent, understanding the nature of oxoanions-sorbent interactions and the structural evolution of the sorbents is essential. Three cationic Ag(I) coordination polymers (CPs) are synthesized for dichromate (Cr2O72-) removal, and three distinct oxoanion-exchange mechanisms are identified, namely, the replacement, breath, and reconstruction processes, depending on the degree of framework distortion induced by the dichromate-CP interactions. The single crystal to single crystal transformation during the oxoanion exchange has been investigated by using single-crystal X-ray diffraction and energy-dispersive X-ray microanalysis. The replacement process, due to a weak chemisorption, shows excellent recyclability at the cost of reduction of efficiency and selectivity of adsorption. The reconstruction process may achieve a high efficiency and selectivity, but it loses recyclability. Due to the formation of a Ag-O(dichromate) bond and the breathing effect of the framework, the sorbent with the breath mechanism shows both superior efficiency and high recyclability in dichromate removal. The study of perrhenate (ReO4-) removal using the same CPs demonstrates that one CP performing the reconstruction process during dichromate removal turns to the breath process in removal of perrhenate anions. These results of mechanism-property correlation provide an insight into improvement of the methodology to fabricate a superior CP sorbent for oxoanion removal.

4.
Sci Total Environ ; 685: 867-885, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247435

RESUMO

Core samples may be used as valuable geochronometers for storing historical pollution footprints of organic pollutants. A number of studies have used core samples to evaluate temporal depositions, loading inventories, and effectiveness of environmental mitigation measures. However, in order to get a reliable estimation, certain prerequisites must be satisfied to rule out various confounding factors such as biomixing and melting. This review aims to understand when core samples can or cannot be used as natural archives for organic pollutants. First, we systematically review existing studies of organic pollutants in soil, sediment and ice cores and possible factors that may influence post-depositional fate of chemicals. Then, building on field evidence, model simulation and laboratory leaching tests findings, we discuss issues of post-depositional downward movement in detail. To assist future core sample studies, we summarize lessons learned on study design in the context of sampling design, data analysis, and data reporting. In particular, the combination of a careful study design and appropriate numerical model(s) will help to elevate core samples as a more reliable tool for retrospective understanding of chemical pollution. This review is an initial step toward a better and more accurate use of core samples, and further interdisciplinary cooperation is needed to develop standardized protocols, guidelines and tools.

5.
Medicine (Baltimore) ; 98(25): e15915, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31232924

RESUMO

RATIONALE: Osteochondral flap fractures of the elbow are rare in children. To the best of our knowledge, only 12 cases are reported in the literature. Only 1 case was accompanied with lateral condyle fracture classified as Milch I, which was nondisplaced. The mechanism of these injuries is not explained in detail, and the treatment methods are not discussed. Here, we present 3 cases of osteochondral flap fracture of the ulnar coronoid process with accompanying obvious displacement of the lateral condyle fracture. PATIENT CONCERNS: All patients fell into one of their outstretched arms, which caused elbow pain and functional limitation. DIAGNOSIS: All 3 patients were diagnosed with lateral condyle fracture of the humerus and osteochondral flap fracture of the ulnar coronoid process. INTERVENTIONS: All patients underwent open reduction and internal fixation. OUTCOMES: At 3 months after the operation, they regained full range of motion of the limb and had no elbow instability. LESSONS: Osteochondral flap fracture should be considered when there is a bone mass in the elbow space with accompanying displacement of the humeral lateral condyle fracture.


Assuntos
Articulação do Cotovelo/lesões , Fraturas do Úmero/diagnóstico , Fraturas Intra-Articulares/diagnóstico , Luxações Articulares/diagnóstico , Ulna/lesões , Acidentes por Quedas , Pré-Escolar , Diagnóstico Diferencial , Feminino , Fixação Interna de Fraturas , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/cirurgia , Fraturas Intra-Articulares/diagnóstico por imagem , Fraturas Intra-Articulares/cirurgia , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/cirurgia , Imagem por Ressonância Magnética , Masculino , Amplitude de Movimento Articular , Tomografia Computadorizada por Raios X
6.
Medicine (Baltimore) ; 98(25): e16152, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31232970

RESUMO

To compare the efficacy of curettage and bone grafting combined with elastic intramedullary nailing (EIN) vs curettage and bone grafting in the treatment of long bone cysts in children and to clarify the necessity of using EIN in the treatment of bone cysts.Sixty-two patients were involved in this study from Jan. 2009 to Sept. 2017 (43 males, 19 females; 27 humeri, 35 femurs); the patients were assigned to an EIN group, comprising 30 patients who underwent curettage and bone grafting combined with EIN, or to a non-elastic intramedullary nailing (NEIN) group, comprising 32 patients who underwent curettage and bone grafting alone. The prognosis of the 2 groups was assessed with reference to the standard of Capanna.No statistically significant differences in sex, age, location, activity, pathological fracture, cyst volume, operative time and intraoperative blood loss were found between the 2 groups (P > .05). The effective rate was 90.0% in the EIN group and 68.8% in the NEIN group, and the difference was statistically significant (P < .05).Compared to simple curettage and bone grafting, curettage and bone grafting combined with EIN treatment can significantly improve the prognosis of children with bone cysts. It is recommended that EIN be added to bone cyst curettage and bone grafting.


Assuntos
Cistos Ósseos/cirurgia , Transplante Ósseo/normas , Fixação Intramedular de Fraturas/normas , Pinos Ortopédicos/normas , Pinos Ortopédicos/estatística & dados numéricos , Transplante Ósseo/métodos , Transplante Ósseo/estatística & dados numéricos , Criança , Curetagem/métodos , Feminino , Fêmur/anormalidades , Fêmur/cirurgia , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/estatística & dados numéricos , Humanos , Úmero/anormalidades , Úmero/cirurgia , Masculino , Radiografia/métodos , Estudos Retrospectivos , Resultado do Tratamento
7.
Environ Sci Pollut Res Int ; 26(11): 10695-10707, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30778933

RESUMO

The standardized precipitation index (SPI) and the standardized precipitation evapotranspiration index (SPEI) based on two different methods were calculated using monthly meteorological data from the Yangtze River Basin. According to the completeness and length of dataset, the monthly data of 35 meteorological stations from 1959 to 2017 were applied in this study. The results revealed that the SPEI calculated by the Penman-Monteith (PM) method performed better than the SPI and the SPEI based on the Thornthwaite (TH) method. Since SPEI_PM considered more meteorological factors and detailed physical processes, it obtained the most reasonable and accurate results of drought trends. Using the variations of SPEI_PM to analyze the decadal changes of drought characteristics in the basin, it could be found that 1980-1989 and 1990-1999 were the most humid periods in the basin, while the drought events became more frequent and severe in the recent decade. The spatial distributions of drought trend, duration and frequency indicated that the stations located in the midstream of the river were most prone to drought events, followed by the upper reaches. Our results provided more information for the regions where severe droughts occurred frequently and last longer, and more attention should be paid to these regions in future catchment management.


Assuntos
Meteorologia/métodos , Rios/química , Clima , Secas , Meteorologia/normas , Chuva/química , Padrões de Referência
8.
Environ Sci Pollut Res Int ; 26(11): 11062-11073, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30788701

RESUMO

In this study, reduced graphene oxide (RGO) was synthesized by L-ascorbic acid reduction, which was a relatively mild and environmental friendly reduction method, and the adsorption of organic contaminants was compared to graphene oxide (GO) to probe the potential adsorption mechanisms. The morphology properties of GO and RGO were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared transmission (FTIR), Raman spectrometer, transmission electron microscope (TEM), and scanning electron microscopy (SEM). The adsorption affinities of GO and RGO for phenanthrene and 1-naphthol were studied in batch experiments. The effects of pH and surfactants were also assessed. The results demonstrated that RGO reduced by L-ascorbic acid show significantly greater adsorption affinity for both phenanthrene and 1-naphthol than GO, and even greater than most of RGOs that reduced by the strong reductive reagents. This was mainly attributed to the hydrophobic interaction, π-π interaction, and H-bonding between graphene sheets and organic contaminants. Both GO and RGO showed stronger adsorption to phenanthrene than to 1-naphthol. The adsorption of 1-naphthol increased with decreasing pH and reached a maximum around pH = 7.34. The surfactants, sodium dodecyl benzene sulfaonate (SDBS) and cetyltrimethyl ammonium bromide (CTAB), had negligible influence on adsorption to GO. Note that CTAB significantly inhibited the adsorption of phenanthrene/1-naphthol on RGO, which could be attributed to the pore blockage effect. In addition, RGO could be regenerated and reused with high recyclability over five cycles. The present study suggests that RGO obtained via L-ascorbic acid reduction can be deemed as a promising material for organic contaminated wastewater treatment.


Assuntos
Ácido Ascórbico/química , Grafite/química , Naftóis/química , Fenantrenos/química , Tensoativos/química , Poluentes da Água/química , Adsorção , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Óxidos/química , Espectroscopia Fotoeletrônica , Análise Espectral Raman , Purificação da Água
9.
Inorg Chem ; 58(1): 18-21, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30556396

RESUMO

Four-fold interpenetrating framework 1a can be constructed driven by temperature-controlled SC-SC transformation from 2-fold interpenetrating network 1. Luminescent properties indicated that 1a can be viewed as a luminescent sensor of high-explosives.

10.
Artigo em Inglês | MEDLINE | ID: mdl-30558148

RESUMO

We investigated the concentrations of 10 heavy metals in Potamogeton malaianus, Nymphoides peltata, Eichhornia crassipes, and Hydrilla verticillata to evaluate their potential to bioaccumulate heavy metals and related influencing factors in Taihu Lake. Enrichment factor (EF) values of Cu, Cr, Mn, Ni, Zn, Co, Pb, and V were above 2.0, indicating moderate to significant contamination in sediment. Most of Ti, V, Cr, Mn, and Ni in P. malaianus, E. crassipes, and H. verticillata and V in N. peltata were within excess/toxic level in plants, but higher than normal level. Even though no aquatic plants in this study were identified as a hyperaccumulator, relatively higher concentrations in aquatic plants were found in Taihu Lake than have been found in other previous studies. Heavy metal in submerged plants, especially in their stems, seemed to be more closely related to metals in water and sediment than those in floating-leaf plants. Ratios of metals in stem versus leaves in all plants ranged from 0.2 to 25.8, indicating various accumulation capabilities of plant organs. These findings contribute to the application of submerged aquatic plants to heavy metal removal from moderately contaminated lakes.


Assuntos
Monitoramento Ambiental , Lagos/química , Metais Pesados/análise , Metais Pesados/metabolismo , Plantas/metabolismo , Rios/química , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , China , Sedimentos Geológicos/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Caules de Planta/química , Caules de Planta/metabolismo , Plantas/química
11.
Ther Clin Risk Manag ; 14: 1789-1797, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30310287

RESUMO

The concurrent use of trastuzumab and anthracycline-based neoadjuvant chemotherapy (NAC) has been proposed to improve the pathologic complete response (pCR) rate, although there are conflicting views about its efficacy and safety. The purpose of this study was to evaluate the efficacy and cardiac safety of the concurrent use of trastuzumab and anthracycline-based NAC for human epidermal growth factor receptor 2 (HER2)-positive locally advanced breast cancer. We systematically searched PubMed, Embase, and Cochrane databases from inception until July 1, 2017, for relevant articles. A total of 13 studies were included in the meta-analysis. The results showed that the pCR rate was significantly higher in the concurrent use of trastuzumab and anthracycline group (45%) than that in the nonconcurrent use group (32%) (OR: 2.36, 95% CI: 1.69-3.30, P<0.0001). Besides, the pooled absolute rate of breast conservation surgery (BCS) was 48% (95% CI: 0.35-0.61) and 38% (95% CI: 0.14-0.62) in the experimental and control groups, respectively (OR: 1.10, 95% CI: 0.64-1.90, P=0.73). No significant differences were found in the left ventricular ejection fraction (LVEF), which decreased by >10% (OR: 1.26, 95% CI: 0.55-2.88, P=0.59), and in terms of cardiac failure (OR: 2.17, 95% CI: 0.24-19.84, P=0.49), when comparing the concurrent use of trastuzumab and anthracyclines with their nonconcurrent use. In conclusion, the concurrent use of trastuzumab and anthracycline-based NAC for certain HER2-positive locally advanced breast cancers significantly improves the pCR rates without obvious increases in the cardiotoxicity.

12.
J Cancer ; 9(17): 3168-3176, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30210640

RESUMO

Objectives: To investigate the effect of the concurrent use of trastuzumab and anthracycline-based neoadjuvant chemotherapy (NAC) for HER2-positive breast cancer in terms of pCR and cardiotoxicity. Methods: We systematically searched Pubmed, Embase, Cochrane and SinoMed databases from inception until 1 July 2017 for relevant articles of randomized controlled studies. After identified all relevant studies that reported the concurrent use of trastuzumab and anthracycline-based NAC for HER2-positive locally advanced breast cancer, five eligible randomized studies were extracted relevant data and assessed for design and quality, and the meta-analysis was conducted to evaluate the risk ratio (RR) of pCR and other interesting outcomes, such as left ventricular ejection fraction (LVEF) decrease more than 10%, responses, recurrence free survival (RFS) and overall survival (OS). Results: A total of five randomized controlled studies were included in the meta-analysis, including 232 HER2-positive locally advanced breast cancer patients received the concurrent use of trastuzumab and anthracycline-based NAC. The results showed that the pCR rate was significantly higher in the group received the concurrent use of trastuzumab and anthracycline-based NAC (48%) than that in the non-concurrent use of trastuzumab and anthracycline-based NAC group (26%) (RR: 1.76, 95%CI: 1.37-2.26, p<0.0001). Besides, higher rate of RFS (RR: 1.14, 95%CI: 1.03-1.26, p=0.009) was observed in the concurrent use of trastuzumab and anthracycline-based NAC group. No significant differences in LVEF decreased more than 10% (p=0.50) between both groups. Conclusions: Our meta-analysis of randomized controlled studies showed that pCR rates are significantly higher in the concurrent use of trastuzumab and anthracycline-based NAC compared with the non-concurrent use of trastuzumab and anthracycline-based NAC for certain HER2-positive breast cancer, meanwhile without significant increase of the cardiotoxicity.

13.
Sci Total Environ ; 624: 1131-1139, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29929225

RESUMO

Long-term nitrogen (N) fertilization affects soil aggregation and localizations of soil organic carbon (SOC), N and microbial parameters within aggregates. The mechanisms of these N effects are poorly understood. We studied these processes in a loamy soil from a 23-year repeated N addition field experiment under a rice-barley rotation. Nitrogen fertilization increased plant productivity and the portion of large macroaggregates (>2mm). However, SOC contents in macro- and micro-aggregates remained constant despite an N-induced increase of 27% in root C input into soil. Therefore, N fertilization accelerated SOC turnover. Nitrogen addition increased total N (TN) content in bulk soil and two macroaggregates (>2, and 1-2mm), but not in microaggregates (<0.25mm). Also, N fertilization increased the phospholipid fatty acids (PLFAs) contents of fungi in the large macroaggregates, but not in the microaggregates. In contrast, the effect of N addition on contents of bacterial and total microbial PLFAs was not apparent. Nitrogen fertilization increased N-acetyl-ß-D-glucosaminidase (NAG) activities in the two larger macroaggregate size classes (>2, and 1-2mm), but not in the aggregates (<1mm). In both control and N fertilization, the large macroaggregates localized more TN, microbial PLFAs, and NAG activities than the microaggregates. In conclusion, long-term N fertilization not only directly promotes soil N resource but also indirectly improves soil structure by forming large macroaggregates, accelerates SOC turnover, and shiftes localization of microorganisms to the macroaggregates.

14.
Environ Sci Pollut Res Int ; 25(20): 19488-19498, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29730758

RESUMO

As a representative index of the algal bloom, the concentration of chlorophyll-a (Chl-a) is a key parameter of concern for environmental managers. The relationships between environmental variables and Chl-a are complex and difficult to establish. Two machine learning methods, including support vector machine for regression (SVR) and random forest (RF), were used in this study to predict Chl-a concentration based on multiple variables. To improve the model accuracy and reduce the input number, two feature selection methods, including minimum redundancy and maximum relevance method (mRMR) and RF, were integrated with regression models. The results showed that the RF model had a higher predictive ability than the SVR model. Furthermore, the less computational time cost and unnecessary prior data transformation also indicated a better applicability of the RF model. The comparison between ensemble models of mRMR-RF and RF-RF showed that the RF-RF yielded a better performance with fewer variables. Seven variables selected from the candidate predictors could interpret most information, and their potential implications to Chl-a were discussed based on the level of importance. Overall, the RF-RF ensemble model can be considered as a useful approach to determine the significant stressors and achieve satisfactory prediction of Chl-a concentration.


Assuntos
Clorofila A/análise , Lagos/química , Modelos Teóricos , Qualidade da Água/normas , Algoritmos , China , Monitoramento Ambiental , Aprendizado de Máquina , Valor Preditivo dos Testes , Análise de Regressão , Máquina de Vetores de Suporte
15.
Chem Commun (Camb) ; 53(66): 9206-9209, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28722072

RESUMO

The single-crystal to single-crystal (SC-SC) transformation from a 1D coordination chain to a 3D coordination network, which is triggered by both solvent and anion exchanges, has been revealed to suffer from a tandem mechanism as proved by isolation of the intermediate state. The resulting porous crystalline material shows a high efficiency for the capture of dichromates (207 mg g-1) via the SC-SC anion-exchange.

16.
Electrophoresis ; 38(19): 2521-2529, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28719053

RESUMO

In this work, a CE method was developed to separate five anthraquinones: aloe-emodin, rhein, emodin, chrysophanol, and physcion. The CE method used a nano-sized metal organic framework MIL-101 (nMIL-101) as pseudostationary phase (PSP) and sorbent for dispersed particle extraction (DPE). The nMIL-101 was synthesized by microwave technique and was characterized by UV-vis, TEM, Zeta potential, X-ray diffraction spectrometry and micropore physisorption. In this method, anthraquinones were adsorbed by nMIL-101 of a fast kinetics within 10 min and then separated by CE. The CE conditions were optimized considering time, pH, buffer ionic strength, and nanoparticles concentration. The optimal CE condition is using 20 mM sodium borate buffer (pH 9.1) containing 15% methanol (v/v) and 400 mg/L nMIL-101 as additives within 8 min. The LODs varied from 24 to 57 µg/L, which were lower than those previously reported. Our method has been successfully applied to determine trace anthraquinones in environmental water samples.


Assuntos
Antraquinonas/isolamento & purificação , Complexos de Coordenação/síntese química , Eletroforese Capilar/métodos , Estruturas Metalorgânicas/química , Micro-Ondas , Nanopartículas/química , Poluentes Químicos da Água/isolamento & purificação , Tampões (Química) , Limite de Detecção
17.
Chemistry ; 23(51): 12593-12603, 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28657197

RESUMO

The nickel-catalyzed intermolecular cycloadditions of benzocyclobutenones with 1,3-dienes developed by Martin and co-workers are featured with the exclusive proximal C-C bond cleavage and a high chemoselectivity of the [4+4] over the [4+2] cycloaddition. In this report, the detailed reaction mechanism and the origins of the selectivities were investigated by means of density functional theory calculations. The results show that the reaction is initiated by a C-C oxidative addition of the benzocyclobutenone to form the five-membered nickelacycles. A subsequent exo 1,4-insertion/C-C reductive elimination and an endo 1,4-insertion/C-C reductive elimination lead to the [4+4] and [4+2] cycloaddition products, respectively. The 1,4-insertion of the 1,3-diene into the Ni-C bond was calculated to be the rate- and selectivity-determining step of the reaction. The calculations reproduced quite well the experimentally observed exclusive proximal C-C bond cleavage and the high chemoselectivity of the [4+4] over the [4+2] cycloaddition. In particular, it was found that the steric repulsion between the phosphine ligand and the α-substituent of the benzocyclobutenone has a dramatic impact on the 1,4-insertion, which enables the experimentally observed selectivities.

18.
Huan Jing Ke Xue ; 38(11): 4623-4631, 2017 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965406

RESUMO

Arsenic is one of the most toxic substances yet discovered and arsenic contamination of water has become a global environmental problem in need of a solution. This study has identified the capacity of sodium persulfate (PS), activated by zero-valent iron (ZVI) to remove As(Ⅴ) from waste-water is much greater than the capacity of PS alone due to the production of sulfate radicals in the process. Five parameter types including PS and ZVI dosage, reaction temperature, initial pH value, and initial As(Ⅴ) concentration are discussed in detail. These parameters affect the removal rate dynamics as an influencing factor of the As(Ⅴ) concentration. The material structure before and after the reaction was characterized by X-ray photoelectron spectroscopy analysis (XPS) and scanning electron microscopy (SEM). It was demonstrated that under this solution of 20-100 mg·L-1 of As(Ⅴ), the removal rate of As(Ⅴ) is more than 98% and a pseudo-second order kinetic model can be used to describe the reaction. The removal mechanism of ZVI/PS to As(Ⅴ) was explored by comparing the results of X-ray photo-electron spectroscopy of samples taken before and after reaction with ZVI/PS. PS can accelerate the corrosion of ZVI and then promote the adsorption of As(Ⅴ), moreover, it can also form precipitates and coprecipitates with iron oxide/hydroxide to achieve an enhanced removal of As(Ⅴ).

19.
Chem Commun (Camb) ; 53(3): 636-639, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-27990550

RESUMO

The first K/Cd heterodimetallic complex {[Cd1.5(TTPE)1.5Cl3K(H2O)3]·3H2O}n (1b) based on triazole has been generated from {[Cd(TTPE)(HCOO)](NO3)·3DMAC·H2O}n (1) during the ion- and solvent-exchange experiment in an irreversible SC-SC transformation. Based on its luminescence properties, we have, for the first time, demonstrated that 1b is a heterodimetallic sensor for detection of high-explosives and cyano molecules.


Assuntos
Cádmio/química , Substâncias Explosivas/análise , Substâncias Luminescentes/química , Nitrilos/análise , Compostos Organometálicos/química , Potássio/química , Triazóis/química , Substâncias Explosivas/química , Modelos Moleculares , Conformação Molecular , Nitrilos/química , Triazinas/análise , Triazinas/química
20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 24(6): 1801-1806, 2016 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-28024497

RESUMO

OBJECTIVE: To study the effect of G protein-coupled receptor kinase 6(GRK6) on proliferation and apoptosis of multiple myeloma(MM) cells and its mechanisms. METHODS: The samples were collected from MM patients and healthy people for study in vivo. The plasma cells isolated from multiple myeloma patients, as well as U266 and NCI H929 myeloma cell lines were used for study in vitro. Western blot and quantitative real-time PCR were used to evaluate the protein and mRNA of expression of GRK6 in multiple myeloma, cell proliferation and apoptosis were tested by BrdU and Annexin V-FITC/PI assays. RESULTS: The protein and mRNA expression of GRK6 in multiple myeloma was higher than those in control group, and the expression level of GRK6 in stage I of MM was higher than that in control group, while the expression level of GRK6 in stage II was higher than that in stage I, but lower than that in stage III (P<0.05). U266 and MM cells showed high-sensitivity to CX-4945, except NCI H929. GRK6 expression level in U266, NCI H929 and MM cells treated with siRNA and CX-4945, significantly decreased as compared with those cells treated by CX-4945 alone. Cell proliferations of U266, NCI H92 and MM groups treated with CX-4945 were (58.25±18.24)%, (64.32±20.03)% and (45.42±25.01)% respectively, moreover, their apoptotic rates were (62.82±53.21)%, (43.25±47.05)% and (85.67±40.32)% respectively. CONCLUSION: The expression level of GRK6 in multiple myeloma increases, and GRK6 inhibitor CX-4945 inhibits proliferation and promotes apoptosis of myeloma cells; GRK6 regulates Rac1 and involves in the proliferation and apoptosis pathway of multiple myeloma cells.


Assuntos
Apoptose , Mieloma Múltiplo , Linhagem Celular Tumoral , Proliferação de Células , Quinases de Receptores Acoplados a Proteína G , Humanos , RNA Mensageiro , RNA Interferente Pequeno
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