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1.
Artigo em Inglês | MEDLINE | ID: mdl-31999094

RESUMO

Perovskite solar cells (PSCs) are susceptible to intrinsic structural instability associated with the presence of inorganic halide anions and organic cation vacancies, thus leading to the deterioration or even premature failure of devices. Herein, we develop an efficient strategy using super-halogen BH4- substitution to simultaneously immobilize methylammonium and substitute iodide vacancy for high-performance PSCs based on the dihydrogen bonding interactions. The introduced super-halogen BH4- groups not only significantly reduce the vacancy density but also effectively inhibit the decomposition of the CH3NH3+ group by forming perovskite CH3NH3PbI3-x(BH4-)x. The power conversion efficiency (PCE) of the assembled mesoporous devices is remarkably promoted from 18.43 to 21.10%, accompanied by significant increase of both Jsc and Voc without obvious hysteresis. The superior PSCs can retain 90 and 80% of their initial PCE even after being stored for 1200 h under environmental conditions (50 ± 10% RH) and 240 h at 85 °C in the dark, respectively. Moreover, it delivers excellent optical stability under ultraviolet illumination. This work provides an avenue to improve both the long-term stability and photovoltaic performance of PSCs.

2.
J Sep Sci ; 43(2): 406-417, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31633862

RESUMO

Zhi-Zi-Hou-Po Decoction, consisting of Gardenia jasminoides Ellis, Magnolia officinalis Rehd. et Wils., and Citrus aurantium L, is a classical Traditional Chinese Medicine formula for the treatment of depression. In order to make good and rational use of this formula in the future, a sensitive, selective, and reliable ultra high performance liquid chromatography with tandem mass spectrometry method was developed for simultaneous determination of two iridoid glycosides (geniposide and genipin gentiobioside), two lignans (honokiol and magnolol), four flavonoid glycosides (isonaringin, naringin, hesperidin, and neohesperidin), the major bioactive constituents of Zhi-Zi-Hou-Po Decoction, in rat plasma using paeoniflorin as internal standard. Plasma samples were pretreated by a simple protein precipitation with acetonitrile. Chromatographic separation was performed on a shim-pack XR-ODS C18 column (75 × 3.0 mm, 2.2 µm) using gradient elution with mobile phase consisting of 0.1% formic acid aqueous solution and acetonitrile at a flow rate of 0.5 mL/min. Mass spectrometric detection was conducted on a 3200 QTRAP mass spectrometry equipped with electrospray ionization source in negative ionization mode. Quantification was performed using multiple reactions monitoring mode. Calibration curves exhibited good linearity (r > 0.9947) over a wide concentration range for all analytes, and the lower limits of quantification were 10, 5, 1, 5, 1, 5, 1, and 5 ng/mL for geniposide, genipin gentiobioside, honokiol, magnolol, isonaringin, naringin, hesperidin, and neohesperidin, respectively. The intraday and interday precisions at three quality control levels were less than 12.3% and the accuracies ranged from -11.2 to 10.7%. Extraction recovery, matrix effect, and stability were satisfactory in rat plasma. The validated method was successfully applied to a pharmacokinetic study of the eight analytes after oral administration of Zhi-Zi-Hou-Po decoction to rats.

3.
Asian J Surg ; 43(1): 213-219, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30879906

RESUMO

OBJECTIVE: The aim of our study was to assess how much renal malperfusion increases the risk of early and late mortality in patients with acute type A aortic dissection (ATAAD) undergoing surgical repair. METHODS: This study included 218 patients with ATAAD undergoing surgical repair using the total arch replacement and frozen elephant trunk technique. Mean age was 47.8 ± 10.7 years and 170 were male (78.0%). Based on clinical symptoms and computed tomographic angiography (CTA) findings, 48 patients were diagnosed with preoperative renal malperfusion (22.0%). Clinical data were compared between two groups. The impact of renal malperfusion on operative and late mortality were evaluated with Cox regression. RESULTS: Patients with renal malperfusion experienced significantly higher incidences of persistent postoperative acute kidney injury (AKI; 10/48, 20.8% vs 7/170, 4.1%; p < 0.001) and transient AKI (10/48, 20.8% vs 8/170, 4.7%; p = 0.001) as well as operative mortality (22.9%, 11/48 vs 8.3%, 14/170; p = 0.023). Five-year survival was significantly lower in the renal malperfusion group (72.9% vs 87.0%, p = 0.003). Renal malperfusion was the risk factor for operative mortality (hazard ratio, HR, 2.74; 95% CI, 1.07-6.99; p = 0.035) and overall mortality (HR, 2.64; 95% CI, 1.23-5.67; p = 0.013) but did not predict late death (HR, 2.46; 95% CI, 0.65-9.35; p = 0.187). CONCLUSION: Renal malperfusion increases the risk of operative mortality by 3 times but did not affect late death in patients undergoing acute type A dissection repair.

4.
ChemSusChem ; 13(1): 252-259, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31475779

RESUMO

Two-dimensional perovskite solar cells (PSCs) with high moisture resistance are a key topic in the photovoltaic field. However, their lower power conversion efficiencies (PCEs) in comparison to 3 D PSCs is still an urgent problem to be solved. It is vital to understand the impact of constituent ratios and ammonium salt sizes on the photovoltaic performance and humidity stability. Based on the formula of (RNH3 )2 (MA)n-1 Pbn I3n+1 (n=1, 3, 5, 7, 9, and 11), a series of 2 D perovskites is prepared by introducing varisized ammonium salts of ethylammonium iodide (EAI), propylammonium iodide (PAI), and butylammonium iodide (BAI). The effects of the constituent ratios and varisized ammonium salts on the properties of the 2 D perovskites were studied. 2 D perovskite devices based on larger n and smaller ammonium salt size are found to exhibit better performances. However, the moisture resistance of the 2 D perovskite devices is higher when n is smaller and the ammonium salt size is larger. Therefore, the EA2 MA10 Pb11 I34 (n=11) 2 D perovskite device displays the best photovoltaic performance, with the highest PCE of 16.93 %, whereas BA2 MA2 Pb3 I10 (n=3) 2 D perovskite, with the largest contact angle of 79.8°, can retain over 85 % of the initial PCE after 1440 h aging at 50 % relative humidity. This work indicates the PCE and stability of 2 D perovskites can be conveniently and effectively adjusted by controlling the 2 D constituent ratios and ammonium salt sizes, so as to obtain efficient 2 D PSCs with high stability.

5.
Sci Total Environ ; : 135581, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31812392

RESUMO

Plant litter plays an important role in affecting the water quality of wetland ecosystems. However, it is unknown whether litter decomposability and species traits might predict water quality changes during litter submergence. Here, we conducted a greenhouse experiment to examine the effects of four submerged plant species, together with two water sources (sampled from tourism and protected areas), and oxygen injection treatments on the changes of eight water quality parameters during litter submergence. Our results showed that litter submergence significantly affected water quality changes, and the observed effects changed through time and differed between two water sources, between oxygen injection and the control treatments, and among different litter species. Moreover, water electric conductivity (EC), total dissolved solids (TDS), water total nitrogen (TN), ammonium and nitrite nitrogen increased with increasing initial litter total carbon (TC), TN and total phosphorus (TP), but water dissolved oxygen (DO) decreased with increasing litter TC, TN and TP. Moreover, water EC, TDS and TN increased with the final mass losses after 10-week submergence. These results indicated that species traits (including decomposability) might be good predictors for the water quality changes during litter submergence, and such a trait-based approach might be a promising tool to link plant species diversity via plant functional traits to water quality or other wetland ecosystem services.

6.
ChemSusChem ; 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31849185

RESUMO

Formamidinium lead iodide-based (FAPbI3 ) perovskite is widely used in the field of photovoltaics, owing to its suitable bandgap (ca. 1.45 eV) and better thermal stability. FAPbI3 has two polymorphs (black α-FAPbI3 and yellow δ-FAPbI3 ) at ambient temperature. The yellow δ-FAPbI3 , which has no photoactivity, has a chain-like structure that likely hinders electron transport and reduces photovoltaic performance. However, pure-phase black α-FAPbI3 without any yellow phase is difficult to obtain and the underlying mechanism of the phase transition is rarely investigated. In this study, a facile bi-additive method (BA method) has been developed to completely eliminate the yellow δ-FAPbI3 phase by inducing a phase transition from δ-FAPbI3 to α-FAPbI3 . HI and Pb(SCN)2 were employed as dual additives. Based on the investigation of the annealing time and temperature, we determined that the BA method can induce the phase transition and enhance the stability of α-FAPbI3 . Owing to the enhanced crystallization as well as uniform morphology of the BA film, the perovskite solar cells (PSCs) exhibited an increased power conversion efficiency (PCE). Furthermore, the optimal devices displayed excellent stability and maintained over 80 % of initial PCE after aging for 400 h in air. This work provides a new insight into the fabrication of high-quality pure α-FAPbI3 perovskite films and makes high efficiency photovoltaic devices a reality.

7.
ACS Appl Mater Interfaces ; 11(42): 38779-38788, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31564106

RESUMO

The most critical reason for limiting the extensive study and promotion of MA-based perovskites is their intrinsic instability when compared to FA-based perovskites. Therefore, it is necessary to develop a simple and effective method to improve their intrinsic stability. Herein, the 1,1,1-trimethylhydrazinium cation (TMH+) was first introduced into MAPbI3 to fabricate high-performance mixed-cation perovskite solar cells (PSCs) with an enhanced power conversion efficiency (PCE) of 19.86%, which benefits by the improved crystallization and morphology of films. On the one hand, the slightly large size of TMH+ is complementary to the low tolerance factor of MAPbI3 and then enhances the structure stability. On the other hand, the presence of methyl groups in TMH+ is beneficial to promote the hydrophobicity of MA-based perovskite. More importantly, the hydrazinium group can effectively inhibit the production of Pb0 in perovskites, which is the initial stage of degradation. As a result, the intrinsic stability of PSCs has been observably boosted. After aging at 45 ± 5% RH for 1800 h and 85 °C for 200 h, the unencapsulated PSCs retained 77 and 79% of initial PCE, respectively. This work provides a new design for the selection of suitable cations with special structures and chemical groups to enhance the moisture resistance and intrinsic stability of MA-based perovskite at the source of degradation.

8.
Sci Rep ; 9(1): 13813, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554880

RESUMO

Plant litter is an important component in wetland ecosystems, and the role of plant litter decomposition is considered to be important for wetland ecosystem functions and services. However, the consequences of litter inputs have seldom been experimentally tested in real ecosystems such as constructed wetlands (CWs). The enriched nutrients in CWs might weaken the role of litter inputs on soil carbon and nitrogen cycling. Here, we conducted a two-month field experiment to examine the effects of litter inputs on the soils in CWs. Our results showed that litter inputs significantly affected soil microbial (bacterial and fungi) diversities and properties (soil total nitrogen and nitrogen isotopes), and litter species with higher stoichiometry ratios, i.e. C/N, C/P and N/P led to higher microbial diversities. However, litter species had no or weak effects on microbial activities (CO2 and CH4 flux) or on the relative abundance of microbial communities, indicating that other environmental factors in such a CW might have stronger effects on those factors than litter inputs. These results highlighted the importance of submerged plant litter in nutrient-rich wetland ecosystems and provide potential tools for managers to improve the ecosystem functions and/or services via altering microbial diversities.

9.
Ecol Evol ; 9(15): 8714-8723, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31410274

RESUMO

Examining the coordination of leaf and fine root traits not only aids a better understanding of plant ecological strategies from a whole-plant perspective, but also helps improve the prediction of belowground properties from aboveground traits. The relationships between leaf and fine root traits have been extensively explored at global and regional scales, but remain unclear at local scales. Here, we measured six pairs of analogous leaf and fine root traits related to resource economy and organ size for coexisting dominant and subordinate vascular plants at three successional stages of temperate forest swamps in Lingfeng National Nature Reserve in the Greater Hinggan Mountains, NE China. Leaf and fine root traits related to resource acquisition (e.g., specific leaf area [SLA], leaf N, leaf P, root water content, and root P) decreased with succession. Overall, we found strong linear relationships between leaf dry matter content (LDMC) and root water content, and between leaf and root C, N, and P concentrations, but only weak correlations were observed between leaf area and root diameter, and between SLA and specific root length (SRL). The strong relationships between LDMC and root water content and between leaf and root C, N, and P held at the early and late stages, but disappeared at the middle stage. Besides, C and P of leaves were significantly correlated with those of roots for woody plants, while strong linkages existed between LDMC and root water content and between leaf N and root N for herbaceous species. These results provided evidence for the existence of strong coordination between leaf and root traits at the local scale. Meanwhile, the leaf-root trait relationships could be modulated by successional stage and growth form, indicating the complexity of coordination of aboveground and belowground traits at the local scale.

10.
Ecol Evol ; 9(16): 9376-9384, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31463028

RESUMO

Allochthonous (e.g., riparian) plant litter is among the organic matter resources that are important for wetland ecosystems. A compact canopy of free-floating vegetation on the water surface may allow for riparian litter to remain on it for a period of time before sinking to the bottom. Thus, we hypothesized that canopy of free-floating vegetation may slow decomposition processes in wetlands. To test the hypothesis that the retention of riparian leaf litter on the free-floating vegetation in wetlands affects their subsequent decomposition on the bottom of wetlands, a 50-day in situ decomposition experiment was performed in a wetland pond in subtropical China, in which litter bags of single species with fine (0.5 mm) or coarse (2.0 mm) mesh sizes were placed on free-floating vegetation (dominated by Eichhornia crassipes, Lemna minor, and Salvinia molesta) for 25 days and then moved to the pond bottom for another 25 days or remained on the pond bottom for 50 days. The leaf litter was collected from three riparian species, that is, Cinnamomum camphora, Diospyros kaki, and Phyllostachys propinqua. The retention of riparian leaf litter on free-floating vegetation had significant negative effect on the carbon loss, marginal negative effects on the mass loss, and no effect on the nitrogen loss from leaf litter, partially supporting the hypothesis. Similarly, the mass and carbon losses from leaf litter decomposing on the pond bottom for the first 25 days of the experiment were greater than those from the litter decomposing on free-floating vegetation. Our results highlight that in wetlands, free-floating vegetation could play a vital role in litter decomposition, which is linked to the regulation of nutrient cycling in ecosystems.

11.
Arch Pharm (Weinheim) ; 352(8): e1900024, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31338897

RESUMO

A series of novel 3-(thiophen-2-ylthio)pyridine derivatives as insulin-like growth factor 1 receptor (IGF-1R) inhibitors was designed and synthesized. IGF-1R kinase inhibitory activities and cytotoxicities against HepG2 and WSU-DLCL2 cell lines were tested. For all of these compounds, potent cancer cell proliferation inhibitory activities were observed, but not through the inhibition of IGR-1R. Selected compounds were further screened against various kinases. Typical compound 22 (50% inhibitory concentration [IC50 ] values, HepG2: 2.98 ± 1.11 µM and WSU-DLCL2: 4.34 ± 0.84 µM) exhibited good inhibitory activities against fibroblast growth factor receptor-2 (FGFR2), FGFR3, epidermal growth factor receptor, Janus kinase, and RON (receptor originated from Nantes), with IC50 values ranging from 2.14 to 12.20 µM. Additionally, the cell-cycle analysis showed that compound 22 could arrest HepG2 cells in the G1/G0 phase. Taken together, all the experiments confirmed that the compounds in this series were multitarget anticancer agents worth further optimizing.

12.
Curr Med Sci ; 39(4): 653-657, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31347004

RESUMO

18F-labeled fluorodeoxyglucose positron emission tomography (18F-FDG PET) is the most sensitive tool for studying brain metabolism in vivo. We investigated the image patterns of 18F-FDG PET during reperfusion injury and correlated changes of whole brain blood flow utilizing a rat myocardial ischemia/reperfusion injury (MIRI) model. The results assessed by echocardiography indicated resultant cardiac dysfunction after ischemia-reperfusion in the rat heart. It was found that the average standardized uptake value (SUVaverage) of the whole brain was significantly decreased in model rats, and the glucose uptake of different brain regions including accumbens core/shell (Acb), left caudate putamen (LCPu), hippocampus (HIP), left hypothalamus (LHYP), olfactory (OLF), superior colliculus (SC), right midbrain (RMID), ventral tegmental area (VTA), inferior colliculus (IC) and left thalamus whole (LTHA) was significantly decreased in MIRI rats whereas no significant difference was found in the SUVaverage of amygdala (AMY), right CPu, RHYP, right HYP, left MID, right THA, pons and medulla oblongata (MO). These 18F-FDG PET data provide a reliable identification method for brain metabolic changes in rats with MIRI.


Assuntos
Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Traumatismo por Reperfusão Miocárdica/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Animais , Encéfalo/irrigação sanguínea , Modelos Animais de Doenças , Fluordesoxiglucose F18/farmacologia , Humanos , Traumatismo por Reperfusão Miocárdica/sangue , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Ratos
13.
Plasmid ; 105: 102420, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31265838

RESUMO

Eukaryotic inducible overexpression systems, including Tet-On and mifepristone-inducible systems, have been widely used to study gene functions by reverse genetics. Among the transposon systems reported to date, the piggyBac transposon system is one of the most efficient in cultured mammalian cells. Here, we report a piggyBac-based double-inducible system that combined the advantages of previous systems. To create this system, the trans- and cis-elements of the Tet-On and mifepristone-inducible systems were cloned into a piggyBac-based trans-vector and cis-vector, respectively. The coding regions of two splicing variants of RUNX1, RUNX1a and RUNX1b, were inserted into the cis-vector to test its ability to express foreign genes along with fluorescent marker proteins. Transgenic 293 T cells were established, and the system was tested by inducing expression of foreign genes with DOX and/or mifepristone; GFP and/or mCherry were used as reporter genes. The system efficiently and stringently induced expression of GFP/mCherry and their co-expressed genes without significant mutual interference, as determined by qRT-PCR and Western blot. This piggyBac-based double-inducible system represents a new genetic tool for studying gene functions and interactions in vitro and in vivo in almost all organisms.

14.
Sci Total Environ ; 693: 133477, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31362230

RESUMO

Suaeda salsa is a pioneer species in coastal wetlands of East Asia and recently an ecosystem engineer species, Phragmites australis, has started to enter into S. salsa communities owing to either autogenic or external drivers. The consequences of this phenomenon on the ecosystem functions of coastal wetlands are still unclear, especially for decomposition processes. Here we compared the decomposition rate of S. salsa litter, and associated litter chemistry dynamics, between sites with and without P. australis encroachment. We conducted a litter transplantation experiment to tease apart the effects of litter quality and decomposing environment or decomposer community composition. Our results showed that P. australis encroachment led to higher carbon and phosphorus losses of S. salsa litter, but equal losses of total mass, lignin, hemicellulose and nitrogen. Phragmites australis encroachment might affect decomposition rate indirectly by making S. salsa produce litter with higher lignin concentrations or via increasing the fungal diversity for decomposition. Moreover, P. australis as an ecosystem engineer might also alter the allocation of total phosphorus between the plants and the soils in coastal wetlands. Our findings indicate that P. australis could impact aboveground and belowground carbon and nutrient dynamics in coastal wetlands, and highlight the important consequences that encroaching plant species, especially ecosystem engineers, can have on ecosystem functions and services of coastal wetlands, not only in East Asia but probably also elsewhere in the world.


Assuntos
Chenopodiaceae/fisiologia , Cadeia Alimentar , Invertebrados/fisiologia , Poaceae/fisiologia , Microbiologia do Solo , Áreas Alagadas , Animais , Fenômenos Fisiológicos Bacterianos , Biodiversidade , Fungos/fisiologia , Herbivoria , Microbiota/fisiologia
15.
Stem Cell Reports ; 13(1): 31-47, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31178416

RESUMO

GATA2 is essential for the endothelial-to-hematopoietic transition (EHT) and generation of hematopoietic stem cells (HSCs). It is poorly understood how GATA2 controls the development of human pluripotent stem cell (hPSC)-derived HS-like cells. Here, using human embryonic stem cells (hESCs) in which GATA2 overexpression was induced by doxycycline (Dox), we elucidated the dual functions of GATA2 in definitive hematopoiesis before and after the emergence of CD34+CD45+CD90+CD38- HS-like cells. Specifically, GATA2 promoted expansion of hemogenic precursors via the EHT and then helped to maintain HS-like cells in a quiescent state by regulating cell cycle. RNA sequencing showed that hPSC-derived HS-like cells were very similar to human fetal liver-derived HSCs. Our findings will help to elucidate the mechanism that controls the early stages of human definitive hematopoiesis and may help to develop a strategy to generate hPSC-derived HSCs.

16.
J Ethnopharmacol ; 240: 111938, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077780

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Spatholobus suberectus Dunn is a traditional Chinese medicine (TCM) that can activate blood, dispel stasis, inhibit platelet aggregation, and stimulate hematopoiesis, and thereby treat anemia and diseases related to blood stasis syndrome (BSS). However, its hematopoiesis-stimulating activity is not well understood. AIM OF STUDY: Four phenolic compounds (daidzein, formononetin, catechin, and procyandin B2) were isolated and purified from stems of S. suberectus, and tested using an in vitro hematopoiesis system. MATERIALS AND METHODS: An AGM-S3 co-culture system for hematopoiesis derived from human embryonic stem cells (hESCs) was employed to explore effects on hematopoiesis. At different stages, extracts from Spatholobus suberectus Dunn were added to the co-culture system at concentrations of 2, 10, or 50 µM, and fluorescence-activated cell sorting (FACS), hematopoietic colony culturing, and quantitative reverse transcription PCR (qRT-PCR) were used to probe changes in hematopoietic progenitors and erythroid progenitors. RESULTS: When H1 hESCs co-cultured with AGM-S3 were added along with 10 µM catechin from day 12 (D12), proliferation and differentiation of hematopoietic and erythroid progenitors from hESCs was increased based on FACS with antibodies recognizing CD34/CD45 and GPA/CD71. Hematopoiesis colony culturing further confirmed the promotion effect of catechin on hematopoiesis, and other active fractions did not significantly promote hematopoiesis. qRT-PCR revealed that some important genes related to hematopoiesis and erythroid were up-regulated followed catechin exposure. CONCLUSIONS: Our results demonstrate that catechin, an active ingredient of Spatholobus suberectus Dunn, can increase the efficiency of hematopoiesis, including hematopoietic and erythroid progenitors, consistent with previous reports. The AGM-S3 co-culture system could provide an effective tool for screening active compounds in TCMs that promote hematopoiesis, and may be of clinical and pharmaceutical use.


Assuntos
Técnicas de Cocultura , Fabaceae , Flavonoides/farmacologia , Hematopoese/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Flavonoides/isolamento & purificação , Humanos , Medicina Tradicional , Caules de Planta
17.
Artigo em Inglês | MEDLINE | ID: mdl-31091789

RESUMO

The perfluoroalkyl substances (PFAAs) have received growing attention in recent years as emerging contaminants in the aquatic environment. The occurrence, removal and bioaccumulation of fourteen PFAAs (C4-C14 carboxylate; C4, C6, C8 sulfonates) were investigated in Lake Chaohu, China. The concentrations of the selected PFAAs in inflowing river, lake water and sewage treatment plant (STP) samples were analyzed by ultra performance liquid chromatograph (UPLC-MS/MS). The results showed that perfluorohexanesulfonic acid (PFHxS), perfluorobutane sulfonate (PFBS), perfluorobutyric acid (PFBA) and perfluoropentanoic acid (PFPeA), instead of perfluorooctanoic acid (PFOA), were predominant PFAAs in the inflowing river and lake water with maximum concentrations in the ranges of 52.2-1866 and 27-236 ng L-1, respectively. The highest concentrations of total PFAAs were detected in the western rivers. The effluents from seven STPs were likely important sources of PFAAs in surface water, and the amount of the daily fluxes in the effluent were 132 g for short-chain PFAAs and 109 g for long-chain PFAAs. PFAAs were widely detected in Chinese icefish (Neosalanx tangkahkeii taihuensis) collected from Lake Chaohu, with maximal concentrations ranging from 1.79 ng g-1 to 50.9 ng g-1. The logarithmic bioaccumulation factors of perfluorodecanoic acid (PFDA, 3.5), perfluorooctane sulfonate (PFOS, 3.35) and perfluorononanoic acid (PFNA, 3.31) indicated the bioaccumulation of these long-chain PFAAs. This study is useful for enhancing our understanding of the pollution profiles of PFAAs and their environmental health risk in the freshwater lake.


Assuntos
Ácidos Graxos/análise , Fluorcarbonetos/análise , Ácidos Sulfônicos/análise , Animais , China , Cromatografia Líquida , Monitoramento Ambiental , Peixes , Lagos/química , Rios/química , Espectrometria de Massas em Tandem , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise
18.
Environ Sci Pollut Res Int ; 26(8): 8248-8256, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30701469

RESUMO

In wetland ecosystems, vegetation can float freely on water surface, forming dense canopy which may play important ecological roles. This is especially true in many urban wetlands in which fluidity is low and nutrient level is high. So far, effects of free-floating vegetation on abiotic and biotic factors of wetlands have been known, while little on wetland ecosystem functions such as litter decomposition. To examine whether the canopy of free-floating vegetation on water surface will influence litter decomposition in wetlands or not, we conducted a 50-day in situ decomposition experiment in a subtropical urban pond wetland, in which litter bags of nine combinations of three mesh sizes and three litter species were put on the bottoms of total 22 ponds which were half with and half without free-floating vegetation canopy on the water surface. The ponds with and without the canopy had different water physicochemical properties. Overall, the canopy, the species identity, and the mesh size significantly decelerated mass loss and carbon loss of leaf litters while slightly on nitrogen loss. Effects of the canopy on leaf litter decomposition also showed species- and mesh size-dependent. Our results suggest that free-floating vegetation on water surface can alter water environmental factors and consequently change ecosystem functioning in wetlands.


Assuntos
Folhas de Planta/fisiologia , Áreas Alagadas , Biodegradação Ambiental , Carbono/metabolismo , China , Ecossistema , Nitrogênio/metabolismo , Plantas , Tanques
19.
Asian J Surg ; 42(3): 482-487, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30377019

RESUMO

OBJECTIVE: To compare the outcomes of the en bloc and branched graft techniques for supra-aortic vessel reconstruction in total arch replacement (TAR) for acute type A aortic dissection (ATAAD). METHODS: In 53 ATAAD patients with intact supra-aortic arch vessels undergoing TAR, the arch vessels were reconstructed using the branched graft technique in 35 patients and en bloc technique in 18, i.e. reimplantation of the innominate artery and the left carotid artery (LCA) and transposition of left subclavian artery to LCA. The early and mid-term outcomes were compared between two groups. RESULTS: The selective antegrade cerebral perfusion time in en bloc group was significantly longer (33 ± 10 vs 24 ± 7 min, p = 0.001). Operative mortality was 5.7% (3/53), including 1 and 2 in the en bloc and branched graft groups, respectively (5.6% vs 5.7%, p = 0.981). Stroke occurred in 1 patient. No spinal cord injury occurred. At mean 4.3 ± 1.6 years, clinical and CT follow-up were complete in 100% and 86% (43/50). No cerebrovascular accidents or upper extremity claudication occurred. There were 4 deaths and 1 reintervention in follow-up. Survival was 88.6% and 88.9% at 3 months, and 83.3% and 88.6% at 6 months, 3 and 5 years in the en bloc and branched graft groups, respectively (p = 0.597). The arch vessels were patent in 100% (43/43) without stenosis or aneurysm. CONCLUSIONS: The modified en bloc technique could achieve comparable early and mid-term outcomes to the branched graft technique in patients undergoing TAR for ATAAD. This approach may be an alternative technique for ATAAD patients with intact supra-aortic arch vessels.


Assuntos
Aneurisma Dissecante/cirurgia , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/métodos , Doença Aguda , Adolescente , Adulto , Tronco Braquiocefálico/transplante , Artérias Carótidas/transplante , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Subclávia/cirurgia , Resultado do Tratamento , Adulto Jovem
20.
Zhongguo Gu Shang ; 31(12): 1124-1128, 2018 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-30583652

RESUMO

OBJECTIVE: To investigate the clinical effect of Lapidus operation combined with bone setting manipulation of traditional Chinese medicine in treating hallux valgus in elderly patients. METHODS: From March 2013 to October 2017, 53 elderly patients (87 feet) with hallux valgus were treated with Lapidus operation combined with bone-setting manipulation of traditional Chinese medicine, including 12 males (18 feet) and 41 females (69 feet), ranging in age from 65 to 92 years old, with an average of (76.3±4.8) years old. Visual analogue scale(VAS) was used to evaluate the degree of relief of foot pain before and 26 months after operation. American Orthopaedic Foot and Ankle Society(AOFAS) was used to evaluate the function of foot pain. The changes of hallux valgus angle(HVA angle), interphalangeal angle (IMA angle) and metatarsal wedge angle(MCA angle) were compared on X-ray films. RESULTS: All the patients were followed up, and the duration ranged from 12 to 42 months, with an average of(26.0±2.7) months. In all patients, the first metatarsal joint reached bone fusion within 6 to 8 months, with an average of 4.7 months. The preoperative VAS score was 8.06±1.44, which was significantly different from 2.14±1.98 at 26 months(P<0.05). The preoperative AOFAS score was 53.90±7.89, which was significantly different from 92.80±2.78 at 26 months(P<0.05). The HVA, IMA and MCA were significantly improved from preoperative(38.60±2.72)°, (21.90±1.91)° and(20.90±2.20)° to the latest follow-up(17.80±1.94)°, (9.70±2.56)° and(11.70±0.48)°(P<0.05). According AOFAS score, 74 feet got an excellent result, 11 good and 2 fair. CONCLUSIONS: Lapidus operation combined with bone-setting manipulation of traditional Chinese medicine on the treatment of hallux valgus foot in elderly patients has satisfactory clinical effects, shortens the time of osteotomy and fixation, protects the soft tissue around the osteotomy end and promotes the bone fusion on the most satisfactory position.


Assuntos
Hallux Valgus , Ossos do Metatarso , Articulação Metatarsofalângica , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Osteotomia , Radiografia , Resultado do Tratamento
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