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2.
J Nanosci Nanotechnol ; 20(2): 1170-1176, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383117

RESUMO

This brief paper reported an Ag/Al2O3 catalyst of high catalytic performance in C3H6-SCR (selective catalytic reduction with C3H6 as the reducer), and demonstrated a new strategy for the preparation of high active Ag/Al2O3 catalyst by the coupling co-precipitation and impregnation method. The results show that the coupling co-precipitation and impregnation catalyst was higher active than the usual impregnated catalyst in C3H6-SCR of NO with broad active temperature window (420-600 °C), and the highest conversions of NO achieved 91% over the coupling co-precipitation and impregnation catalyst at 500 °C. The porous structure parameter, crystal phase structure, surface acidity property and particle morphology of the Ag/Al2O3 catalyst were characterized by the Brunauer-Emmett-Teller (BET) method, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis spectra and temperature programmed desorption of ammonia (NH3-TPD), respectively. Based on the characterization, it is found that the catalyst prepared by the coupling co-precipitation and impregnation method has smaller particles and better dispersion than the usual impregnated catalyst, and so the catalyst exhibited excellent catalytic activity. NH3-TPD results illustrate that the weak and medium-strong acid sites is conducive to the reactivity of catalyst.

3.
J Nanosci Nanotechnol ; 20(1): 564-567, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383211

RESUMO

A polycrystalline BiFeO3 film was deposited on ITO substrate by RF magnetron sputtering method. Small crystallite size and compact structure are obtained for BiFeO3 film which has the excellent ferroelectric properties. The measured photovoltaic response reveals an open-circuit voltage of ~0.52 V and a short-circuit current density of ~10 µA/cm² under the illumination of 100 mW/cm² irradiance. Moreover, a tunable photovoltaic effect with light illumination is observed under different voltage sweep mode. High initial sweep voltage can enhance the photovoltaic effect largely, however, the photovoltaic response decreases with the increase of voltage sweep interval. The results indicate the ferroelectric polarization plays an important role in the photovoltaic effect.

4.
Talanta ; 207: 120260, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594598

RESUMO

Metabolomics tactics have been applied in the research associated with embryonic zebrafish. However, the report regarding the evaluation of impacts of sample pretreatment on metabolomics results from zebrafish embryos is limited. In the present study, different data normalization approaches, extraction solvents, and extraction strategies for off-line derivatization gas chromatography coupled with mass spectrometry-based metabolomics analysis of zebrafish eleutheroembryos were evaluated and optimized. The results showed that, when 4-chlorophenylalanine normalization, sample homogenization and pure methanol combined with ultrasonic extraction were conducted, better repeatabilities, higher signals and broader coverages of detected metabolites can be achieved. The recovery and standard deviation of most standards were in the range of 82%-121% and 6.6%-12%, respectively, while the relative standard deviation of major detected metabolites ranged from 5.4% to 19%, indicating good extraction efficiencies and method precision. Under the developed method, 87 important endogenous metabolites such as citric acid and hypoxanthine were identified by universal databases or standards among 270 extracted metabolites, which consisted of sugars, amines, amino acids, nucleotides, fatty acids, and sterols. Therefore, the results could provide a proper pretreatment protocol for the analysis of wide-coverage metabolome in embryonic zebrafish. In addition, this study highlights the impact of normalization and extraction methods on the data quality of metabolomics analysis.

5.
J Nanosci Nanotechnol ; 20(4): 2617-2621, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492285

RESUMO

Pure phase polycrystalline BiFeO3 film was deposited onto FTO substrate by RF magnetron sputtering method. SEM result shows that BiFeO3 film has the obvious porosity and large clusters which lead to the poor ferroelectric and photovoltaic properties in FTO/BiFeO3/Ag device. However, these properties are improved in p-i-n structured FTO/TiO2/BiFeO3/HTM/Ag device by incorporating the electron and hole transport materials. The hysteresis loop measurement demonstrates the excellent ferroelectric property with large remnant polarization (2Pr = 180 µC/cm²) and low leakage current. The J-V curve shows the short-circuit current density is dozens of times larger than that of FTO/BiFeO3/Ag device. Moreover, the photovoltaic output depends on the poling field where the positive poling improves the short-circuit current density to -85 µA/cm2 and the negative poling reduces both the photocurrent and photovoltage. It is believed that the ferroelectric polarization plays a dominant role in the photovoltaic effect.

6.
Theranostics ; 9(24): 7200-7209, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695762

RESUMO

Reactive oxygen species (ROS)-generating anticancer agents can act through two different mechanisms: (i) elevation of endogenous ROS production in mitochondria, or (ii) formation/delivery of exogenous ROS within cells. However, there is a lack of research on the development of ROS-generating nanosystems that combine endogenous and exogenous ROS to enhance oxidative stress-mediated cancer cell death. Methods: A ROS-generating agent based on polymer-modified zinc peroxide nanoparticles (ZnO2 NPs) was presented, which simultaneously delivered exogenous H2O2 and Zn2+ capable of amplifying endogenous ROS production for synergistic cancer therapy. Results: After internalization into tumor cells, ZnO2 NPs underwent decomposition in response to mild acidic pH, resulting in controlled release of H2O2 and Zn2+. Intriguingly, Zn2+ could increase the production of mitochondrial O2·- and H2O2 by inhibiting the electron transport chain, and thus exerted anticancer effect in a synergistic manner with the exogenously released H2O2 to promote cancer cell killing. Furthermore, ZnO2 NPs were doped with manganese via cation exchange, making them an activatable magnetic resonance imaging contrast agent. Conclusion: This study establishes a ZnO2-based theranostic nanoplatform which achieves enhanced oxidative damage to cancer cells by a two-pronged approach of combining endogenous and exogenous ROS.

7.
Bioresour Technol ; 296: 122340, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31704601

RESUMO

A biological aerated filter (BAF) with sulfur and pyrite as fillers were structured to simultaneously remove NH4+-N, NO3--N and PO43--P from secondary effluent. When dissolved oxygen (DO) was 1.2-1.5 mg/L, effluent concentration of NH4+-N, NO3--N and PO43--P were below 0.65, 0.47 and 0.18 mg/L, respectively. Meanwhile, Fe2+ production via decomposing pyrite could improve autotrophic denitrification performance. Besides, sulfur and pyrite autotrophic denitrification process (PAD and SAD) aligned with the Zero-order and First-order kinetics models, respectively, indicating that the sulfur had excellent capability of providing electron. Moreover, there was a positive correlation between the nitrogen removal performance and protein-like substances in extracellular polymeric substances. Bacterial community analysis suggested the nitrifiers and autotrophic denitrifiers were simultaneously enriched. Principal component analysis indicated that the DO concentration and type of electron donors impacted bacterial community. Consequently, BAF combined with PAD and SAD processes provides an alternative method to remove nutrients.

8.
Zootaxa ; 4629(2): zootaxa.4629.2.5, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31712522

RESUMO

A new winter stonefly species of the genus Capnia Pictet, 1841, Capnia s.l. bilobata sp. nov. is described and illustrated from Shaanxi Province of northwestern China. The new species is distinguished from all currently known Capnia s.l. by the male and female genitalic characters. The falciform projection on male tergum 9 and the unique-shaped female subgenital plate separate the new taxon from other congeners.


Assuntos
Insetos , Lepidópteros , Distribuição Animal , Animais , China , Feminino , Masculino , Neópteros
9.
Zootaxa ; 4576(3): zootaxa.4576.3.11, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31715756

RESUMO

Leptobrachella (Anura: Megophryidae) is currently composed of seventy-one species distributed in China and Southeast Asia (Frost 2018). Fourteen species of Leptobrachella are currently known from southern China: L. alpina (Fei, Ye Li, 1990), L. laui (Sung, Yang Wang, 2014), L. liui (Fei Ye, 1990), L. mangshanensis (Hou, Zhang, Hu, Li, Shi, Chen, Mo Wang, 2018), L. maoershanensis (Yuan, Sun, Chen, Rowley Che, 2017), L. oshanensis (Liu, 1950), L. purpura (Yang, Zeng Wang, 2018), L. tengchongensis (Yang, Wang, Chen Rao, 2016), L. wuhuangmontis (Wang, Yang Wang, 2018), L. yingjiangensis (Yang, Zeng Wang, 2018), L. yunkaiensis (Wang, Li, Lyu Wang, 2018), L. ventripunctata (Fei, Ye Li, 1990), L. pelodytoides (Boulenger, 1893) and L. sungi (Lathrop, Murphy, Orlov Ho, 1998) and the first eleven species are endemic of this region (AmphibiaChina 2018). Many new species in this genus were discovered based on molecular, morphometric and bioacoustic data in recent years (Frost 2018). In comparison to molecular and morphological data, bioacoustics is especially useful in species identification of Leptobrachella in field surveys (Rowley et al. 2016). Although the advertisement calls of many Leptobrachella species were described along with the species descriptions (e.g., Rowley et al. 2016), the advertisement calls of only three Chinese endemic species (L. alpinus; L. laui and L. oshanensis) are known (Jiang et al. 2002; Matsui 2006; Xu et al. 2005). Here, we describe the advertisement calls of L. liui, which inhabits rocky streams in southeastern China (Fujian, Jiangxi and Zhejinag) and is morphologically diagnosed by the combination of a set of external color traits (Fig. 1).


Assuntos
Anuros , Gastrópodes , Animais , China , Cor , Fenótipo
10.
J Virol Methods ; : 113774, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31726113

RESUMO

Porcine Reproductive and Respiratory Syndrome (PRRS), an acute infectious disease caused by the porcine reproductive and respiratory syndrome virus (PRRSV), is one of the most devastating diseases affecting the global swine industry. In order to establish a multiplex real-time PCR method for the simultaneous detection of the classical PRRSV (C-PRRSV) strain, the highly pathogenic PRRSV (HP-PRRSV) strain and NADC30-like PRRSV (NL-PRRSV) strain, we designed specific primers and TaqMan fluorescent probes based on the Nsp2 target gene sequence of these three different PRRSV strains, and designed American-type PRRSV (PRRSV-U) special primers and probes based on the relatively conserved target gene sequence of ORF7. The method established in this study can quickly and accurately detect and differentiate three types of strains of clinical tissue samples, respectively. This method plays a key role in the rapid diagnosis and determination of PRRSV.

11.
J Cell Biochem ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31692090

RESUMO

Cellular differentiation is caused by highly controlled modifications in the gene expression but rarely involves a change in the DNA sequence itself. Histone acetylation is a major epigenetic factor that adds an acetyl group to histone proteins, thus altering their interaction with DNA and nuclear proteins. Illumination of the histone acetylation during dentinogenesis is important for odontoblast differentiation and dentinogenesis. In the current study, we aimed to discover the roles and regulation of acetylation at histone 3 lysine 9 (H3K9ac) and H3K27ac during dentinogenesis. We first found that both of these modifications were enhanced during odontoblast differentiation and dentinogenesis. These modifications are dynamically catalyzed by histone acetyltransferases (HATs) and deacetylases (HDACs), among which HDAC3 was decreased while p300 increased during odontoblast differentiation. Moreover, overexpression of HDAC3 or knockdown p300 inhibited odontoblast differentiation in vitro, and inhibition of HDAC3 and p300 with trichostatin A or C646 regulated odontoblast differentiation. Taken together, the results of our present study suggest that histone acetylation is involved in dentinogenesis and coordinated expression of p300- and HDAC3-regulated odontoblast differentiation through upregulating histone acetylation.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31692440

RESUMO

BACKGROUND AND OBJECTIVE: Swertia mussotii Franch, also known as "Zangyinchen",is one of a Tibetan traditional herb used for treatment of liver diseases over thousands of years at Qinghai-Tibet Plateau, has been confirmed to be hepatoprotective. However, the underlying mechanism is largely unknown. MATERIALS AND METHODS: In this study, we evaluated the effect of S. mussotii treatment in a carbon tetrachloride-induced acute liver injury rat model by examining the serum alanine aminotransferase, aspartate aminotransferase, total bilirubin levels and performing histological observations of the liver tissues. Meanwhile, the metabolomics analysis was used to explore the molecular mechanism of SMT by high performance liquid chromatography tandem mass spectrometry. RESULTS: the results showed that SMT could effectively improve the serum alanine aminotransferase, aspartate aminotransferase, total bilirubin in acute liver injury rat model. Histological observation showed that S. mussotii treatment could effectively alleviate the liver injury. Moreover, the metabolomicsanalysis showed that S. mussotii treatment could normalize the levels of many fatty acid metabolism related metabolites. And the results of pathway analysis showed that these metabolites significantly enriched in fatty acid biosynthesis pathway (myristic acid, dodecanoic acid and capric acid) and linoleic acid metabolism pathway (13-OxoODE). CONCLUSION: The results indicated that S. mussotii treatment could significantly improve the acute liver injury through affecting the pathways related to lipid metabolism.

13.
Zootaxa ; 4679(3): zootaxa.4679.3.5, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31715948

RESUMO

A new brachypterous species of the perlodid genus Filchneria Klapálek 1908, F. wusuensis sp. nov. is described and illustrated from Xinjiang Uygur Autonomous Region of northwestern China. An additional unidentified specimen, Filchneria sp. is recorded from Heilongjiang Province of northeastern China. Two other perlodid genera, Arcynopteryx Klapálek, 1904 and Pictetiella Illies, 1966 are newly reported from China. The macropterous form of A. polaris Klapálek, 1912 and P. asiatica Zwick Levanidova, 1971 are reported from Jilin Province of northeastern China for the first time. Finally, an updated checklist and adult key to genera of Perlodidae known from China are provided.


Assuntos
Insetos , Lepidópteros , Distribuição Animal , Animais , China , Neópteros
14.
Zootaxa ; 4651(2): zootaxa.4651.2.6, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31716912

RESUMO

A new species of the perlodid genus Perlodinella Klapálek, 1912, P. mazehaoi sp. nov. from Inner Mongolia of northeastern China is described and illustrated based on the male, the female and eggs. The aedeagus and egg described herein are the first known for the genus Perlodinella. Morphological comparisons between the new species and congeners are given. This species is the first record of Perlodinella from Inner Mongolia.


Assuntos
Insetos , Distribuição Animal , Animais , China , Feminino , Masculino , Óvulo
15.
Zootaxa ; 4651(2): zootaxa.4651.2.11, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31716917

RESUMO

A new species of the perlodid genus Isoperla Banks, 1906, Isoperla qinlinga Chen, sp. nov. from Shaanxi Province of northwestern China is described. The new species is characterized by the mostly dark head and pronotum, the poorly developed vesicle, the modified ventral and dorsal aedeagal lobes, and the slightly developed, rounded subgenital plate of the female. Comments are provided on the known species of Isoperla of China.


Assuntos
Insetos , Animais , China , Feminino , Neópteros
16.
Zootaxa ; 4586(3): zootaxa.4586.3.11, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31716124

RESUMO

A new species of the perlodid genus Neofilchneria Zwick, 1973, Neofilchneria wanglanga sp. nov. from Sichuan Province of southwestern China is described. The new species is distinctive in both the male and female adult distinguishing it from the two known congeners. The discovery of this species extends the distribution of Neofilchneria from the eastern Himalayas to southwestern China. A provisional key to the adults of Neofilchneria is provided.


Assuntos
Insetos , Distribuição Animal , Animais , China , Feminino , Masculino , Neópteros
17.
Zootaxa ; 4624(2): zootaxa.4624.2.6, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31716225

RESUMO

Paraleuctra cuihuashana sp. nov., the first formally reported brachypterous stonefly of Leuctridae (Plecoptera) known from China, is described from Shaanxi Province of northwestern China. The new species is characterized by the short-winged male with unique hindwing venation and a finger-shaped process on cerci. The female of P. cuihuashana sp. nov. has variable wing length. Molecular data supported the distinctness of the new species and the widespread P. orientalis (Chu, 1928).


Assuntos
Insetos , Lepidópteros , Animais , China , Feminino , Masculino , Neópteros , Asas de Animais
18.
Zootaxa ; 4623(1): zootaxa.4623.1.13, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31716283

RESUMO

A new species of Filchneria Klapálek 1908, F. songi sp. nov. from Shaanxi Province of northwestern China is described and illustrated based on male, female, and eggs. Morphological comparisons are provided with related taxa. Skwala compacta (McLachlan, 1872) is newly recorded from Xinjiang Uygur Autonomous Region of northwestern China. New illustrations are provided for Chinese specimens of S. compacta.


Assuntos
Insetos , Distribuição Animal , Animais , China , Feminino , Masculino , Óvulo
19.
Zootaxa ; 4619(3): zootaxa.4619.3.8, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31716294

RESUMO

A new species of the peltoperlid genus Microperla Chu, 1928, Microperla qinlinga Chen, sp. nov. from Shaanxi Province of northwestern China is described and illustrated. The new species is characterized by the widely rounded ventral lobe in males and the extremely large and bilobed subgenital plate in female. In addition, the taxonomic history and current status of the genus Microperla is reviewed.


Assuntos
Insetos , Distribuição Animal , Animais , China , Feminino , Masculino , Neópteros
20.
Zootaxa ; 4613(2): zootaxa.4613.2.8, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31716417

RESUMO

Additional specimens of Neoperla caii Li Wang, 2017 are recorded from Sichuan Province of southwestern China. Morphological variation in the adult male is discussed and illustrated. The adult female of N. caii is described and illustrated for the first time. In addition, a new species, Kamimuria petasus sp. nov. is described from Sichuan Province. The adult male of this new species is characterized by subtriangular basal callus on the hemitergal lobe and by the aedeagus with a hat-shaped apex.


Assuntos
Insetos , Distribuição Animal , Animais , China , Feminino , Masculino , Neópteros
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