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1.
ACS Appl Mater Interfaces ; 13(41): 49482-49489, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34636536

RESUMO

Although organic artificial enzymes have been reported as biomimetic oxidation catalysts and are widely used for colorimetric biosensors, developing organic artificial enzymes with high enzymatic activity is still a challenge. Two-dimensional (2D) covalent organic frameworks (COFs) have shown superior potential in biocatalysts because of their periodic π-π arrays, tunable pore size and structure, large surface area, and thermal stability. The interconnection of electron acceptor and donor building blocks in the 2D conjugated COF skeleton can lead to narrower band gaps and efficient charge separation and transportation and thus is helpful to improve catalytic activity. Herein, a donor-acceptor 2D COF was synthesized using tetrakis(4-aminophenyl)pyrene (Py) as an electron donor and thieno[3,2-b]thiophene-2,5-dicarbaldehyde (TT) as an electron acceptor. Under visible light irradiation, the donor-acceptor 2D COF exhibited superior enzymatic catalytic activity, which could catalyze the oxidation of chromogenic substrates such as 3,3',5,5'-tetramethylbenzidine (TMB) by the formation of superoxide radicals and holes. Based on the above property, the photoactivated donor-acceptor 2D COF with enzyme-like catalytic properties was designed as a robust colorimetric probe for cheap, highly sensitive, and rapid colorimetric detection of glutathione (GSH); the corresponding linear range of GSH was 0.4-60 µM, and the limit of detection was 0.225 µM. This study not only presents the construction of COF-based light-activated nanozymes for environmentally friendly colorimetric detection of GSH but also provides a smart strategy for improving nanozyme activity.

2.
Plants (Basel) ; 10(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34579466

RESUMO

Eucommia ulmoides Oliver is a woody plant with great economic and medicinal value. Its dried bark has a long history of use as a traditional medicinal material in East Asia, which led to many glycosides, such as aucubin, geniposide, hyperoside, astragalin, and pinoresinol diglucoside, being recognized as pharmacologically active ingredients. Uridine diphosphate glycosyltransferases (UGTs) catalyze a glycosyl-transferring reaction from the donor molecule uridine-5'-diphosphate-glucose (UDPG) to the substrate, which plays an important role in many biological processes, such as plant growth and development, secondary metabolism, and environmental adaptation. In order to explore the biosynthetic pathways of glycosides in E. ulmoides, 91 putative EuUGT genes were identified throughout the complete genome of E. ulmoides through function annotation and an UDPGT domain search. Phylogenetic analysis categorized them into 14 groups. We also performed GO annotations on all the EuUGTs to gain insights into their functions in E. ulmoides. In addition, transcriptomic analysis indicated that most EuUGTs showed different expression patterns across diverse organs and various growing seasons. By protein-protein interaction predication, a biosynthetic routine of flavonoids and their glycosides was also proposed. Undoubtedly, these results will help in future research into the biosynthetic pathways of glycoside compounds in E. ulmoides.

3.
Talanta ; 233: 122497, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215115

RESUMO

Highly specific capture of phosphopeptides, especially multi-phosphopeptides, from complex biological samples is critical for comprehensive phosphoproteomic analysis, but it still poses great challenges due to the lack of affinity material with ideal enrichment efficiency. Here, two-dimensional (2D) covalent organic framework (COFs) nanosheets was applied for selective separation of phosphopeptides for the first time. Particularly, by incorporating guanidinium units, the 2D guanidinium-based COF nanosheets (denoted as TpTGCl CONs) exhibited controllable and specific enrichment performance towards global/multi-phosphopeptides. TpTGCl CONs was easy to prepare and showed large surface area, low steric hindrance, abundant accessible interaction sites and high chemical stability. Taking these merits together, TpTGCl CONs exhibited excellent efficiency for phosphopeptide enrichment, such as low detection limits (0.05 fmol µL-1 for global phosphopeptides and 0.1 fmol µL-1 for multi-phosphopeptides), high selectivity (1:5000 of molar ratios of ß-casein/BSA for both global and multi-phosphopeptides), high adsorption capacity (100 mg g-1 for global phosphopeptides and 50 mg g-1 for multi-phosphopeptides). Furthermore, TpTGCl CONs could be reused due to the high chemical stability. In addition, TpTGCl CONs were successfully applied to controllable and specific capture of endogenous global/multi-phosphopeptides from human serum and human saliva, indicating its good potential in rapid and sensitive detection of biomarkers from biological fluid. Finally, rat liver protein digest was used to confirm the high specificity of TpTGCl CONs towards multi-phosphopeptides and demonstrated its potential as an ideal enrichment probe for comprehensive phosphoproteomic analysis.


Assuntos
Estruturas Metalorgânicas , Fosfopeptídeos , Adsorção , Cromatografia de Afinidade , Guanidina , Titânio
4.
Chem Commun (Camb) ; 57(60): 7362-7365, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34196343

RESUMO

A facile strategy was introduced for room-temperature controllable synthesis of hierarchically flower-like hollow COFs (FHF-COFs). Furthermore, the universality for synthesis of the HFH-COFs was validated by altering the building units. Inspired by the unique morphology, extremely large surface area and good chemical stability, HFH-COFs could serve as an attractive adsorption probe by loading with gold nanoparticles and be applied to enrichment of brain natriuretic peptide from human serum. This work opens up a whole new approach for controllable synthesis of the HFH-COFs at room temperature and expands the application of COFs as a promising enrichment probe for complex biological samples.


Assuntos
Estruturas Metalorgânicas/química , Peptídeo Natriurético Encefálico/isolamento & purificação , Adsorção , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/síntese química , Peptídeo Natriurético Encefálico/sangue , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
5.
J Hazard Mater ; 418: 126288, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34102358

RESUMO

Terrestrial ecosystems are widely contaminated by microplastics due to extensive usage and poor handling of plastic materials, but the subsequent fate and remediate strategy of these pollutants are far from fully understood. In soil environments, microplastics pose a potential threat to the survival, growth, and reproduction of soil microbiota that in turn threaten the biodiversity, function, and services of terrestrial ecosystems. Meanwhile, microorganisms are sensitive to microplastics due to the adaptability to changes in substrates and soil properties. Through the metabolic and mineralization processes, microorganisms are also crucial participator to the plastic biodegradation. In this review, we present current knowledges and research results of interactions between microplastics and microorganisms (both fungi and bacteria) in soil environments and mainly discuss the following: (1) effects of microplastics on microbial habitats via changes in soil physical, chemical, and biological properties; (2) effects of microplastics on soil microbial communities and functions; and (3) soil microbial-mediated plastic degradation with the likely mechanisms and potential remediation strategies. We aim to analyze the mechanisms driving these interactions and subsequent ecological effects, propose future directives for the study of microplastic in soils, and provide valuable information on the plastic bioremediation in contaminated soils.


Assuntos
Microbiota , Poluentes do Solo , Biodegradação Ambiental , Microplásticos , Plásticos/toxicidade , Solo , Poluentes do Solo/toxicidade
6.
ACS Appl Mater Interfaces ; 13(23): 27179-27187, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34087063

RESUMO

Although inverted (p-i-n) structure perovskite solar cells (PSCs) have achieved high efficiency by commonly using fullerenes or their derivatives as electron transport layers (ETLs), the device stability and cost of fullerene materials are still of great concern. Herein, we demonstrate inorganic top ETLs simply composed from a family of metal oxides including In2O3 and its derivative of Sn:In2O3 with a gradient potential structure. For inverted PSCs, the typical film formation process of In2O3 will damage or degrade perovskite materials underneath; thus, we report a low temperature synthesis approach for obtaining In2O3 and Sn:In2O3 nanoparticles that can form effective top ETLs without any post-treatment. The one-family oxide-based top ETL features with the enhanced built-in potential, high electron extraction, and low interfacial recombination, offering a power conversion efficiency (PCE) of 20.65% in PSCs constructed from oxide-only carrier (both hole and electron) transport layers (CTLs), which is the highest efficiency in oxide-only CTL-based inverted PSCs to the best of our knowledge. Equally important, the inverted PSCs based on the Sn:In2O3/In2O3 ETL show the excellent operational stability and remain 90% of the initial value of PCE over 2000 h. Consequently, this work contributes to the robust strategy of all oxide-only CTLs in developing rigid and flexible PSCs for practical photovoltaic applications.

7.
Adv Mater ; 33(15): e2008820, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33687773

RESUMO

The long-term operational stability of perovskite light-emitting diodes (PeLEDs), especially red PeLEDs with only several hours typically, has always faced great challenges. Stable ß-CsPbI3 nanocrystals (NCs) are demonstrated for highly efficient and stable red-emitting PeLEDs through incorporation of poly(maleic anhydride-alt-1-octadecene) (PMA) in synthesizing the NCs. The PMA can chemically interact with PbI2 in the precursors via the coupling effect between O groups in PMA and Pb2+ to favor crystallization of stable ß-CsPbI3 NCs. Meanwhile, the cross-linked PMA significantly reduces the PbCs anti-site defect on the surface of the ß-CsPbI3 NCs. Benefiting from the improved crystal phase quality, the photoluminescence quantum yield for ß-CsPbI3 NCs films remarkably increases from 34% to 89%. The corresponding red-emitting PeLEDs achieves a high external quantum efficiency of 17.8% and superior operational stability with the lifetime, the time to half the initial electroluminescence intensity (T50 ) reaching 317 h at a constant current density of 30 mA cm-2 .

8.
ACS Appl Mater Interfaces ; 13(14): 16611-16619, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33784076

RESUMO

In this study, we demonstrate a new hybrid three-dimensional (3D) nanostructure system as an efficient hole transport layer (HTL) by a facile design of a low-temperature solution process. It is realized by integrating high-conductive chromium-doped CuGaO2 nanoplates synthesized with choline chloride (denoted as Cr/CuGaO2-CC) into ultrasmall NiOx nanoparticles. First, we propose to incorporate a Cr-doped strategy under hydrothermal synthesis conditions together with controllable intermediates and surfactants' assistance to synthesize fine-sized Cr/CuGaO2-CC nanoplates. Subsequently, these two-dimensional (2D) nanoplates serve as the expressway for improving hole transportation/extraction properties. Meanwhile, the ultrasmall-sized NiOx nanoparticles are employed to modify the surface for achieving unique surface properties. The HTL formed from the designed hybrid 3D-nanostructured system exhibits the advantages of smooth and full-covered surface, remarkable charge collection efficiency, energy level alignment between the electrode and perovskite layer, and the promotion of perovskite crystal growth. Consequently, nearly 20% of power conversion efficiency with negligible hysteresis is achieved in inverted perovskite solar cells (PSCs). This work not only demonstrates the potential applications of a 3D-nanostructured Cr/CuGaO2-CC/NiOx hybrid HTL in PSCs but also provides a fundamental insight into the design of hybrid material systems by manipulating electric behavior and morphology structure for achieving high-performance photovoltaic devices.

9.
J Urol ; 205(1): 137-144, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32856980

RESUMO

PURPOSE: Current serum tumor markers for testicular germ cell tumor are limited by low sensitivity. Growing evidence supports the use of circulating miR-371a-3p as a superior marker for malignant (viable) germ cell tumor management. We evaluated the real-world application of serum miR-371a-3p levels in detecting viable germ cell tumor among patients undergoing partial or radical orchiectomy. MATERIALS AND METHODS: Serum samples were collected from 69 consecutive patients before orchiectomy. Performance characteristics of serum miR-371a-3p were compared with conventional serum tumor markers (⍺-fetoprotein/ß-human chorionic gonadotropin/lactate dehydrogenase) between patients with viable germ cell tumor and those without viable germ cell tumor on orchiectomy pathology. Relative miR-371a-3p levels were correlated with clinical course. The Kruskal-Wallis test and linear and ordinal regression models were used for analysis. RESULTS: For detecting viable germ cell tumor, combined conventional serum tumor markers had a specificity of 100%, sensitivity of 58% and AUC of 0.79. The miR-371a-3p test showed a specificity of 100%, sensitivity of 93% and AUC of 0.978. Median relative expression of miR-371a-3p in viable germ cell tumor cases was more than 6,800-fold higher than in those lacking viable germ cell tumor. miR-371a-3p levels correlated with composite stage (p=0.006) and, among composite stage I cases, independently associated with embryonal carcinoma percentage (p=0.0012) and tumor diameter (p <0.0001). Six patients underwent orchiectomy after chemotherapy and were correctly predicted to have presence or absence of viable germ cell tumor by the miR-371a-3p test. CONCLUSIONS: If validated, the miR-371a-3p test can be used in conjunction with conventional serum tumor markers to aid clinical decision making. A positive miR-371a-3p test in patients after preoperative chemotherapy or with solitary testes could potentially guide subsequent orchiectomy or observation.


Assuntos
Biomarcadores Tumorais/sangue , MicroRNA Circulante/sangue , MicroRNAs/sangue , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Orquiectomia , Neoplasias Testiculares/diagnóstico , Adulto , Estudos de Casos e Controles , Quimioterapia Adjuvante , Tomada de Decisão Clínica/métodos , Estudos de Viabilidade , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/sangue , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Embrionárias de Células Germinativas/terapia , Período Pré-Operatório , Neoplasias Testiculares/sangue , Neoplasias Testiculares/patologia , Neoplasias Testiculares/terapia , Testículo/patologia , Testículo/cirurgia , Conduta Expectante
10.
ACS Appl Mater Interfaces ; 12(51): 57165-57173, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33296167

RESUMO

Interfaces in perovskite solar cells (PSCs) are closely related to their power conversion efficiency (PCE) and stability. It is highly desirable to minimize the interfacial nonradiative recombination losses through rational interfacial engineering. Herein we develop an effective and easily reproducible interface engineering strategy where three mercaptobenzimidazole (MBI)-based molecules are employed to modify the perovskite/electron transport layer (ETL) interface. MBI and MBI-OCH3 can not only passivate defects at surface and grain boundaries (GBs) of perovskite films but can also improve energy level alignment (ELA), which leads to enhanced PCE and stability. Consequently, the PCE is improved from 19.5% for the control device to 21.2% for MBI-modified device, which is among the best reported inverted MAPbI3-based PSCs. In contrast, incorporation of MBI-NO2 increases defect density and negligibly influences the energy level alignment. This work indicates that defect passivation and ELA modulation can be achieved simultaneously through modulating functional groups in interface modification molecules.

11.
J Psycholinguist Res ; 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651840

RESUMO

Previous studies showed that the onset age of second language acquisition (AoA-L2) can modulate brain structure of bilinguals. However, the underlying mechanism of anatomical plasticity induced by AoA-L2 is still a question in debate. In order to explore the issue, we recruited two groups of native Cantonese-Mandarin speakers, the early group began to speak in Mandarin at about 3.5 and the late group at about 6.5 years old. In addition, the early group had earlier experience in reading Chinese characters than the late group did. Through estimating the cortical thickness (CT), we found that (1) compared with the late group, the early group had thicker CT in the lateral occipital region, left middle temporal gyrus, and left parahippocampal region, which are all involved in visuospatial processing, probably reflecting the effect induced by the earlier or later experiences in processing the characters of Chinese for the two groups; and (2) compared with the late group, the early group had thicker CT in left superior parietal region, which is believed to be involved in language switching, maybe for the early group had the earlier experience in switching back and forth between Cantonese and Mandarin and therefore recruited the executive control network earlier. Our findings revealed the effects of the AoA-L2 in oral language acquisition as well as in written language acquisition as the main determinants of bilingual language structural representation in human brain.

12.
Mikrochim Acta ; 187(7): 370, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32504203

RESUMO

Core-shell structured magnetic covalent organic framework (Fe3O4@COF) nanospheres were rapidly synthesized at room temperature using the monodisperse Fe3O4 nanoparticles (NPs) as magnetic core and benzene-1,3,5-tricarbaldehyde (BTA) and 3,3'-dihydroxybenzidine (DHBD) as two building blocks (denoted as Fe3O4@BTA-DHBD), respectively. They can serve as a mass spectrometry probe for rapid and high-throughput screening of bisphenols (BPs) from pharmaceuticals and personal care products (PPCPs) by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). The Fe3O4@BTA-DHBD nanospheres showed some superior features involving average pore size distribution (2.82 nm), high magnetization values (42.5 emu g-1), high specific surface area (82.96 m2 g-1), and good chemical/thermal stability. It was used as both ideal adsorbent for enrichment of BPs and new substrate to assist ionization in SELDI-TOF-MS. The method exhibited good linearity in the range 0.05-4000 ng mL-1 with correlation coefficients (r) higher than 0.9920. Low limits of detection (LODs) (500 pg mL-1 for bisphenol A (BPA), 2 pg mL-1 for bisphenol B (BPB), 28 pg mL-1 for bisphenol C (BPC), 60 pg mL-1 for bisphenol F (BPF), 33 pg mL-1 for bisphenol AF (BPAF), 200 pg mL-1 for bisphenol BP (BPBP), 10 pg mL-1 for bisphenol S (BPS), 90 pg mL-1 for tetrabromobisphenol A (BPA(Br)4), and 380 pg mL-1 for tetrabromobisphenol S (BPS(Br)4)) and good recoveries (80.6-115%) of BPs in PPCPs were achieved. The relative standard deviations (RSDs) of spot-to-spot (n = 10) and sample-to-sample (n = 5) were in the ranges 5-11% and 5-12%, respectively. The dual-function platform was successfully applied to the quantitative determination of BPs in PPCPs. It not only expanded the scope of the application of COFs but also provided an alternative strategy for the determination of hazardous compounds in PPCPs. Graphical abstract Schematic representation of the synthesis of core-shell structured magnetic covalent organic framework nanospheres (Fe3O4@COFs) and its application in the analysis of bisphenols by using Fe3O4@BTA-DHBD nanospheres as a MS probe based on surface-enhanced laser desorption/ionization time-of-flight mass spectrometry.

13.
Adv Mater ; 32(24): e2000186, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32363655

RESUMO

CsPbI3 inorganic perovskite has exhibited some special properties particularly crystal structure distortion and quantum confinement effect, yet the poor phase stability of CsPbI3 severely hinders its applications. Herein, the nature of the photoactive CsPbI3 phase transition from the perspective of PbI6 octahedra is revealed. A facile method is also developed to stabilize the photoactive phase and to reduce the defect density of CsPbI3 . CsPbI3 is decorated with multifunctional 4-aminobenzoic acid (ABA), and steric neostigmine bromide (NGBr) is subsequently used to further mediate the thin films' surface (NGBr-CsPbI3 (ABA)). The ABA or NG cation adsorbed onto the grain boundaries/surface of CsPbI3 anchors the PbI6 octahedra via increasing the energy barriers of octahedral rotation, which maintains the continuous array of corner-sharing PbI6 octahedra and kinetically stabilizes the photoactive phase CsPbI3 . Moreover, the added ABA and NGBr not only interact with shallow- or deep-level defects in CsPbI3 to significantly reduce defect density, but also lead to improved energy-level alignment at the interfaces between the CsPbI3 and the charge transport layers. Finally, the champion NGBr-CsPbI3 (ABA)-based inorganic perovskite solar cell delivers 18.27% efficiency with excellent stability. Overall, this work demonstrates a promising concept to achieve highly phase-stabilized inorganic perovskite with suppressed defect density for promoting its optoelectronic applications.

14.
Analyst ; 145(8): 3125-3130, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32163066

RESUMO

A spherical vinyl-functionalized covalent-organic framework (COF-V) was prepared at room temperature by a facile method and applied as a novel substrate for surface-enhanced laser desorption/ionization mass spectrometry (SELDI-MS). Compared with conventional organic matrices, the spherical COF-V with high crystallinity and good monodispersity exhibited high sensitivity, no matrix background interference, wide-range applicability, high salt tolerance and reproducibility in the characterization of small molecules. Considering these advantages, the applicability of the spherical COF-V-based SELDI-MS method was successfully demonstrated by determining trace amounts of glucose in diabetic urine, which would be a promising candidate for clinical diagnosis of diabetes. In addition, the morphological effect and the desorption/ionization mechanism of the COF-V were investigated in detail and the results indicated that the spherical COF-V substrate could greatly enhance the LDI process compared with the bulk COF-V. This work not only extends the application of COFs in MS, but also offers a promising alternative for small molecule identification and clinical diagnosis of diabetes.


Assuntos
Estruturas Metalorgânicas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Diabetes Mellitus/diagnóstico , Poluentes Ambientais/análise , Glucose/análise , Glicosúria/diagnóstico , Humanos , Limite de Detecção , Compostos Orgânicos/análise , Reprodutibilidade dos Testes
15.
ACS Appl Mater Interfaces ; 11(41): 38255-38264, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529951

RESUMO

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has become an indispensable tool for high-throughput analysis of macromolecules, but many challenges still remain in detection of small molecules due to the severe matrix-related background interference in the low-molecular-weight ranges (MW < 700 Da). Herein, a gallic acid (GA)-functionalized zirconium 1,4-dicarboxybenzene metal-organic framework (MOF) (denoted as UiO-66-GA) was designed to serve as a new substrate, and a novel strategy on the basis of the synergistic effect of MOF and GA was developed to enhance the LDI process. In comparison with conventional organic matrices, the UiO-66-GA substrate showed superior LDI performance in the analysis of a wide variety of molecules including amino acids, unsaturated fatty acids, bisphenols (BPs), oligosaccharides, peptides, protein, and polyethylene glycol (PEG) of various average molecular weights from 200 to 10000. Perfluorooctanoic sulfonate (PFOS) was used to evaluate the ability of quantitative analysis, and its corresponding limit of detection as low as 1 fmol was achieved. High sensitivity and good salt tolerance of the UiO-66-GA-assisted LDI-MS were allowed to determine ultratrace PFOS in the spiked human urine and serum samples. In addition, the synergistic mechanism of MOF and GA in the enhanced LDI process was investigated by comprehensively comparing GA- and its analogue-functionalized UiO-66, and the results revealed that two aspects contributed to the enhanced LDI process: (1) an enhancement in the metal-phenolic coordination system of UiO-66-GA promoted laser absorption and energy transfer; (2) introduction of carboxyl and hydroxyl groups of GA onto UiO-66 facilitated the LDI process in both positive and negative ion modes. This work expands a new domain for the MOF applications and provides a promising alternative for various molecule analyses.

16.
Chem Commun (Camb) ; 55(47): 6783-6786, 2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31120067

RESUMO

Redox reactions of K5Bi4 and CpCo(CO)2/Rh(CO)2(acac) (acac = acetylacetonate) in ethylenediamine (en) yielded the first Bi73- adducts [Bi7M3(CO)3]2- (M = Co, 1a; Rh, 2a) that have a new architype 10-vertex deltahedral structure, resulting from the unprecedented polycyclic η5-coordination addition reaction of the Bi73- cage and three MCO+ fragments.

17.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(3): 334-337, 2019 Mar 28.
Artigo em Chinês | MEDLINE | ID: mdl-30971528

RESUMO

OBJECTIVE: To know about the cesarean section rate and the changes of the indications for cesarean section in Changsha from 2008 to 2017, and to provide scientific basis for decreasing the cesarean section rate.
 Methods: We collected the clinical data of deliveries in a general hospital in Changsha from January 2008 to December 2017, and analyzed the cesarean section rate, the changes of the indications for cesarean section and the influential factors. 
 Results: The cesarean section rate in this hospital was 50.0% from 2008 to 2017, and the cesarean section due to social factors showed a decreasing trend year by year. Multiple-factor analysis of the cesarean section shows that advanced age, multi-parous pregnancy, gravida (≥4 times), abnormal fetal position and heavy fetus weight were dangerous factors, and the multipara was a protective factor.
 Conclusion: The cesarean section rate in a general hospital in Changsha is at a high level, and there are many factors affecting cesarean section. It is necessary to optimize the strategies and measures to reduce the cesarean section rate, and to control the cesarean section rate in a reasonable range.


Assuntos
Cesárea , Hospitais Gerais , Parto Obstétrico , Feminino , Humanos , Gravidez , Estudos Retrospectivos
18.
Int J Psychophysiol ; 137: 32-40, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30664886

RESUMO

Some studies have shown a superiority of visual vs. auditory item presentation in the Complex Trial Protocol (CTP), which is a countermeasure-resistant version of the P300-based Concealed Information Test (CIT). But those studies used elaborately- rehearsed autobiographical information as stimuli, instead of incidentally-acquired crime-related information. Thus, the relative superiority of the visual as opposed to the auditory modality in detecting episodic crime-related information is still unknown. The present study also improved on the usual mock crime scenario by adding a mock disposal task between a mock theft and administration of a CTP test to increase stimulus saliency. In this CTP, the probe and the irrelevant items were presented visually or acoustically on alternating trials, while target and non-target stimuli were simultaneously presented in visual and auditory modalities. The results showed that the P300 amplitude differences of probe minus irrelevant items presented in the visual modality were significantly larger compared to the auditory modality, and the detection rate of the guilty participants was also significantly higher for the visual (14/16) versus auditory modality (5/16). These results suggest a superiority of visual vs. auditory presentation when a CTP is used to detect crime-related information in a mock crime scenario.


Assuntos
Estimulação Acústica/métodos , Decepção , Potencial Evocado P300/fisiologia , Detecção de Mentiras , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Estimulação Acústica/psicologia , Adolescente , Adulto , Feminino , Humanos , Detecção de Mentiras/psicologia , Masculino , Adulto Jovem
19.
Langmuir ; 34(25): 7519-7526, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29852741

RESUMO

Photoresponsive liquid crystal (LC) physical gels have attracted more and more attention because of the nature of strong response via light stimulus. Although many efforts on the breaking and recovering of physical gels through photoisomerization have been focused, fast electro-optical response and high mechanical properties even upon light irradiations are difficult to achieve at the same time. In this work, two kinds of azobenzene-containing gelators (AG1 and AG2) with different terminal groups were designed and synthesized. Both gelators could induce the nematic LC P0616A self-assemble into anisotropic phase-separated LC physical gels at low contents. Their phase-transition behavior, thermal stability, microstructure, and mechanical strength were systematically studied. Compared with AG2 in P0616A, the P0616A/AG1 gels showed better mechanical property. When the gelator content was above 3 wt %, the P0616A/AG1 gels possessed good self-supporting ability with a storage modulus more than 104 Pa. Thus, the photoresponsive electro-optical properties and structures of P0616A/AG1 gels were focused in detail. It was surprising that the electro-optical response speed of the P0616A/AG1 gels could be promoted upon UV irradiation. In particular, the decay time (τoff) was only about half when compared with the initial state, whereas the gels still exhibited good self-supporting ability; also the network of the LC physical gels had no change at macro- and microstructural levels. These exciting results would open a door for the application of this material in electro-optical devices.

20.
Zhongguo Zhong Yao Za Zhi ; 43(8): 1667-1674, 2018 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29751715

RESUMO

The study is to establish the two-dimension HPLC fingerprints of Dihuang (Rehmannia glutinosa), by HPLC-PDA and HPLC-ELSD methods. The separations were performed on Waters Atlantis®T3(4.6 mm× 250 mm,5 µm)and Welch Ultimate®Hilic-NH2(4.6 mm× 250 mm,5 µm)columns with the gradient elution of acetonitrile-0.01% phosphoric acid and acetonitrile-water, respectively. The chromatographic display wavelength for PDA detector was set at 203 nm. For HPLC-ELSD, the nebulizer was set as cooling mode, the drift tube temperature was set at 60 °C and the gas pressure was 35.0 psi. Based on similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine, 26 and 10 chromatographic peaks were determined as common components for HPLC-PDA and HPLC-ELSD fingerprints, respectively. Chemometrics analyses, such as similarity analysis; cluster analysis and principal component analysis, were performed on the common peak areas in two-dimension fingerprints for 41 batches of Dihuang from multiple sources. The results showed that the HPLC-PDA fingerprint could distinguish dried rehmannia root between different sources, and HPLC-ELSD fingerprint could differentiate dried rehmannia root from prepared rehmannia root. The two-dimension fingerprints were established with advantages of a good degree of separation, abundant chemical information and multi-components identified including two nucleosides (adenosine and uridine),four iridoid glycosides (catalpa alcohol,rehmaionoside D,rehmaionoside A and leonuride),two phenylethanoid glycosides (acteoside and cistanoside A) and nine sugars. The method is simple and practical, which could be used for the identification and quality assessment for Dihuang.


Assuntos
Medicamentos de Ervas Chinesas , Rehmannia , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa , Nucleosídeos , Controle de Qualidade
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