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1.
Anal Chem ; 96(23): 9379-9389, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38805056

RESUMO

Over the years, a number of state-of-the-art data analysis tools have been developed to provide a comprehensive analysis of data collected from gas chromatography-mass spectrometry (GC-MS). Unfortunately, the time shift problem remains unsolved in these tools. Here, we developed a novel comprehensive data analysis strategy for GC-MS-based untargeted metabolomics (AntDAS-GCMS) to perform total ion chromatogram peak detection, peak resolution, time shift correction, component registration, statistical analysis, and compound identification. Time shift correction was specifically optimized in this work. The information on mass spectra and elution profiles of compounds was used to search for inherent landmarks within analyzed samples to resolve the time shift problem across samples efficiently and accurately. The performance of our AntDAS-GCMS was comprehensively investigated by using four complex GC-MS data sets with various types of time shift problems. Meanwhile, AntDAS-GCMS was compared with advanced GC-MS data analysis tools and classic time shift correction methods. Results indicated that AntDAS-GCMS could achieve the best performance compared to the other methods.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Metabolômica , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metabolômica/métodos , Animais , Fatores de Tempo , Análise de Dados
2.
Anal Chem ; 95(2): 638-649, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36599407

RESUMO

Data-dependent acquisition (DDA) mode in ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) can provide massive amounts of MS1 and MS/MS information of compounds in untargeted metabolomics and can thus facilitate compound identification greatly. In this work, we developed a new platform called AntDAS-DDA for the automatic processing of UHPLC-HRMS data sets acquired under the DDA mode. Several algorithms, including extracted ion chromatogram extraction, feature extraction, MS/MS spectrum construction, fragment ion identification, and MS1 spectrum construction, were developed within the platform. The performance of AntDAS-DDA was investigated comprehensively with a mixture of standard and complex plant data sets. Results suggested that features in complex sample matrices can be extracted effectively, and the constructed MS1 and MS/MS spectra can benefit in compound identification greatly. The efficiency of compound identification can be improved by about 20%. AntDAS-DDA can take full advantage of MS/MS information in multiple sample analyses and provide more MS/MS spectra than single sample analysis. A comparison with advanced data analysis tools indicated that AntDAS-DDA may be used as an alternative for routine UHPLC-HRMS-based untargeted metabolomics. AntDAS-DDA is freely available at http://www.pmdb.org.cn/antdasdda.


Assuntos
Metabolômica , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Metabolômica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Íons , Análise de Dados
3.
J Gambl Stud ; 38(4): 1323-1335, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34855054

RESUMO

Previous research has demonstrated that individuals present increased risk taking at the end of a series of gambles, a phenomenon called the ending effect. By using a large online football gambling data, we attempted to replicate the ending effect and tested the existence of a different pattern of increased risk taking at the ending. The results showed that at the end of a series of football gambles, bettors would take more risks, and options with lower risk would be preferred. In games without the interference of local bettors, the ending effect was found to be stronger than that of games with local bettors. Overall, the results provide evidence for the bounded ending effect. Possible underlying mechanisms of the bounded ending effect are explored.


Assuntos
Futebol Americano , Jogo de Azar , Futebol , Humanos , Jogo de Azar/psicologia , Fatores de Risco
4.
EMBO Rep ; 20(9): e47892, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31318145

RESUMO

The conversion of skeletal muscle fiber from fast twitch to slow-twitch is important for sustained and tonic contractile events, maintenance of energy homeostasis, and the alleviation of fatigue. Skeletal muscle remodeling is effectively induced by endurance or aerobic exercise, which also generates several tricarboxylic acid (TCA) cycle intermediates, including succinate. However, whether succinate regulates muscle fiber-type transitions remains unclear. Here, we found that dietary succinate supplementation increased endurance exercise ability, myosin heavy chain I expression, aerobic enzyme activity, oxygen consumption, and mitochondrial biogenesis in mouse skeletal muscle. By contrast, succinate decreased lactate dehydrogenase activity, lactate production, and myosin heavy chain IIb expression. Further, by using pharmacological or genetic loss-of-function models generated by phospholipase Cß antagonists, SUNCR1 global knockout, or SUNCR1 gastrocnemius-specific knockdown, we found that the effects of succinate on skeletal muscle fiber-type remodeling are mediated by SUNCR1 and its downstream calcium/NFAT signaling pathway. In summary, our results demonstrate succinate induces transition of skeletal muscle fiber via SUNCR1 signaling pathway. These findings suggest the potential beneficial use of succinate-based compounds in both athletic and sedentary populations.


Assuntos
Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Ácido Succínico/farmacologia , Animais , Ciclo do Ácido Cítrico/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Contração Muscular/efeitos dos fármacos , Fadiga Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Cadeias Pesadas de Miosina/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
6.
Int J Psychol ; 53 Suppl 1: 21-26, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28295294

RESUMO

Inequalities between men and women are common and well-documented. Objective indexes show that men are better positioned than women in societal hierarchies-there is no single country in the world without a gender gap. In contrast, researchers have found that the women-are-wonderful effect-that women are evaluated more positively than men overall-is also common. Cross-cultural studies on gender equality reveal that the more gender egalitarian the society is, the less prevalent explicit gender stereotypes are. Yet, because self-reported gender stereotypes may differ from implicit attitudes towards each gender, we reanalysed data collected across 44 cultures, and (a) confirmed that societal gender egalitarianism reduces the women-are-wonderful effect when it is measured more implicitly (i.e. rating the personality of men and women presented in images) and (b) documented that the social perception of men benefits more from gender egalitarianism than that of women.


Assuntos
Comparação Transcultural , Identidade de Gênero , Fatores Socioeconômicos , Feminino , Humanos , Percepção Social , Inquéritos e Questionários
8.
Inorg Chem ; 55(2): 902-8, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26701372

RESUMO

A self-assembled cobalt molecular grid of a pyrazine-bridged bis-tridentate ligand (L(R)), where R = H (1), CH3 (2), and Br (3), was prepared and structurally characterized. Depending on the electronic effects of the substituents on the ligand, the redox of the metal center was systematically modulated, and the magnetic behavior from essentially high-spin Co(II) in 3 versus completely diamagnetic Co(III) in 1 to Co(II) spin-crossover in 2 can be achieved.

9.
Inorg Chem ; 55(11): 5476-84, 2016 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-27164298

RESUMO

Structural assembly and reversible transformation between a metallogrid Dy4 SMM (2) and its fragment Dy2 (1) were established in the different solvent media. The zero-field magnetization relaxation was slowed for dysprosium metallogrid (2) with relaxation barrier of Ueff = 61.3 K when compared to Dy2 (1). Both magnetic dilution and application of a moderate magnetic field suppress ground-state quantum tunneling of magnetization and result in an enhanced Ueff of 119.9 and 96.7 K for 2, respectively. Interestingly, the lanthanide metallogrid complex (2) exhibits magnetic hysteresis loop even up to 16 K at a given field sweep rate of 500 Oe/s.

10.
Nanotechnology ; 27(46): 465203, 2016 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-27749284

RESUMO

The nonlinear absorption and nonlinear refractive properties of ZrSe3 nanoflakes were studied with a 6.5 ns pulse laser at 532 nm. Open-aperture Z-scan curves reveal that ZrSe3 nanoflakes have a strong reverse saturable absorption property, and close-aperture Z-scan curves show that ZrSe3 dispersions possess a positive nonlinear refractive index caused by self-focusing. The nonlinear absorption coefficient, the nonlinear refraction coefficient, and the figures of merit (FOM) of ZrSe3 dispersed in water with linear transmittances of 0.86 at input energy of 18 µJ are 6.35 × 10-10 m W-1 15.73 × 10-17 m2 W-1, and 10.09 × 10-11 esu · cm respectively. In addition, nonlinear optical (NLO) performance of ZrSe3 nanoflakes depends on organic solvent dispersions. ZrSe3 nanoflakes in water dispersions have the largest FOM of 10.27 × 10-11 esu · cm, while the FOM in ethanol dispersions is 5.41 × 10-11 esu · cm at the same input energy of 26.5 µJ. The optical limiting threshold Fth of ZrSe3 nanosheet is 2.2 J cm-2 under picosecond laser pulse. The Results imply that ZrSe3 nanoflakes are an extraordinarily promising material for novel nanophotonic devices like optical limiters.

11.
Analyst ; 140(22): 7622-8, 2015 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-26421323

RESUMO

A novel fluorescent resonant energy transfer (FRET) biosensor was fabricated for the detection of hepatitis B virus (HBV) DNA using poly(ethylenimine) (PEI) modified upconversion nanoparticles (NH2-UCNPs) as energy donor and gold nanoparticles (Au NPs) as acceptor. The PEI modified upconversion nanoparticles were prepared directly with a simple one-pot hydrothermal method, which provides high quality amino-group functionalized UCNPs with uniform morphology and strong upconversion luminescence. Two single-stranded DNA strands, which were partially complementary to each other, were then conjugated with NH2-UCNPs and Au NPs. When DNA conjugated NH2-UCNPs and Au NPs are mixed together, the hybridization between complementary DNA sequences on UCNPs and Au NPs will lead to the quenching of the upconversion luminescence due to the FRET process. Meanwhile, upon the addition of target DNA, Au NPs will leave the surface of the UCNPs and the upconversion luminescence can be restored because of the formation of the more stable double-stranded DNA on the UCNPs. The sensor we fabricated here for target DNA detection shows good sensitivity and high selectivity, which has the potential for clinical applications in the analysis of HBV and other DNA sequences.


Assuntos
DNA Viral/análise , Ouro/química , Vírus da Hepatite B/isolamento & purificação , Hepatite B/virologia , Substâncias Luminescentes/química , Nanopartículas/química , Polietilenoimina/química , Sequência de Bases , Transferência Ressonante de Energia de Fluorescência/métodos , Hepatite B/diagnóstico , Humanos , Nanopartículas/ultraestrutura , Hibridização de Ácido Nucleico/métodos
12.
Int J Psychol ; 50(2): 150-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25066890

RESUMO

Social perception studies have revealed that smiling individuals are perceived more favourably on many communion dimensions in comparison to nonsmiling individuals. Research on gender differences in smiling habits showed that women smile more than men. In our study, we investigated this phenomena further and hypothesised that women perceive smiling individuals as more honest than men. An experiment conducted in seven countries (China, Germany, Mexico, Norway, Poland, Republic of South Africa and USA) revealed that gender may influence the perception of honesty in smiling individuals. We compared ratings of honesty made by male and female participants who viewed photos of smiling and nonsmiling people. While men and women did not differ on ratings of honesty in nonsmiling individuals, women assessed smiling individuals as more honest than men did. We discuss these results from a social norms perspective.


Assuntos
Características Culturais , Expressão Facial , Relações Interpessoais , Sorriso , Percepção Social , Adulto , China , Comparação Transcultural , Feminino , Alemanha , Humanos , Masculino , México , Pessoa de Meia-Idade , Noruega , Polônia , Fatores Sexuais , África do Sul , Estados Unidos
13.
Small ; 10(23): 4905-11, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25048818

RESUMO

Two new flexible visible-light photodetectors based on ZrS3 nanobelts films are fabricated on a polypropylene (PP) film and printing paper, respectively, by an adhesive-tape transfer method, and their light-induced electric properties are investigated in detail. The devices demonstrate a remarkable response to 405 to 780 nm light, a photocurrent that depends on the optical power and light wavelength, and an excellent photoswitching effect and stability. This implies that ZrS3 nanobelts are prospective candidates for high-performance nanoscale optoelectronic devices that may be practically applied in photodetection of visible to near infrared light. The facile fabrication method is extendable to flexible nanodevices with different nanostructures.

14.
Inorg Chem ; 53(24): 12671-3, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25407483

RESUMO

Field-induced slow magnetic relaxation was observed for air-stable mononuclear cobalt(II) compounds with pentagonal bipyramid geometry. These are the first examples of such behavior observed in the seven-coordinated mononuclear 3d metal compounds.

15.
Psychol Rep ; 114(1): 50-67, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24765709

RESUMO

Past research examining the effect of anger and sadness on decision making has associated anger with a relatively more heuristic decision-making approach. However, it is unclear whether angry and sad individuals differ while attending to decision-relevant information. An eye-tracking experiment (N=87) was conducted to examine the role of attention in links between emotion and decision making. Angry individuals looked more and earlier toward heuristic cues while making decisions, whereas sad individuals did not show such bias. Implications for designing persuasive messages and studying motivated visual processing were discussed.


Assuntos
Ira/fisiologia , Atenção/fisiologia , Tomada de Decisões/fisiologia , Adolescente , Sinais (Psicologia) , Emoções/fisiologia , Medições dos Movimentos Oculares , Movimentos Oculares/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1153-7, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25095397

RESUMO

The effects of assistant side-blown operating parameters on the behavior of plasma characteristics and plasma geometry were studied with the aid of high-speed camera in laser dressing of bronze-bonded diamond grinding wheel. The results showed that: high pressure argon plasma reduces swelling height, and as the pressure increases, argon blowing side of the plasma effect is more obvious. Plasma emission spectrum was studied on the grinding wheel radial maximum value with the change in argon gas pressure through the acquisition of plasma emission spectroscopy using spectrometer, and according to the Boltzmann slash and Stark broadening method, the maximal values of plasma electron temperature and electron density in the wheel radial were calculated. It was found that the plasma spectral line intensity first increased and then decreased as gas pressure reached the peak at 0. 2 MPa, Larger argon pressure can significantly reduce the temperature and density of plasmas. With optical 3D scanner the wheel surface topography before and after adding side-blown gas was compared. The results indicated that: the topography of grinding wheel with 0. 5 MPa side-blown argon is better than that without adding side-blown gas.

17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(5): 1571-1577, 2024 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-39479850

RESUMO

OBJECTIVE: To explore the effect of heterozygous deletion of histone methyltransferase Kmt2c gene on the hematological system of mice. METHODS: CRISPR/Cas9 technology was used to construct mice model of Kmt2c heterozygous deletion (Kmt2c+/-) and the changes of whole blood cell count in mice were continuously monitored by blood routine test. The clonal expansion ability of bone marrow cells was explored by colony formation assay in vitro and the proportion of primitive hematopoietic cells, including long-term hematopoietic stem cell (LT-HSC), short-term hematopoietic stem cell (ST-HSC), and multipotent progenitor cell in mutant mice was analyzed by flow cytometry. RESULTS: Kmt2c+/- mice model was successfully constructed, and the mRNA expression level of Kmt2c was 28% of that of C57BL/6J mice. The colony formation ability of bone marrow cells of Kmt2c+/- mice in vitro increased with the passage times, and the colony number in the fourth generation was significantly higher than that of control group (P <0.05). The proportions of LT-HSC and ST-HSC in the primitive hematopoietic cell population of Kmt2c+/- mice was 19.6%±3.3% and 28.9%±4.9%, respectively, which showed an increasing trend compared with 16.9%±2.6% and 18.9%±2.5% in control group, but the difference was not statistically significant (P >0.05). The white blood cell count of Kmt2c+/- mice gradually increased after 12 weeks of monitoring and reached (9.8±1.0)×109/L at the 14th week, which was significantly higher than (7.3±1.4)×109/L of control group (P < 0.05). CONCLUSION: The bone marrow cells of Kmt2c+/- mice have potential of clonal expansion.


Assuntos
Células da Medula Óssea , Células-Tronco Hematopoéticas , Camundongos Endogâmicos C57BL , Animais , Camundongos , Histona-Lisina N-Metiltransferase/genética , Heterozigoto , Genes Supressores de Tumor , Deleção de Genes , Sistema Hematopoético , Sistemas CRISPR-Cas
18.
J Chromatogr A ; 1716: 464653, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38232638

RESUMO

The comprehensive study of compound variations in released smoke during the combustion process is a great challenge in many scientific fields related to analytical chemistry like traditional Chinese medicine, environment analysis, food analysis, etc. In this work, we propose a new comprehensive strategy for efficiently and high-thoroughly characterizing compounds in the online released complex smokes: (i) A smoke capture device was designed for efficiently collecting chemical constituents to perform gas chromatography-mass spectrometry (GC-MS) based untargeted analysis. (ii) An advanced data analysis tool, AntDAS-GCMS, was used for automatically extracting compounds in the original acquired GC-MS data files. Additionally, a GC-MS data analysis guided instrumental parameter optimizing strategy was proposed for the optimization of parameters in the smoke capture device. The developed strategy was demonstrated by the study of compound variations in the smoke of traditional Chinese medicine, Artemisia argyi Levl. et Vant. The results indicated that more than 590 components showed significant differences among released smokes of various moxa velvet ratios. Finally, about 88 compounds were identified, of which phenolic compounds were the most abundant, followed by aromatics, alkenes, alcohols and furans. In conclusion, we may provide a novel approach to the studies of compounds in online released smoke.


Assuntos
Artemisia , Artemisia/química , Medicina Tradicional Chinesa , Fumaça , Cromatografia Gasosa-Espectrometria de Massas/métodos
19.
J Am Chem Soc ; 135(43): 16006-9, 2013 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-24131156

RESUMO

A series of end-to-end azido-bridged perovskite-type compounds [(CH3)nNH4-n][Mn(N3)3] (n = 1-4) were synthesized and characterized. Structural phase transitions indicating the general lattice flexibility were observed and confirmed by the crystal structures of different phases. These materials show cation-dependent magnetic ordering at up to 92 K and magnetic bistability near room temperature.


Assuntos
Azidas/química , Compostos de Cálcio/química , Cátions/química , Óxidos/química , Titânio/química , Azidas/síntese química , Hidrocarbonetos Aromáticos com Pontes , Compostos de Cálcio/síntese química , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Estabilidade de Medicamentos , Campos Magnéticos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Óxidos/síntese química , Temperatura
20.
J Am Chem Soc ; 135(36): 13302-5, 2013 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-23967875

RESUMO

Three trinuclear Mn2Mo molecules based on the orbitally degenerate [Mo(CN)7](4-) anion were prepared, one of which is the first single-molecule magnet (SMM) based on heptacyanomolybdate. The blocking temperature and the energy barrier (U = 40.5 cm(-1)) are records for a cyanide-based SMM. Wide hysteresis loops and sharp quantum tunneling steps were observed from single-crystal measurements.

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