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1.
Nucleic Acids Res ; 52(D1): D265-D272, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37855663

RESUMO

Riboswitches are regulatory elements found in the untranslated regions (UTRs) of certain mRNA molecules. They typically comprise two distinct domains: an aptamer domain that can bind to specific small molecules, and an expression platform that controls gene expression. Riboswitches work by undergoing a conformational change upon binding to their specific ligand, thus activating or repressing the genes downstream. This mechanism allows gene expression regulation in response to metabolites or small molecules. To systematically summarise riboswitch structures and their related ligand binding functions, we present Ribocentre-switch, a comprehensive database of riboswitches, including the information as follows: sequences, structures, functions, ligand binding pockets and biological applications. It encompasses 56 riboswitches and 26 orphan riboswitches from over 430 references, with a total of 89 591 sequences. It serves as a good resource for comparing different riboswitches and facilitating the identification of potential riboswitch candidates. Therefore, it may facilitate the understanding of RNA structural conformational changes in response to ligand signaling. The database is publicly available at https://riboswitch.ribocentre.org.


Assuntos
Bases de Dados de Ácidos Nucleicos , Riboswitch , Ligantes , Conformação de Ácido Nucleico , Sequências Reguladoras de Ácido Nucleico , Transdução de Sinais
2.
Langmuir ; 40(1): 348-361, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38154090

RESUMO

In this study, hollow and hierarchical CuO micro-nano cubes wrapped by reduced graphene oxide (H-CuO MNCs@rGO) were designed and successfully fabricated via a novel three-step wet-chemical method. Benefiting from its unique hollow and hierarchical micro-nano structures, H-CuO MNCs@rGO exhibited significantly enhanced electrochemical Na+ storage performance when utilized as anode material for sodium-ion batteries (SIBs). Specifically, H-CuO MNCs@rGO demonstrated a specific capacity of 380.9 mAh g-1 in the initial reversible cycle and a capacity retention of 218.9 mAh g-1 after 150 cycles at a current density of 300 mA g-1. Furthermore, through the dominant pseudocapacitive behavior, an optimized rate capability of 221.2 mAh g-1 at 800 mA g-1 can be obtained for H-CuO MNCs@rGO. The comprehensive Na+ storage properties of H-CuO MNCs@rGO obviously exceeded those of hollow CuO cubes (H-CuO MNCs) and bulk CuO anodes. Such enhanced Na+ storage performances of H-CuO MNCs@rGO can be attributed to its reasonable hollow and hierarchical micro-nano structures, which provide abundant redox active sites, shorten Na+ migration pathway, buffer volume expansion, and improve electronic/ionic conductivity during sodiation/desodiation process. Our strategy provides a facile and innovative approach for the design of CuO with rational micro-nano structure as a high-performance anode for SIBs, which would also be a guiding way for tailoring transition metal oxides in other scalable and functional applications.

3.
Anal Bioanal Chem ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38358531

RESUMO

α-Glucosidase (α-Glu) is implicated in the progression and pathogenesis of type II diabetes (T2D). In this study, we developed a rapid colorimetric technique using platinum nanoparticles stabilized by chitosan (Ch-PtNPs) to detect α-Glu activity and its inhibitor. The Ch-PtNPs facilitate the conversion of 3,3',5,5'-tetramethylbenzidine (TMB) into oxidized TMB (oxTMB) in the presence of dissolved O2. The catalytic hydrolysis of 2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G) by α-Glu produces ascorbic acid (AA), which reduces oxTMB to TMB, leading to the fading of the blue color. However, the presence of α-Glu inhibitors (AGIs) hinders the generation of AA, allowing Ch-PtNPs to re-oxidize colorless TMB back to blue oxTMB. This unique phenomenon enables the colorimetric detection of α-Glu activity and AGIs. The linear range for α-Glu was found to be 0.1-1.0 U mL-1 and the detection limit was 0.026 U mL-1. Additionally, the half-maximal inhibition value (IC50) for acarbose, an α-Glu inhibitor, was calculated to be 0.4769 mM. Excitingly, this sensing platform successfully detected α-Glu activity in human serum samples and effectively screened AGIs. These promising findings highlight the potential application of the proposed strategy in clinical diabetes diagnosis and drug discovery.

4.
Phys Rev Lett ; 130(15): 151902, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37115875

RESUMO

Parton saturation is one of the most intriguing phenomena in the high energy nuclear physics research frontier, especially in the upcoming era of the Electron-Ion Collider (EIC). The lepton-jet correlation in deep inelastic scattering provides us with a new gateway to the parton saturation at the EIC. In particular, we demonstrate that azimuthal angle anisotropies of the lepton-jet correlation are sensitive to the strength of the saturation momentum in the EIC kinematic region. In contrast to the predictions based on the collinear framework calculation, significant nuclear modification of the anisotropies is observed when we compare the saturation physics results in e+p and e+Au scatterings. By measuring these harmonic coefficients at the EIC, one can conduct quantitative analyses in different collisional systems and unveil compelling evidence for saturation effects.

5.
Bioprocess Biosyst Eng ; 46(9): 1351-1363, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37468580

RESUMO

Erythritol is a novelty 4-carbon sugar polyol and has great potential to be used as the precursor of some platform chemicals. The increasing cost of glucose poses researchers shifting insights to the cheaper biodiesel raw materials. Herein, we engineered a non-degradation, non-byproducts Yarrowia lipolytica for the erythritol production with high-titer from glycerol. Initially, the degradation and competition modules were blocked by URA3 counter-selection marker. Subsequently, a shortened biosynthetic pathway was explored to elevate its synthetic flux by multi-modules combination expression of functional genes. Furthermore, a screened glycerol transporter ScFPS1 was integrated into ERY6 genome to promote the glycerol uptake. The constructed strain ERY8 produced 176.66 g/L erythritol in the 5-L bioreactor with a yield and productivity of 0.631 g/g and 1.23 g/L/h, respectively, which achieved the highest fermentation production efficiency till date. This study proposed a novel multi-modules combination strategy for effectively engineering Y. lipolytica to produce erythritol using glycerol.


Assuntos
Glicerol , Yarrowia , Glicerol/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Eritritol , Engenharia Metabólica , Reatores Biológicos
6.
Sensors (Basel) ; 23(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36772229

RESUMO

Polymer creep can significantly reduce the safety and dependability of composite applications, restricting their development and use in additional fields. In this study, single-factor and multi-factor analysis techniques were employed to systematically explore the impacts of nickel powder and graphene on the resistive creep of sensing units. The creep model between the rate of resistance changes and the pressure was established, and the material ratio was optimized to obtain a high creep resistance. The results demonstrated that the creep resistance was best when the filling particle was 10 wt.% and the ratio of nickel powder to graphene was 4:21, which was approximately 60% and 45% lower than the filling alone and the composite filling before optimization, respectively; the R2 of the theoretical value of the resistance creep model and the experimental value of the creep before and after optimization was 0.9736 and 0.9812, indicating that the resistance creep model was highly accurate. Consequently, the addition of filler particles with acceptable proportions, varied shapes, and different characteristics to polymers can effectively reduce polymer creep and has significant potential for the manufacture of sensing units for tactile sensors.

7.
Phys Rev Lett ; 128(20): 202302, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35657879

RESUMO

With the tremendous accomplishments of RHIC and the LHC experiments and the advent of the future electron-ion collider on the horizon, the quest for compelling evidence of the color glass condensate (CGC) has become one of the most aspiring goals in the high energy quantum chromodynamics research. Pursuing this question requires developing the precision test of the CGC formalism. By systematically implementing the threshold resummation, we significantly improve the stability of the next-to-leading-order calculation in CGC for forward rapidity hadron productions in pp and pA collisions, especially in the high p_{T} region, and obtain reliable descriptions of all existing data measured at RHIC and the LHC across all p_{T} regions. Consequently, this technique can pave the way for the precision studies of the CGC next-to-leading-order predictions by confronting them with a large amount of precise data.

8.
J Card Surg ; 37(4): 1083-1086, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35102592

RESUMO

Cardiovascular syphilis presented with concomitant aortic regurgitation (AR) and left coronary ostial stenosis is rare, usually treated with on-pump aortic valve replacement and coronary artery bypass graft. We report a critical case of AR and left coronary ostial stenosis due to cardiovascular syphilis treated with emergent salvage transcatheter aortic valve replacement and percutaneous coronary intervention.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Sífilis Cardiovascular , Substituição da Valva Aórtica Transcateter , Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/complicações , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/cirurgia , Humanos , Sífilis Cardiovascular/complicações , Sífilis Cardiovascular/cirurgia , Resultado do Tratamento
9.
J Environ Manage ; 323: 116170, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36115243

RESUMO

Taking variations in PM2.5 as indicators for assessing the performance of authority in air quality management will probably lead to misjudgment, as PM2.5 concentration is affected not only by anthropogenic emissions but also by uncontrollable circumstances. To solve this problem, we proposed a decomposition method to attribute the variations in PM2.5 to the contributions of meteorological conditions, cross-regional transports of pollutants, secondary aerosols, and local emissions. This method estimated the relationship between PM2.5 concentration and the various influencing factors using a semi-parametric generalized additive model. A case study was conducted in Shenyang, a heavily polluted city in northeast China, based on up to 595,000 hourly data samples from 2014 to 2017. The decomposition results indicated that the average PM2.5 in 2017 decreased by 39.80% compared with 2014, far exceeding the government's target of 15%, but only 11.79% of the decrease was benefited from the control of local emissions. The severe pollution event that occurred in November 2015 was induced by the combination of massive emissions from heating and meteorological conditions conducive to pollutant accumulation. Furthermore, the approach we proposed can be extended to any location that has monitoring data on air pollutant concentrations and meteorological conditions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental/métodos , Material Particulado/análise , Estações do Ano
10.
Fam Process ; 61(4): 1749-1766, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34939189

RESUMO

The present study explored the role of parenting styles as mediating mechanisms in the link between marital conflict and Chinese children's internalizing problems. Participants were N = 1269 families (mothers, fathers, and children) from Shanghai, P. R. China. Multisource assessments were employed at three time points. Mothers and fathers reported their marital conflict and parenting styles (authoritative, authoritarian) and teachers and children reported on children's internalizing problems. Results from the Actor-Partner Interdependence Model (APIM) showed significant actor and partner effects for associations between marital conflict and parenting styles. After controlling for internalizing problems at Time 1, only maternal authoritarian parenting continued to mediate the relations between mothers' reported marital conflict and change in children's internalizing problems over time. This research provides valuable information about how important aspects of parenting influence the relations between marital conflict and internalizing problems among Chinese children.


Assuntos
População do Leste Asiático , Mães , Criança , Feminino , Humanos , China
11.
Opt Express ; 29(2): 2402-2410, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726436

RESUMO

This work reports the real-time observation of the thermo-optical dynamics in silica microsphere resonators based on the dispersive time stretch technique. In general, the thermo-optical dynamics of silica microsphere resonators, including the thermal refraction and thermal expansion, can be characterized by the resonance wavelength shift, whose duration is at the millisecond timescale. However, this fast wavelength shift process cannot be directly captured by conventional spectroscopy, and only its transmission feature can be characterized by a fast-scanning laser and an intensity detector. With the advance of the time-stretch spectroscopy, whose temporal resolution is up to tens of nanoseconds, the thermo-optical dynamics can be observed in a more straight-forward way, by utilizing the pump-probe technology and mapping the resonance wavelength to the time domain. Here, the thermo-optical dynamics are explored as a function of the power and the scanning rate of the pump laser. Theoretical simulations reproduce the experimental results, revealing that the thermo-optical dynamics of silica microsphere resonators is dominated by the fast thermo-optical effect and the slow heat dissipation process to the surroundings, which leads to gradual regression of the resonance wavelength. This work provides an alternative solution for studying the thermo-optical dynamics in whispering gallery mode microresonators, which would be crucial for future applications of microresonator photonic systems.

12.
Phys Rev Lett ; 126(14): 142001, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891436

RESUMO

We investigate the effect of soft gluon radiations on the azimuthal angle correlation between the total and relative momenta of two jets in inclusive and exclusive dijet processes. We show that the final state effect induces a sizable cos(2ϕ) anisotropy due to gluon emissions near the jet cones. The phenomenological consequences of this observation are discussed for various collider experiments, including diffractive processes in ultraperipheral pA and AA collisions, inclusive and diffractive dijet production at the EIC, and inclusive dijet in pp and AA collisions at the LHC.

13.
J Res Adolesc ; 31(3): 748-763, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34448308

RESUMO

This mixed-methods study explored adolescents' (n = 682) feelings of social connection in the time of the COVID-19 pandemic and examined potential risk (fear of missing out, problematic smartphone use) and protective (parent/peer attachment, smartphone use) factors to social disconnection. Data were collected from two schools in Canada using an online survey with questionnaires and open-ended questions. Three themes regarding adolescents' feelings of social connection during the pandemic were identified through thematic content analysis: (1) feeling socially connected, (2) feeling socially disconnected, and (3) feeling socially indifferent. Moreover, regression analysis identified secure peer attachments as a protective factor against social disconnection in the time of the COVID-19 pandemic, while fear of missing out was identified as an independent risk factor.


Assuntos
COVID-19 , Smartphone , Adolescente , Medo , Humanos , Pandemias , SARS-CoV-2
14.
Phys Rev Lett ; 125(23): 232301, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33337192

RESUMO

We investigate the azimuthal angular correlation between the lepton transverse momentum P_{⊥} and the impact parameter b_{⊥} in noncentral heavy-ion collisions, where the leptons are produced through two-photon scattering. Among the Fourier harmonic coefficients, a significant v_{4} asymmetry is found for the typical kinematics at RHIC and LHC with a mild dependence on the P_{⊥}, whereas v_{2} is power suppressed by the lepton mass over P_{⊥}. This unique prediction, if confirmed from the experiments, shall provide crucial information on the production mechanism for the dilepton in two-photon processes.

15.
Ecotoxicol Environ Saf ; 194: 110454, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32171962

RESUMO

The wide application of silver nanoparticles (AgNPs) has inevitably led to their release into the natural aquatic environment. Natural organic matter (NOM) is ubiquitous and would influence the fate and effects of these nanoparticles in such aquatic environments. Here we demonstrate that NOM plays an important role in the bioaccumulation kinetics and tissue distribution of AgNPs in zebrafish. In the presence of humic acid and fulvic acid, the uptake rates of AgNPs decreased while the depuration rates of AgNPs increased. As a result, the bioconcentration factor (BCF) of AgNPs in the entire body of the zebrafish was reduced. AgNPs were mainly taken up by the zebrafish via oral ingestion and were greatly accumulated in the liver, intestine and gill. In the intestine, NOM effectively inhibited the AgNPs from penetrating the cell membranes into internal tissues and also suppressed the disintegration and dissolution of AgNPs in gastrointestinal fluid, thereby decreasing the absorption of Ag by zebrafish. This research underlines the significance of incorporating the effects of NOM into predictive models for accurately assessing the toxicity and ecological risks of nanoparticles in natural aquatic environments.


Assuntos
Nanopartículas Metálicas/análise , Prata/metabolismo , Poluentes Químicos da Água/metabolismo , Peixe-Zebra/metabolismo , Animais , Benzopiranos , Bioacumulação , Substâncias Húmicas/análise , Cinética , Distribuição Tecidual
16.
Phys Rev Lett ; 122(13): 132301, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31012634

RESUMO

We investigate the P_{T}-broadening effects in dilepton production through photon-photon scattering in heavy ion collisions. The QED multiple interaction effect with the medium is found to be consistent with the recent observation of a low transverse momentum lepton pair from the ATLAS Collaboration at the LHC. We further comment on the magnetic broadening effect and point out a number of ways to disentangle these two mechanisms. In particular, the rapidity dependence of the P_{T}-broadening effect provides a unique probe to the magnetic effect.

17.
Phys Rev Lett ; 122(17): 172302, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31107089

RESUMO

Using the dilute-dense factorization in the color glass condensate framework, we investigate the azimuthal angular correlation between a heavy quarkonium and a charged light hadron in proton-nucleus collisions. We extract the second harmonic v_{2}, commonly known as the elliptic flow, with the light hadron as the reference. This particular azimuthal angular correlation between a heavy meson and a light hadron was first measured at the LHC recently. The experimental results indicate that the elliptic flows for heavy flavor mesons (J/ψ and D^{0}) are almost as large as those for light hadrons. Our calculation demonstrates that this result can be naturally interpreted as an initial state effect due to the interaction between the incoming partons from the proton and the dense gluons inside the target nucleus. Since the heavy quarkonium v_{2} exhibits a weak mass dependence according to our calculation, we predict that the heavy quarkonium ϒ should have a similar elliptic flow as compared to that of the J/ψ, which can be tested in future measurements.

18.
Phys Rev Lett ; 116(20): 202301, 2016 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-27258865

RESUMO

We investigate the close connection between the quantum phase space Wigner distribution of small-x gluons and the color dipole scattering amplitude, and we propose studying it experimentally in the hard diffractive dijet production at the planned electron-ion collider. The angular correlation between the nucleon recoiled momentum and the dijet transverse momentum probes the nontrivial correlation in the phase space Wigner distribution. This experimental study not only provides us with three-dimensional tomographic pictures of gluons inside high energy protons-it gives a unique and interesting signal for the small-x dynamics with QCD evolution effects.

19.
Phys Rev Lett ; 112(1): 012302, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24483891

RESUMO

We present results from the first next-to-leading-order (NLO) numerical analysis of forward hadron production in pA and dA collisions in the small-x saturation formalism. Using parton distributions and fragmentation functions at NLO, as well as the dipole amplitude from the solution to the Balitsky-Kovchegov equation with running coupling, together with the NLO corrections to the hard coefficients, we obtain a good description of the available RHIC data in dAu collisions. In the large p⊥ region beyond the saturation scale, we find that the NLO correction becomes dominant and negative, which indicates that other physics beyond NLO becomes important and should also be taken into account. Furthermore, we make predictions for forward hadron production in pPb collisions at the LHC. This analysis not only incorporates the important NLO corrections for all partonic channels, but also reduces the renormalization scale dependence and helps to significantly reduce the theoretical uncertainties. It therefore provides a precise test of saturation physics beyond the leading logarithmic approximation.

20.
Environ Sci Pollut Res Int ; 31(26): 38367-38384, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38805134

RESUMO

This study adopts a new approach to reassess the factors influencing urban energy intensity in China. Initially, the factors impacting energy intensity are classified into controllable and uncontrollable categories. Subsequently, employing a single-factor multi-stage method combined with the Adaboost method, 289 Chinese cities are categorized based on uncontrollable factors to eliminate the influence of inherent differences on energy intensity. Finally, panel data regression analyses are conducted using data from 289 Chinese cities between 2005 and 2016, individually for each city type, to evaluate the extent to which controllable factors contribute to energy intensity. The findings indicate that (1) heightened energy prices, an increased share of electricity consumption, and a greater proportion of centralized heating significantly influence the reduction of energy intensity across all city types; (2) to optimize energy consumption, each city type should adopt specific strategies. For instance, cities located in resource-rich heating regions with low economic outputs can reduce their energy intensity by increasing electricity consumption, while cities with high economic outputs can decrease their energy intensity by increasing natural gas consumption. The findings of this study carry substantial implications for the Chinese government in shaping targeted energy policies tailored to different city types.


Assuntos
Cidades , China , Eletricidade , Fontes Geradoras de Energia , Gás Natural
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