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1.
Phys Rev Lett ; 127(17): 172702, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34739274

RESUMO

The excited-state structure of atomic nuclei can modify nuclear processes in stellar environments. In this Letter, we study the influence of nuclear excitations on Urca cooling (repeated back-and-forth ß decay and electron capture in a pair of nuclear isotopes) in the crust and ocean of neutron stars. We provide for the first time an expression for Urca process neutrino luminosity which accounts for a thermal Boltzmann distribution of excited states in both members of an Urca pair. We use our new formula with state-of-the-art nuclear structure inputs to compute neutrino luminosities of candidate Urca cooling pairs. Our nuclear inputs consist of the latest experimental data supplemented with calculations using the projected shell model. We show that, in contrast to previous results that only consider the ground states of both nuclei in the pair, our calculated neutrino luminosities for different Urca pairs vary sensitively with the environment temperature and can be radically different from those obtained in the one-transition approximation. We find that nuclear excitations can lead to an enhancement in total Urca neutrino luminosities in the accreted neutron star crust by about 5 times as compared with the previous Urca results, which is expected to cause significant observational effects.

2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 41(6): 446-449, 2017 Nov 30.
Artigo em Chinês | MEDLINE | ID: mdl-29862708

RESUMO

The fundamental concept, measuring and calculating of Transcranial Doppler Diagnostic & Monitor System acoustic output power are introduced according to hydrophone scanning method and pulsing sequences principle. Then, the feasibility of the method is demonstrated. Finally, the detail calculating method of Transcranial Doppler Diagnostic & Monitor System has been derived.


Assuntos
Transdutores , Ultrassonografia Doppler Transcraniana/instrumentação , Acústica , Monitorização Fisiológica
3.
J Environ Sci (China) ; 45: 18-27, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27372115

RESUMO

Al substitution in goethite is common in soils, and has strong influence on the structure and physicochemical properties of goethite. In this research, a series of Al-doped goethites were synthesized, and characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR) and extended X-ray absorption fine structure (EXAFS) spectroscopy. The adsorption behavior of these samples towards PO4(3-) was also investigated. Characterization results demonstrated that increasing Al content in goethite led to a reduction in crystallinity, increase in specific surface area (SSA), and morphology change from needle-like to granular. Rietveld structure refinement revealed that the lattice parameter a remained almost constant and b slightly decreased, but c was significantly reduced, and the calculated crystal density increased. EXAFS analysis demonstrated that the Fe(Al)-O distance in the structure of the doped goethites was almost the same, but the Fe-Fe(Al) distance decreased with increasing Al content. Surface analysis showed that, with increasing Al content, the content of OH groups on the mineral surface increased. The adsorption of phosphate per unit mass of Al-doped goethite increased, while adsorption per unit area decreased owing to the decrease of the relative proportion of (110) facets in the total surface area of the minerals. The results of this research facilitate better understanding of the effect of Al substitution on the structure and properties of goethite and the cycling of phosphate in the environment.


Assuntos
Alumínio/química , Compostos de Ferro/química , Minerais/química , Fosfatos/química , Absorção Fisico-Química , Microscopia Eletrônica de Transmissão , Modelos Químicos , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
4.
Sci Rep ; 13(1): 15797, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737214

RESUMO

In the setting of the increasing density of exploration wells, and the decreasing scale and increasing difficulty of discovering Jurassic paleogeomorphology reservoirs, it is urgent to deepen the fine depiction of pre-Jurassic paleogeomorphology features and to analyze their controlling effect on reservoirs. Based on abundant logging data combined with indoor microscopic observation and experimental testing, the paper applies the theory of reservoir configuration analysis for the first time to the single-channel period division of the pre-Jurassic Meng-Shaan paleochannel which deposited with the braided channel sand bodies. Meanwhile, it reveals the controlling effect of hydrocarbon accumulation and the distribution characteristics of the Yan 101 reservoir as ' paleogeomorphology and sedimentary facies combination' to determine the type, 'migration channel' to determine the distributing range, and 'low-amplitude structure' to determine the trap in the study area, and also the reservoir accumulation modes in different channel ranges have established. In conclusion, the single-channel boundary of the Meng-Shaan paleochannel in different periods controls the path of oil and gas migration, thus controlling the distribution range and reservoir type of the Yan 10 reservoir. Moreover, depending on the production data we derived that it should prefer the composite trap reservoir of the Fuxian period and the Yan 102 period, as well as the structural reservoir on the periphery of the Yan 102 period single-channel for the further exploration of the Yan 10 paleogeomorphology reservoirs within the development range of the Meng-Shaan ancient river. In particular, the lithologic trap reservoirs within the Fuxian period channel and the Meng-Shaan main channel, such as the reservoirs of the 'Source' of the secondary channel type and the paleochannel type, which could as a replacement accumulation model for increasing reserves and production.

5.
Medicine (Baltimore) ; 99(17): e19842, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32332635

RESUMO

INTRODUCTION: Seborrheic alopecia (SA) has clinical manifestations, duration of disease, and priorities. In the current situation where there are many and complicated clinical treatments, Western medicine treatment can delay and control the development of the disease and promote hair regeneration. However, some patients may aggravate symptoms after taking the drug, and the condition is easy to repeat after stopping the drug. Acupuncture is an important method for non-surgical treatment of SA, and it has various methods, low side effects, high safety, and simple and economical. Therefore, we will use a clinical randomized controlled study to explore the effect of acupuncture on SA, and provide a new idea and reference for the treatment of this disease. METHODS/DESIGN: We will select 60 patients diagnosed with SA. They will be randomly divided into intervention group and control groups. The control group will be given conventional treatment measures. The intervention group will receive acupuncture. Efficacy will be evaluated by comparing the skin lesion score and dermatological quality of life index before and after treatment. DISCUSSION: This trial may provide evidence regarding the clinical effectiveness, safety, and cost-effectiveness of acupuncture for patients with SA. TRIAL REGISTRATION NUMBER: CTR2000030430.


Assuntos
Terapia por Acupuntura , Alopecia/etiologia , Alopecia/terapia , Dermatite Seborreica/complicações , Terapia por Acupuntura/economia , Adolescente , Adulto , Análise Custo-Benefício , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
6.
Bioinspir Biomim ; 14(6): 066005, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31434057

RESUMO

Birds are known for their extraordinary agility, maneuverability, flexibility and endurance during their flight, even under some adverse flying conditions. Bird wings have been the most inspirational element, attracting the attention of researchers to reveal the underlying physical mechanism of lift production as well as to apply the results into the artificial flying vehicles. This paper presents a systematic experimental investigation on a passive flow control of a NACA0012 airfoil using real feather flap which is installed on the suction or pressure surface. The focus of the present study is to determine the major role of a real feather flap in the aerodynamic performance of a NACA0012 airfoil at small attack angles (α). The feather flap width w and its installation position x in are varied from 0.27c to 0.8c and from 0.0 to 0.2c, respectively, where x in is measured from the leading edge of the airfoil, and c is the chord length of the airfoil. Detailed particle image velocimetry (PIV) measurements are conducted to understand the origin of the aerodynamic benefits introduced by the feather flap. The flap mounted on the suction side may have a positive impact only at large α, beyond the stall. On the other hand, when mounted on the pressure side, the feather flap is proved to be beneficial to improve the aerodynamic performance of the airfoil at small α (= -4° to 8°). The lift C L and lift-to-drag ratio C L /C D are enhanced by 186% and 72%, respectively, for w = 0.53c, x in = 0.2c at α = 2°. Time-averaged and instantaneous vorticities, time-averaged streamwise velocity, and lateral velocity around the flapped airfoil weaken, decrease and increase, respectively, compared with those around the plain airfoil, which are attributed to the increased C L and C L /C D .


Assuntos
Biomimética/instrumentação , Aves/fisiologia , Plumas/fisiologia , Animais , Fenômenos Biomecânicos , Simulação por Computador , Desenho de Equipamento , Voo Animal , Modelos Biológicos , Asas de Animais/fisiologia
7.
Medicine (Baltimore) ; 98(36): e17055, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31490403

RESUMO

BACKGROUND: Psoriasis is an immune-mediated polygenic hereditary skin disease quality of the patients' life because of the great trouble it causes to patients. Whereas, there is variability when we regard the selection of traditional Chinese medicine treatments in practice and most choices are made based on personal experience or preference of clinician. This study uses network meta-analysis to compare the effectiveness of different forms of TCM for psoriasis and assesses the evidence with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. METHODS: We will search for PubMed, Cochrane Library, AMED, EMbase, WorldSciNet; Nature, Science online and China Journal Full-text Database (CNKI), China Biomedical Literature CD-ROM Database (CBM), and related randomized controlled trials included in the China Resources Database. The time is limited from the construction of the library to April 2019. The quality of the included RCTs will be evaluated by the risk of bias (ROB) tool and the evidence will be evaluated by GRADE. STATA 13.0 and WinBUGS 1.4.3 through the GeMTC package will be used to perform a network meta-analysis to synthesize direct and indirect evidence. RESULTS: The results of this network meta-analysis (NMA) will be submitted to a peer-reviewed journal for publication. TRIAL REGISTRATION NUMBER: PROSPERO CRD42019137250.


Assuntos
Medicina Tradicional Chinesa , Psoríase/terapia , Teorema de Bayes , Humanos , Metanálise em Rede
8.
Steroids ; 89: 41-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25091151

RESUMO

An ultrasensitive and selective method is presented for the determination of diethylstilbestrol (DES) using time-resolved fluorescence immunoassay (TRFIA) based on double-codified gold nanoparticles (DC-AuNPs). In this system, the DC-AuNPs, that are gold nanoparticles (AuNPs) modified with anti-DES antibody and SH-dsDNA-biotin, was regarded as signal amplifier. A competitive immunoreaction was performed on polystyrene microtitration plates, where the DES compete with the immobilized DES-ovalbumin on polystyrene microtitration plates to bind to anti-DES antibodies on DC-AuNPs, and the europium(III)-labeled streptavidin was added to link to the SH-dsDNA-biotin as a tracer. Fluorescence signal was amplified via the AuNPs and the biotin-streptavidin double amplification systems. Under the optimized condition, DES can be quantified by TRFIA. The linear range and the limit of detection of DES were 1.0×10(-6)-10ngmL(-1) and 0.4fgmL(-1), respectively. This method was applied to determine DES in beef sample, with the recoveries ranging from 88% to 105%.


Assuntos
Dietilestilbestrol/isolamento & purificação , Análise de Alimentos/métodos , Ouro/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Animais , Anticorpos Anti-Idiotípicos/química , Anticorpos Anti-Idiotípicos/imunologia , Biotina/química , Bovinos , DNA/química , Dietilestilbestrol/toxicidade , Fluorescência , Produtos da Carne/intoxicação
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