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1.
Contemp Clin Trials ; 142: 107574, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763307

RESUMEN

BACKGROUND: Novel and scalable psychotherapies are urgently needed to address the depression and anxiety epidemic. Leveraging artificial intelligence (AI), a voice-based virtual coach named Lumen was developed to deliver problem solving treatment (PST). The first pilot trial showed promising changes in cognitive control measured by functional neuroimaging and improvements in depression and anxiety symptoms. METHODS: To further validate Lumen in a 3-arm randomized clinical trial, 200 participants with mild-to-moderate depression and/or anxiety will be randomly assigned in a 2:1:1 ratio to receive Lumen-coached PST, human-coached PST as active treatment comparison, or a waitlist control condition where participants can receive Lumen after the trial period. Participants will be assessed at baseline and 18 weeks. The primary aim is to confirm neural target engagement by testing whether compared with waitlist controls, Lumen participants will show significantly greater improvements from baseline to 18 weeks in the a priori neural target for cognitive control, right dorsal lateral prefrontal cortex engaged by the go/nogo task (primary superiority hypothesis). A secondary hypothesis will test whether compared with human-coached PST participants, Lumen participants will show equivalent improvements (i.e., noninferiority) in the same neural target from baseline to 18 weeks. The second aim is to examine (1) treatment effects on depression and anxiety symptoms, psychosocial functioning, and quality of life outcomes, and (2) relationships of neural target engagement to these patient-reported outcomes. CONCLUSIONS: This study offers potential to improve the reach and impact of psychotherapy, mitigating access, cost, and stigma barriers for people with depression and/or anxiety. CLINICALTRIALS: gov #: NCT05603923.


Asunto(s)
Ansiedad , Inteligencia Artificial , Depresión , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ansiedad/terapia , Consejo/métodos , Depresión/terapia , Neuroimagen Funcional/métodos , Corteza Prefrontal , Solución de Problemas , Distrés Psicológico , Psicoterapia/métodos , Calidad de Vida , Voz
2.
Materials (Basel) ; 15(8)2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35454559

RESUMEN

The 9-12% Cr ferritic-martensitic heat-resistant steel is the main candidate structural material for the Lead-cooled Faster Reactor. The lower Gibbs free energy change of Si oxide can promote the formation of a stable oxide layer, which can improve the corrosion resistance of the material. Therefore, it is of great significance to study the effect of silicon (Si) on the corrosion resistance of T91 steel in lead-bismuth eutectic (LBE). The corrosion resistance of T91 steel with Si contents of 0.5 wt.%, 1.3 wt.%, and 2.0 wt.%, both in dynamic and static LBE at 550 °C, was investigated. The microstructure was analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM), while the oxide films were characterized by electron probe microanalysis (EPMA). Results show that the addition of Si is conducive to improving the corrosion resistance of T91 steel in LBE. T91 steel with high Si content has a thinner and more stable oxide film. The change of Si content can change the contact angle between the steel and LBE, and the contact angle is the largest when the Si content is 1.3 wt.%. The Si-rich oxide layer is usually located in the inner oxide layer, which promotes the formation of a Cr oxide layer located in the internal oxidation zone (IOZ). Si will not enter the precipitated phase, but only change the ferrite content. The oxidation model of T91 steel containing Si in LBE was also proposed.

3.
Zhongguo Zhong Yao Za Zhi ; 45(2): 274-284, 2020 Jan.
Artículo en Chino | MEDLINE | ID: mdl-32237309

RESUMEN

In this paper, five representative Chinese herbal decoction pieces of Scutellariae Radix, Paeoniae Radix Alba, vinegar-processed Corydalis Rhizoma, Polygoni Multiflori Radix Praeparata and Lonicerae Japonicae Flos were selected to prepare the corresponding fine powder of pieces, extract powder, semi-extract powder and physical mixed powder. The physical properties of 20 kinds of powders, such as related parameters of particle size, density, stability and flowability, were evaluated comprehensively. The compression curves of powder porosity and tensile strength changing with pressure were plotted, and the Heckel equation and the Kawakita equation were used to describe the powder compression behavior. The results showed that compared with the fine powder of pieces, the compressibility of the semi-extract powder and the extract powder was significantly improved. Compared with the extract powder, the particle size and relative uniformity of the semi-extract powder were increased, indicating that the uniformity of the powder was improved. Besides, the semi-extract powder could reduce the hygroscopicity of the powder. Particularly, the semi-extract powder of Scutellariae Radix, Paeoniae Radix Alba and vinegar-processed Corydalis Rhizoma could maintain the porous structure of the tablet even under a high tableting pressure, which was beneficial to tablet disintegration. For some traditional Chinese medicines(such as Lonicerae Japonicae Flos), the semi-extract powder could reduce the viscosity, which avoided the sticking in the die compression. The semi-extract powder and the physical mixture powder prepared by the same Chinese herbal decoction pieces had similar physical properties and compression behaviors. Principal component analysis(PCA) was carried out on the 17 physical attributes and 5 compression parameters of the powder. It was found that the first principal component mainly reflected the differences among the material sources, while the second principal component could reflect the differences among fine powder of pieces, extract powder, semi-extract powder and physical mixed powder originating from the same Chinese herbal decoction pieces. In this paper, the mechanism of "unification of drugs and excipients" of Chinese medicine semi-extract powder was explained in terms of physical properties and compression behavior of powders, which provided reference for the formulation design and process development of Chinese medicine tablets.


Asunto(s)
Composición de Medicamentos , Medicamentos Herbarios Chinos , Excipientes , Medicina Tradicional China , Extractos Vegetales , Polvos , Comprimidos , Tecnología Farmacéutica
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(1): 55-7, 2011 Jan.
Artículo en Chino | MEDLINE | ID: mdl-21428055

RESUMEN

In the present paper, using UV CCD optical multi-channel analyzer, the solar ultraviolet radiation spectra under the conditions of cloud cover were measured, and the impact of clouds on the solar ultraviolet radiation spectra were studied mostly. The results of spectral analysis showed that the intensity of solar ultraviolet radiation spectra was weakened by the clouds. The solar ultraviolet radiation spectral intensity attenuation depended on the wavelength and decreased with decreasing wavelength. The greater the cloud cover, the stronger the attenuation, The solar ultraviolet radiation spectral intensity at wavelengths below 315 nm was affected relatively less by the cloud cover. These results have more important practical applications. When we use solar ultraviolet radiation spectrum to study the atmospheric composition, we should choose the spectral band that is less affected by the atmospheric environment.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 74(1): 168-73, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19553157

RESUMEN

Quantum chemistry calculations have been performed using Gaussian03 program to compute optimized geometry, harmonic vibrational frequency along with intensities in IR and Raman spectra and atomic charges at RHF/6-31+G*, B3LYP/6-31+G* and B3LYP/6-31++G* levels for 2-mercaptobenzothiazole (MBT, C(7)H(5)NS(2)) and 2-mercaptobenzoxazole (MBO, C(7)H(5)NOS) in the ground state. The scaled harmonic vibrational frequencies have been compared with experimental FT-IR and FT-Raman spectra. The results show that the scaled theoretical vibrational frequencies is very good agreement with the experimental values. A detailed interpretation of the infrared and Raman spectra of 2-mercaptobenzothiazole and 2-mercaptobenzoxazole was reported. Comparison of calculated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes.


Asunto(s)
Benzotiazoles/química , Benzoxazoles/química , Modelos Químicos , Compuestos de Sulfhidrilo/química , Carbono/química , Enlace de Hidrógeno , Modelos Biológicos , Conformación Molecular , Estructura Molecular , Teoría Cuántica , Espectroscopía Infrarroja por Transformada de Fourier , Vibración
6.
J Hazard Mater ; 165(1-3): 372-8, 2009 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-19019536

RESUMEN

Quantum chemical calculations are used to compute the heats of formation (HOFs) for 24 nitroester (NE) energetic compounds in which only 5 nitroester energetic compounds have the available experimental heats of formation. The heats of formation of the five compounds are calculated from isodesmic reactions by employing the hybrid density functional theory (DFT) (B3LYP, B3PW91, and B3P86) methods with 6-31G** and 6-311G** basis sets. It is demonstrated that B3PW91/6-31G** method can yield reliable HOFs, which has the mean absolute deviation of 1.1kcal/mol. The HOFs of other 19 nitroester energetic compounds are calculated by using B3PW91/6-31G** method. Through the analysis of the calculated result, it is found that the computed heat of formation decreases when the number of methylene (CH(2)) group increases for normal chain nitroester compounds. The further study shows that our results about gas-phase heats of formation of nitroester compounds are better than the results of Muthurajan et al. [H. Muthurajan, R. Sivabalan, M.B. Talawar, M. Anniyappan, S. Venugopalan, Prediction of heat of formation and related parameters of high energy materials, J. Hazard. Mater. A133 (2006) 30-45], and Byrd Edward and Rice Betsy [F.C. Byrd Edward, M. Rice Betsy, Improved prediction of heats of formation of energetic materials using quantum mechanical calculations, J. Phys. Chem. A 110 (2006) 1005-1013]. In addition, the condensed phase heat of formation of the nitroester compounds are computed through the same method of Byrd Edward and Rice Betsy.


Asunto(s)
Ésteres/química , Nitrocompuestos/química , Termodinámica , Modelos Moleculares
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