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1.
Materials (Basel) ; 17(7)2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38612190

RESUMEN

In the quest to enhance the mechanical properties of CuP alloys, particularly focusing on the Cu3P phase, this study introduces a comprehensive investigation into the effects of various alloying elements on the alloy's performance. In this paper, the first principle of density universal function theory and the projection-enhanced wave method under VASP 5.4.4 software are used to recalculate the lattice constants, evaluate the lattice stability, and explore the mechanical properties of selected doped elements such as In, Si, V, Al, Bi, Nb, Sc, Ta, Ti, Y and Zr, including shear, stiffness, compression, and plasticity. The investigation reveals that strategic doping with In and Si significantly enhances shear resistance and stiffness, while V addition notably augments compressive resistance. Furthermore, incorporating Al, Bi, Nb, Sc, Ta, Ti, V, Y, and Zr has substantially improved plasticity, indicating a broad spectrum of mechanical enhancement through precise alloying. Crucially, the validation of our computational models is demonstrated through hardness experiments on Si and Sn-doped specimens, corroborating the theoretical predictions. Additionally, a meticulous analysis of the states' density further confirms our computational approach's accuracy and reliability. This study highlights the potential of targeted alloying to tailor the mechanical properties of Cu3P alloys and establishes a robust theoretical framework for predicting the effects of doping in metallic alloys. The findings presented herein offer valuable insights and a novel perspective on material design and optimization, marking a significant stride toward developing advanced materials with customized mechanical properties.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38083157

RESUMEN

In patients with retinal degenerative illnesses such as retinitis pigmentosa and age-related macular degeneration, retinal prosthesis shows the potential to restore partial vision. The natural stimuli are the aperiodic events distributed across a short time span. However, most studies commonly used periodic stimulation. Even though some in vitro studies explored the effect of aperiodic retinal stimulation on the retina ganglion cells' membrane potential, it still needs to understand how the aperiodic electrical stimulation on the retina affects the response in visual cortex. This study investigated how aperiodic retinal stimulation affects the electrically evoked cortical response compared with periodic stimulation in Sprague Dawley (SD) rats. We found that the aperiodic retinal stimulation evoked a significantly higher spike rate than the periodic pattern, especially at high frequencies (10 and 20 Hz). The spike rates showed a more significant difference between the periodic and 10% noise stimulation (P = 0.0013 at 20 Hz, two-tailed paired t-test) at 20 Hz stimulation. Regarding the temporal precision of responses, the responses to aperiodic stimulation showed higher temporal precision compared to periodic stimulation. The response to some stimulation pulse numbers under 10 and 20 Hz 50% noise and Poisson pattern stimulation was higher than the response to the first pulse. However, at the same frequency, the response to some stimulation pulse numbers under periodic stimulation was lower than the response to the first pulse. These findings raised a possible way to increase the response level and the temporal precision of the electrically evoked response.Clinical Relevance- This suggests that using aperiodic stimulation in retinal prostheses can increase electrically evoked response levels and temporal precision.


Asunto(s)
Retina , Corteza Visual , Humanos , Ratas , Animales , Ratas Sprague-Dawley , Retina/fisiología , Células Ganglionares de la Retina/fisiología , Corteza Visual/fisiología , Estimulación Eléctrica
3.
Environ Sci Pollut Res Int ; 30(41): 94721-94739, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37540419

RESUMEN

Provinces (cities and districts) with identifiable boundaries are under intense pressure to reduce emissions as a fundamental unit and research object of carbon peaking and carbon-neutrality goals. Due to the significant variability of regional development, achieving equilibrium between carbon emissions and carbon absorption is challenging, contributing to the difficulty of developing carbon emission reduction and relevant green strategic initiatives in China. Therefore, this paper explored the spatial effect of carbon balance with carbon pressure as the starting point. First, this paper defined the "carbon pressure index" (CPI) of 30 provinces (cities and districts) in China from 2000 to 2019. Second, this paper validated the CPI agglomeration evolutionary characteristics in global and local aspects based on the Moran's index. Third, this paper identified and decomposed the spatial heterogeneity of CPI using the kernel density estimation method and the Theil index, then extracted typical cities to analyze the specific causes. Finally, this paper classified the seven regions in China into four types according to a comprehensive analysis of CPI. The results indicated that China's ecological carbon cycle system was in a serious "carbon overload" state. Thirty provinces (cities and districts) showed significant spatial agglomeration characteristics. The spatial gap of CPI was gradually decreasing nationwide, and the intra-regional differences were the leading cause of CPI levels in China. This can provide policy basis for the improvement of China's balanced development system of regional carbon emission reduction.


Asunto(s)
Ciclo del Carbono , Ecosistema , China , Ciudades , Carbono , Desarrollo Económico , Dióxido de Carbono
4.
Food Chem X ; 18: 100706, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37215199

RESUMEN

Even though Cimicifuga sp. is widely used in functional foods around the world, the content and structure of its oligosaccharides remain unclear. Here, we isolated a mixture of oligosaccharides from Cimicifuga heracleifolia Kom. rhizomes with a yield of 9.5% w/w. Twenty-six oligosaccharide monomers from the mixture were purified using optimized SEC and HILIC techniques. The oligosaccharides were identified as belonging to two groups by using HPAEC-PAD, MALDI-TOF-MS, NMR and GC-MS methylation analyses. One group belongs to sucrose and inulin type fructo-oligosaccharides (FOS) {ß-d-Fruf-(2 â†’ 1)-[ß-d-Fruf-(2 ↔ 1)]n=1-12-α-d-Glcp} with a 3-14 degree of polymerization (DP). Oligosaccharides in the other group belong to the inulo-n-ose type FOS {ß-d-Fruf-(2 â†’ 1)-[ß-d-Fruf-(2 â†’ 1)]m=0-12-ß-d-Frup} with a DP of 2-14. This appears to be the first time that these oligosaccharides have been purified from Cimicifuga heracleifolia Kom., thus providing useful information concerning the utilization of Cimicifuga heracleifolia Kom. in functional foods.

5.
Biomed Pharmacother ; 160: 114400, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36805186

RESUMEN

Isoniazid (INH) is a highly effective single and/or combined first-line anti-tuberculosis (anti-TB) therapy drug, and the hepatotoxicity greatly limits its clinical application. INH-induced liver injury (INH-DILI) is a typical immune-mediated idiosyncratic drug-induced liver injury. Existing mechanisms including genetic variations in drug metabolism and immune responses cannot fully explain the differences in susceptibility and sensitivity to INH-DILI, suggesting that other factors may be involved. Accumulating evidence indicates that the development and severity of immune-mediated liver injury is related to gut microbiota. In this study, INH exposure caused liver damage, immune disregulation and microbiota profile alteration. Depletion of gut microbiota ameliorated INH-DILI, and improved INH-DILI-associated immune disorder and inflammatory response. Moreover, hepatotoxicity of INH was ameliorated by fecal microbiota transplantation (FMT) from INH-treated mice. Notably, Bifidobacterium abundance was significantly associated with transaminase levels. In conclusion, our results suggested that the effect of gut microbiota on INH-DILI was related to immunity, and the difference in INH-DILI sensitivity was related to the structure of gut microbiota. Changes in the structure of gut microbiota by continuous exposure of INH resulted in the tolerance to liver injury, and probiotics such as Bifidobacterium might play an important role in INH-DILI and its "adaptation" phenomenon. This work provides novel evidence for elucidating the underlying mechanism of difference in individual's response to INH-DILI and potential approach for intervening anti-TB drug liver injury by modulating gut microbiota.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Enfermedad Hepática Inducida por Sustancias y Drogas , Microbioma Gastrointestinal , Ratones , Animales , Isoniazida/toxicidad , Antituberculosos/toxicidad , Hígado
6.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(6): 648-654, 2022 Nov 30.
Artículo en Chino | MEDLINE | ID: mdl-36597393

RESUMEN

The current status of cardiopulmonary resuscitation in China were introduced. The function and working principle of cardiopulmonary resuscitation equipment were described. The research status of cardiopulmonary resuscitation equipment was summarized. The main problem existing in cardiopulmonary resuscitation equipment were analyzed. Finally, according to the main technical direction involved in the conception, the existing technologies were reviewed from four aspects: path planning, human-computer interaction, automatic defibrillation and intelligent compression.


Asunto(s)
Reanimación Cardiopulmonar , Humanos , China
7.
Artículo en Inglés | MEDLINE | ID: mdl-34152987

RESUMEN

Retinal prosthesis can restore partial vision in patients with retinal degenerative diseases such as retinitis pigmentosa and age-related macular degeneration. Epiretinal prosthesis is one of three therapeutic approaches, which received regulatory approval several years ago. The thresholds of an epiretinal stimulation is partly determined by the size of the physical gap between the electrode and the retina after implantation. Precise positioning of epiretinal stimulating electrode array is still a challenging task. In this study, we demonstrate an approach to positioning epiretinal prostheses for an optimal response at the cortical output by monitoring both the impedance at the electrode-retina interface and the evoked-potential at the cortical level. We implanted a single-channel electrode on the epiretinal surface in adult rats, acutely, guided by both the impedance at the electrode-retina interface and by electrically evoked potentials (EEPs) in the visual cortex during retinal stimulation. We observe that impedance monotonously increases with decreasing electrode-retina distance, but that the strongest cortical responses were achieved at intermediate impedance levels. When the electrode penetrates the retina, the impedance keeps increasing. The effect of stimulation on the retina changes from epiretinal paradigm to intra-retinal paradigm and a decrease in cortical activation is observed. It is found that high impedance is not always favorable to elicit best cortical responses. Histopathological results showed that the electrode was placed at the intra-retinal space at high impedance value. These results show that monitoring impedance at the electrode-retina interface is necessary but not sufficient in obtaining strong evoked-potentials at the cortical level. Monitoring the cortical EEPs together with the impedance can improve the safety of implantation as well as efficacy of stimulation in the next generation of retinal implants.


Asunto(s)
Retina , Prótesis Visuales , Animales , Impedancia Eléctrica , Estimulación Eléctrica , Electrodos , Electrodos Implantados , Potenciales Evocados Visuales , Humanos , Implantación de Prótesis , Ratas
8.
Interdiscip Sci ; 13(1): 128-139, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33595803

RESUMEN

Kochia scoparia has high medicinal and economic value. However, with similar morphological features, adulterants and some closely related species of K. scoparia are increasingly sold in the medicinal markets, leading to potential safety risks. In this study, 128 internal transcribed spacer 2 (ITS2) sequences were collected to distinguish K. scoparia from its closely related species and adulterants. Then, sequence alignment, sequence characteristics analysis, and genetic distance calculations were performed using MEGA 6.06 software, and the phylogenetic trees were reconstructed using both MEGA 6.06 and IQ-Tree software. Finally, the secondary structure of ITS2 was modeled using the prediction tool in the ITS2 database. The results showed that ITS2 sequences of K. scoparia ranged in length from 226 to 227 bp, with a mean GC content of 55.3%. The maximum intraspecific distance was zero, while the minimum interspecific distance from closely related species and adulterants was 0.009 and 0.242, respectively. Kochia scoparia formed an independent clade in the phylogenetic trees, and its secondary structure exhibited enough variation to be separated from that of other species. In summary, ITS2 can be used as a mini-barcode for distinguishing K. scoparia from closely related species and adulterants. Its phylogenetic trees could illustrate the evolutionary process of K. scoparia in the Camphorosmeae. The phylogenetic results using ITS2 barcode further supported the internationally recognized revised classifications of Kochia and Bassia genera as a combined Bassia genus, together with the establishment of new genera Grubovia and Sedobassia, which we suggest is accepted by the Flora of China. Graphical abstract .


Asunto(s)
Bassia scoparia , Filogenia , Plantas Medicinales , Bassia scoparia/genética , China , Código de Barras del ADN Taxonómico , ADN de Plantas , ADN Espaciador Ribosómico
9.
RSC Adv ; 10(19): 11535-11542, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35495350

RESUMEN

We report a facile method for preparation of polystyrene (PS) particles with spherical, raspberry-like, and hollow flower-like structures by single-step non-surfactant self-templating polymerization of styrene in ethanol-water mixtures. PS particles with diverse morphologies could be easily obtained by simply adjusting the volume ratios of the styrene/water/ethanol mixture and initiator-ethanol-water mixture. By decreasing this ratio, the particles with spherical, raspberry-like, and hollow flower-like structures were obtained in sequence. The wettability of the coatings changing from hydrophilicity to hydrophobicity was easily tuned by the PS particles with different roughnesses. A competitive mechanism of interfacial polymerization and exudation was proposed to interpret the formation of PS particles with diverse morphologies.

10.
Biomed Pharmacother ; 97: 423-428, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29091892

RESUMEN

The pathological characteristics of atherosclerosis (AS) include lipid accumulation, fibrosis formation and atherosclerotic plaque produced in artery intima, which leads to vascular sclerosis, lumen stenosis and irritates the ischemic changes of corresponding organs. Endothelial dysfunction was closely associated with AS. Nitric oxide (NO) is a multifunctional signaling molecule involved in the maintenance of metabolic and cardiovascular homeostasis. NO is also a potent endogenous vasodilator and enters for the key processes that suppresses the formation vascular lesion even AS. NO bioavailability indicates the production and utilization of endothelial NO in organisms, its decrease is related to oxidative stress, lipid infiltration, the expressions of some inflammatory factors and the alteration of vascular tone, which plays an important role in endothelial dysfunction. The enhancement of arginase activity and the increase in asymmetric dimethylarginine and hyperhomocysteinemia levels all contribute to AS by intervening NO bioavailability in human beings. Diabetes mellitus, obesity, chronic kidney disease and smoking, etc., also participate in AS by influencing NO bioavailability and NO level. Here, we reviewed the relationship between NO bioavailability and AS according the newest literatures.


Asunto(s)
Aterosclerosis/metabolismo , Endotelio Vascular/metabolismo , Óxido Nítrico/metabolismo , Animales , Arginina/análogos & derivados , Arginina/metabolismo , Aterosclerosis/epidemiología , Disponibilidad Biológica , Enfermedades Cardiovasculares/metabolismo , Humanos , Obesidad/epidemiología , Obesidad/metabolismo , Estrés Oxidativo/fisiología , Fumar/efectos adversos , Fumar/epidemiología , Fumar/metabolismo , Vasodilatación/fisiología
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