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1.
J Colloid Interface Sci ; 668: 525-539, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38691962

RESUMEN

Economical oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) bifunctional catalysts with high activity aimed at replacing precious metal catalysts for rechargeable zinc-air batteries (ZABs) must be developed. In this study, a multiple hierarchical-structural material is developed using a facile dielectric barrier discharge (DBD) plasma surface treatment, solvothermal reaction, and high-temperature carbonization strategy. This strategy allows for the construction of nanosheets using nitrogen-doped carbon (NC) material-encapsulated ternary CoNiFe alloy nanoparticles (NPs) on a network of NC nanotubes (NCNTs), denoted as CoNiFe-NC@p-NCNTs. Precisely, the presence of abundant CoNiFe alloy NPs and the formation of M-N-C active sites created by transition metals (cobalt, nickel, and iron) coupled with NC can provide superior OER/ORR bifunctional properties. Moreover, the prepared NC layers with a multilevel pore structure contribute to a larger specific surface area, exposing numerous active sites and enhancing the uniformity of electron and mass movement. The CoNiFe0.08-NC@p-NCNTs show remarkable dual functionality for electrochemical oxygen reactions (ORR half-wave potential of 0.811 V, limiting current density of 5.73 mA cm-2 measured with a rotating disk electrode at a rotation speed of 1600 rpm, and OER overpotential of 351 mV at 10 mA cm-2), which demonstrates similar ORR performance to 20 wt% Pt/C and better OER performance than the commercial RuO2. A liquid ZAB prepared using the proposed material has excellent bifunctionality with an open-circuit voltage of 1.450 V and long-term cycling stability of 230 h@10 mA cm-2.

2.
Comput Methods Programs Biomed ; 232: 107440, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36881983

RESUMEN

BACKGROUND AND OBJECTIVES: Compressed sensing (CS) is often used to accelerate magnetic resonance image (MRI) reconstruction from undersampled k-space data. A novelty deeply unfolded networks (DUNs) based method, designed by unfolding a traditional CS-MRI optimization algorithm into deep networks, can provide significantly faster reconstruction speeds than traditional CS-MRI methods while improving image quality. METHODS: In this paper, we propose a High-Throughput Fast Iterative Shrinkage Thresholding Network (HFIST-Net) for reconstructing MR images from sparse measurements by combining traditional model-based CS techniques and data-driven deep learning methods. Specifically, the conventional Fast Iterative Shrinkage Thresholding Algorithm (FISTA) method is expanded as a deep network. To break the bottleneck of information transmission, a multi-channel fusion mechanism is proposed to improve the efficiency of information transmission between adjacent network stages. Moreover, a simple yet efficient channel attention block, called Gaussian context transformer (GCT), is proposed to improve the characterization capabilities of deep Convolutional Neural Network (CNN,) which utilizes Gaussian functions that satisfy preset relationships to achieve context feature excitation. RESULTS: T1 and T2 brain MR images from the FastMRI dataset are used to validate the performance of the proposed HFIST-Net. The qualitative and quantitative results showed that our method is superior to those compared state-of-the-art unfolded deep learning networks. CONCLUSIONS: The proposed HFIST-Net is capable of reconstructing more accurate MR image details from highly undersampled k-space data while maintaining fast computational speed.


Asunto(s)
Algoritmos , Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
3.
Skin Pharmacol Physiol ; 36(1): 27-37, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36693328

RESUMEN

INTRODUCTION: Tumor necrosis factor (TNF)-α released after follicular injury such as that caused by plucking plays a role in the activation of hair regeneration. Microneedle (MN) treatment is applied to the scalp to increase permeability and facilitate the delivery of any number of compounds. Because the MN treatment causes injury to the epidermis, albeit minor, we reasoned that this treatment would lead to a temporary TNF-α surge and thereby promote hair regeneration. METHODS: To investigate the effects of MN-treatment-induced microinjury and TNF-α on hair growth, we used C57BL/6N mice which were divided into six experimental groups: three groups of 1) negative control (NC), 2) plucking positive control (PK), and 3) MN therapy system (MTS) mice; and three groups identical to above were treated with a TNF-α blocker for 3 weeks: 4) NCB, 5) PKB, and 6) MTSB group. RESULTS: After injury, TNF-α surge occurred on day 3 in the PK group and on day 6 in the MTS group. Wnt proteins and VEGF expression were markedly increased in the PK group on day 3 and on day 6 in the MTS group compared to the NC group. Following wound healing, only MTS and PK groups displayed thickened epidermis and longer HF length. Within the 2 weeks following treatment, the rate of hair growth was much slower in the injured mice treated with the TNF-α blocker. CONCLUSION: Our findings indicate that microinjury stimulates the wound-healing mechanism via TNF-α/Wnt/VEGF surge to induce hair growth, and that blocking TNF-α inhibits this growth process.


Asunto(s)
Factor de Necrosis Tumoral alfa , Factor A de Crecimiento Endotelial Vascular , Ratones , Animales , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ratones Endogámicos C57BL , Cicatrización de Heridas , Cabello/metabolismo , Regeneración
4.
Entropy (Basel) ; 24(12)2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36554226

RESUMEN

A quantum battery consisting of an ensemble two-level atom is investigated. The battery is charged simultaneously by a harmonic field and an electrostatic field. The results show that the hybrid charging is superior to the previous case of only harmonic field charging in terms of battery capacity and charging power, regardless of whether the interaction between atoms is considered or not. In addition, the repulsive interaction between atoms will increase the battery capacity and charging power, while the attractive interaction between atoms will reduce the battery capacity and discharge power.

5.
Micromachines (Basel) ; 13(4)2022 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-35457897

RESUMEN

We propose a scheme to implement the phonon antibunching and phonon blockade in a circuit quantum acoustodynamical system containing two surface acoustic wave (SAW) resonators coupled to a superconducting qubit. In the cases of driving only one SAW resonator and two SAW resonators, we investigate the phonon statistics by numerically calculating the second-order correlation function. It is found that, when only one SAW cavity is resonantly driven, the phonon antibunching effect can be achieved even when the qubit-phonon coupling strength is smaller than the decay rates of acoustic cavities. This result physically originates from the quantum interference between super-Poissonian statistics and Poissonian statistics of phonons. In particular, when the two SAW resonators are simultaneously driven under the mechanical resonant condition, the phonon antibunching effect can be significantly enhanced, which ultimately allows for the generation of a phonon blockade. Moreover, the obtained phonon blockade can be optimized by regulating the intensity ratio of the two SAW driving fields. In addition, we also discuss in detail the effect of system parameters on the phonon statistics. Our work provides an alternative way for manipulating and controlling the nonclassical effects of SAW phonons. It may inspire the engineering of new SAW-based phonon devices and extend their applications in quantum information processing.

6.
Artículo en Inglés | MEDLINE | ID: mdl-34257685

RESUMEN

This study investigated the hypothesis that Portulaca oleracea L. exerts antiobesity and antidiabetic effects by evaluating blood lipid profiles, blood glucose control factors, protein expression of lipid metabolism, and insulin sensitivity improvement. Three groups of high-fat diet (HFD) induced obese C57BL/6 mice (n = 8) received treatment with low (5%; HFD + PO5%) or high (10%; HFD + PO10%) concentrations of P. oleracea powder for 12 weeks or no treatment (HFD) and were compared with each other and a fourth control group. Weight gain was reduced by 34% in the HFD + PO10% group compared to the HFD group. Moreover, the perirenal and epididymal fat contents in the HFD + PO10% group were 6.3-fold and 1.5-fold, respectively, lower than those in the HFD group. The atherogenic index (AI) and cardiac risk factor (CRF) results in the P. oleracea-treated groups were significantly lower than those in the HFD group. The homeostasis model assessment of insulin resistance (HOMA-IR) levels was lower in the HFD + PO10% group than in the HFD group. The protein expression levels of the proliferator-activated receptor (PPAR)-α, glucose transporter (GLUT) 4 and PPAR-γ were upregulated in the HFD + PO10% group compared to the HFD group. However, the protein expression levels of tumor necrosis factor (TNF)-α were lower in the P. oleracea-treated groups than in the HFD group. Our results demonstrate that P. oleracea powder could be effectively used to treat and prevent obesity and diabetes-associated diseases through suppression of weight gain and reduction in body fat and blood glucose levels.

7.
Artículo en Inglés | MEDLINE | ID: mdl-33790980

RESUMEN

This study investigated the hair regeneration promotion and hair loss prevention properties of Nelumbinis Semen (NS) extract in vitro and in vivo. The effect of NS on the proliferation and migration of human dermal papilla cells (hDPCs) was measured in vitro via CCK-8 and scratch migration assays, after which the antioxidant activity of NS was also quantified. NS extracts were then applied to the back of 7-week-old C57BL/6 mice for 3 weeks to monitor hair growth patterns and hair follicle (HF) histology. The mice were divided into three groups: negative control group (NC; DMSO), positive control group (PC; 3% minoxidil), and experimental group (NS extract 1,000 ppm). Moreover, to study the molecular mechanisms by which NS extract regenerates hair growth, real-time PCR was used to analyze factors related to the hair growth cycle. The NS extracts were found to possess high antioxidant properties due to their high flavonoid contents and electron-donating ability. Moreover, NS extracts enhanced hDPC proliferation and migration in a concentration-dependent manner (15.63-125 ppm). The hair growth index and growth area of the NS group (2.81 score, 81%) on day 14 were higher than those of the PC group (2.65 score, 68%) (p < 0.05). Additionally, the HFs of the NS group were located deep in the subcutis, similar to the PC group with developed hair roots. Moreover, the mRNA expression of VEGF and IGF-1 was higher in the NS group compared to the PC group, whereas TGF-ß1 expression was lower (p < 0.05). Our findings indicate that NS modulates hair growth by increasing IGF-1 and VEGF expression while inhibiting that of TGF-ß1. Therefore, our findings suggest that NS extract is a promising new hair loss treatment derived from a natural substance that helps promote hair growth and prevent hair loss.

8.
Nutrients ; 12(9)2020 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-32878096

RESUMEN

It is well known that reducing consumption of sugar is a global public health priority. Beverages were the primary source of total sugar intake from processed foods. However, there are few studies investigating the trend of beverage consumption among children and adolescents in Korea. We examined the overall trend in beverage consumption among 11,996 participants aged 10-18 years who were enrolled in the Korea National Health and Nutrition Examination Survey (KNHANES) (1998-2018). Further, we examined the effect of beverage types on beverage consumption-related demographic factors and obesity among 6121 participants using the recent 24 h dietary recall data (2010-2018) that captured the consumption of fruit and vegetable juices, soft drinks, milk and milk-based products and alcoholic beverages. Demographic characteristics, including sex, age, body mass index, household income level and residential area, were considered. Consumers' overall beverage intake and the percentage of energy derived from fruit and vegetable juices and soft drinks steadily increased from 1998 to 2016-2018 (p-trend < 0.0001); in contrast, dairy product consumption declined since 2010-2012. The main sources of beverage-based calories were fruit and vegetable juices (107.5 kcal/day), soft drinks (145.2 kcal/day), dairy products (181.8 kcal/day) and alcoholic beverages (103.5 kcal/day). Also, Korean adolescents aged 16-18 years consumed more soft drinks, fewer dairy products and higher alcoholic drinks than other age groups; particularly, boys consumed more energy from beverages (p < 0.0001). The odds ratios of obesity prevalence tended to be higher for soft drink consumption than for other beverages but this was not significant. The consumption of fruit and vegetable juices and milk and milk products showed a marginal association with a reduced risk of obesity prevalence. Since beverage consumption has increased steadily among Korean children and adolescents, appropriate interventions are needed. In the future, data from a larger sample of Korean children and adolescents are necessary to identify significant differences and longitudinal studies are necessary to examine the causalities.


Asunto(s)
Bebidas , Demografía , Dieta , Obesidad Infantil/epidemiología , Factores Socioeconómicos , Adolescente , Bebidas Alcohólicas , Animales , Estatura , Índice de Masa Corporal , Peso Corporal , Bebidas Gaseosas , Niño , Estudios Transversales , Registros de Dieta , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/análisis , Femenino , Jugos de Frutas y Vegetales , Humanos , Masculino , Recuerdo Mental , Leche , Encuestas Nutricionales , Prevalencia , Ingesta Diaria Recomendada , República de Corea/epidemiología
9.
Pharm Biol ; 58(1): 400-409, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32420784

RESUMEN

Context: Although Salvia plebeia (SP) R. Brown (Labiatae) is known to possess various biological activities, the effects of SP on hair growth have not been elucidated.Objective: To investigate the hair growth potential of SP extract by using human dermal papilla cells (hDPCs) and C57BL/6 mice.Materials and methods: The entire SP plant sample was ground into powder and extracted with 99.9% methyl alcohol. Various concentrations of SP extract were added to hDPCs to evaluate the proliferation, migration, and factors related to hair growth and cycling. Effect of topical SP administration on hair regrowth was tested in vivo in male C57BL/6 mice for 21 days.Results: SP extract significantly increased the proliferation of cultured hDPCs at doses of 15.6 and 31.3 µg/mL compared to control group by 123% and 132%, respectively. Expression of hepatocyte growth factor increased while the level of TGF-ß1 and SMAD2/3 decreased when treated with SP extract. At the molecular level, the extract activated Wnt/ß-catenin signalling by raising ß-catenin and phospho-GSK3ß expression. SP extract also exerted anti-apoptotic and proliferative effects in hDPCs by increasing the Bcl-2/Bax ratio and activating cell proliferation-related proteins, ERK and Akt. Finally, the extract caused an induction of the anagen phase leading to significantly enhanced hair growth in treated male mice.Discussion and conclusion: Our results indicate that SP extract has the capacity to activate hDPCs into a proliferative state to promote hair growth. Further research is necessary to determine the bioactive components and their mechanisms of action responsible for SP-related hair growth effect.


Asunto(s)
Folículo Piloso/efectos de los fármacos , Folículo Piloso/crecimiento & desarrollo , Extractos Vegetales/farmacología , Salvia , Animales , Proliferación Celular/efectos de los fármacos , Proliferación Celular/fisiología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Cabello/citología , Cabello/efectos de los fármacos , Cabello/crecimiento & desarrollo , Folículo Piloso/citología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Extractos Vegetales/aislamiento & purificación
10.
J Vet Med Sci ; 82(2): 224-228, 2020 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-31866631

RESUMEN

The objective of this study was to compare the efficacy of a porcine reproductive and respiratory syndrome virus (PRRSV)-1 and PRRSV-2 modified-live virus (MLV) vaccines when administered at 1 day of age under field conditions. The piglets elicited anti-PRRSV antibodies at 1 day of age even in the presence of maternally derived antibodies. The number of PRRSV-2 genomic copies in the sera of pigs from the PRRSV-2 MLV-vaccinated pigs was significantly (P<0.05) lower when compared to PRRSV-1 MLV-vaccinated pigs. The average daily gain in PRRSV-2 MLV-vaccinated pigs was significantly (P<0.05) higher when compared to both PRRSV-1 MLV-vaccinated and unvaccinated pigs. This study demonstrated that vaccination as early as 1 day of age was effective against PRRSV infection.


Asunto(s)
Síndrome Respiratorio y de la Reproducción Porcina/prevención & control , Virus del Síndrome Respiratorio y Reproductivo Porcino/inmunología , Sus scrofa/crecimiento & desarrollo , Vacunación/veterinaria , Vacunas Virales/inmunología , Animales , Animales Recién Nacidos , Anticuerpos Antivirales/sangre , Granjas , Femenino , Inmunidad Materno-Adquirida , Masculino , Síndrome Respiratorio y de la Reproducción Porcina/inmunología , República de Corea , Porcinos , Vacunas Atenuadas/inmunología , Vacunas Virales/administración & dosificación
11.
Yao Xue Xue Bao ; 47(1): 34-8, 2012 Jan.
Artículo en Chino | MEDLINE | ID: mdl-22493802

RESUMEN

This study is to investigate the anti-allergic effect of anthocyanidin and to explore its possible mechanism. The experiments of passive cutaneous anaphylaxis reaction (PCA) and colorimetry were used to determine the effect of anthocyanidin on degranulation of mast cells in vivo. For in vitro study, various concentrations of anthocyanidin (100, 50 and 25 micromol x L(-1)) were added to the culture medium of mast cells cultured with 100 microg x L(-1) of dinitrophenyl (DNP) specific IgE overnight. The azelastine (100 micromol x L(-1)) was selected as the positive control. The antigen (DNP-human serum albumin, DNP-HAS)-induced release of degranulation was measured by enzymatic assay, histamine was determined by EIA, and interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were measured by Western blotting, separately. In addition, the effects of anthocyanidin on phosphorylation of NF-kappaB, p38MAPK and Akt were observed by Western blotting. The results showed that treatments with anthocyanidin (100 and 50 mg x kg(-1)) were followed by a decrease in PCA of rats. Anthocyanidin (100 and 50 micromol x L(-1)) obviously suppressed the degranulation from mast cells, whereas results from anthocyanidin (100 and 50 micromol x L(-1)) group indicated significant inhibitory effect on histamine, the calcium uptake, TNF-alpha, IL-6, phosphorylation of NF-kappaB, p38MAPK and Akt of mast cells induced by antigen. Anthocyanidin may suppress the anaphylactic reaction by inhibiting the action of mast cells. NF-kappaB, p38MAPK and Akt at least in part contribute to this event.


Asunto(s)
Antocianinas/farmacología , Antialérgicos/farmacología , Mastocitos/metabolismo , Anafilaxis Cutánea Pasiva/efectos de los fármacos , Animales , Calcio/metabolismo , Degranulación de la Célula/efectos de los fármacos , Liberación de Histamina/efectos de los fármacos , Inmunoglobulina E/inmunología , Interleucina-6/metabolismo , Masculino , Mastocitos/inmunología , Mastocitos/fisiología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Factor de Transcripción ReIA/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
12.
Phys Rev Lett ; 99(17): 170405, 2007 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-17995306

RESUMEN

A simple scheme for storage of spin squeezing in a two-component Bose-Einstein condensate is investigated by considering rapidly turning-off the external field at a time that maximal spin squeezing occurs. We show that strong reduction of spin fluctuation can be maintained in a nearly fixed direction. We explain the underlying physics using the phase model and present analytical expressions of the maximal-squeezing time and the corresponding squeezing parameter.

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