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1.
Plant Mol Biol ; 114(1): 10, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38319430

RESUMEN

Quinoa seeds are gluten- and cholesterol-free, contain all amino acids required by the human body, have a high protein content, provide endocrine regulation, protein supplementation, and cardiovascular protection effects. However, metabolite accumulation and transcriptional regulatory networks in quinoa seed development are not well understood. Four key stages of seed development in Dianli-3260 and Dianli-557 were thus analyzed and 849 metabolites were identified, among which sugars, amino acids, and lipids were key for developmental processes, and their accumulation showed a gradual decrease. Transcriptome analysis identified 40,345 genes, of which 20,917 were differential between the M and F phases, including 8279 and 12,638 up- and down-regulated genes, respectively. Grain development processes were mainly enriched in galactose metabolism, pentose and glucuronate interconversions, the biosynthesis of amino acids, and carbon metabolism pathways, in which raffinose, phosphoenolpyruvate, series and other metabolites are significantly enriched, gene-LOC110689372, Gene-LOC110710556 and gene-LOC110714584 are significantly expressed, and these metabolites and genes play an important role in carbohydrate metabolism, lipid and Amino acid synthesis of quinoa. This study provides a theoretical basis to expand our understanding of the molecular and metabolic development of quinoa grains.


Asunto(s)
Chenopodium quinoa , Transcriptoma , Humanos , Chenopodium quinoa/genética , Metaboloma/genética , Semillas/genética , Aminoácidos
2.
BMC Plant Biol ; 23(1): 292, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37264351

RESUMEN

BACKGROUND: Quinoa (Chenopodium quinoa Willd.) originates in high altitude areas, such as the Andes, and has some inherent characteristics of cold, drought, and salinity tolerance, but is sensitive to high temperature. RESULTS: To gain insight into the response mechanism of quinoa to high temperature stress, we conducted an extensive targeted metabolomic study of two cultivars, Dianli-3101 and Dianli-3051, along with a combined transcriptome analysis. A total of 794 metabolites and 54,200 genes were detected, in which the genes related to photosynthesis were found down-regulated at high temperatures, and two metabolites, lipids and flavonoids, showed the largest changes in differential accumulation. Further analysis of the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and transcription factors revealed that quinoa inhibits photosynthesis at high temperatures, and the possible strategies being used for high temperature stress management are regulation of heat stress transcription factors (HSFs) to obtain heat tolerance, and regulation of purine metabolism to enhance stress signals for rapid response to high temperature stress. The tolerant genotype could have an enhanced response through lower purine levels. The induction of the stress response could be mediated by HSF transcription factors. The results of this study may provide theoretical references for understanding the response mechanism of quinoa to high temperature stress, and for screening potential high temperature tolerant target genes and high temperature tolerant strains. CONCLUSIONS: These findings reveal the regulation of the transcription factor family HSF and the purinergic pathway in response to high temperature stress to improve quinoa varieties with high temperature tolerance.


Asunto(s)
Chenopodium quinoa , Plantones , Plantones/genética , Chenopodium quinoa/fisiología , Temperatura , Transcriptoma , Perfilación de la Expresión Génica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
3.
Small ; 19(28): e2300915, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36970813

RESUMEN

The integration of fog collection and solar-driven evaporation has great significance in addressing the challenge of the global freshwater crisis. Herein, a micro/nanostructured polyethylene/carbon nanotubes foam with interconnected open-cell structure (MN-PCG) is fabricated using an industrialized micro extrusion compression molding technology. The 3D surface micro/nanostructure provides sufficient nucleation points for tiny water droplets to harvest moisture from humid air and a fog harvesting efficiency of 1451 mg cm-2 h-1 is achieved at night. The homogeneously dispersed carbon nanotubes and the graphite oxide@carbon nanotubes coating endow the MN-PCG foam with excellent photothermal properties. Benefitting from the excellent photothermal property and sufficient steam escape channels, the MN-PCG foam attains a superior evaporation rate of 2.42 kg m-2 h-1 under 1 Sun illumination. Consequently, a daily yield of ≈35 kg m-2 is realized by the integration of fog collection and solar-driven evaporation. Moreover, the robust superhydrophobicity, acid/alkali tolerance, thermal resistance, and passive/active de-icing properties provide a guarantee for the long-term work of the MN-PCG foam during practical outdoor applications. The large-scale fabrication method for an all-weather freshwater harvester offers an excellent solution to address the global water scarcity.

4.
Photodermatol Photoimmunol Photomed ; 39(3): 235-245, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35950642

RESUMEN

BACKGROUND: Mesenchymal stem cells-derived exosome (MSCs-exo) was identified to reduce photoaging. The purpose of this study was to investigate the potential role of microRNA (miR)-29b-3p derived from bone marrow MSCs-exo (BMSCs-exo) in photoaging. METHODS: Exosomes were isolated from BMSCs and verified by Western blot. A photoaging cell model was constructed by UVB irradiation of human dermal fibroblasts (HDFs). Quantitative real-time PCR (RT-qPCR) was performed to detect the mRNA levels of miR-29b-3p, collagen type I and matrix metalloproteinases (MMPs). CCK-8, Transwell and flow cytometry were applicated to examine cell viability, migration and apoptosis. Commercial kits are used to measure levels of oxidative stress indicators. Finally, a dual-luciferase reporter assay was applied to validate the target of miR-29b-3p. RESULTS: Extracted exosomes were positive for HSP70 and CD9. Survival of HDFs increased in an exosome concentration-dependent manner. UVB irradiation inhibited miR-29b-3p levels compared with controls, but BMSCs-exo treatment restored miR-29b-3p levels (p < .05). Additionally, BMSCs-exo-miR-29b-3p reversed the inhibition of HDFs migration and oxidative stress by UVB irradiation, as well as the promotion of apoptosis. However, this reversal was attenuated by the suppression of miR-29b-3p (p < .05). Furthermore, BMSCs-exo-miR-29b-3p also inhibited the degradation of collagen type I and the production of MMPs in photoaging, and they were also eliminated by the reduced miR-29b-3p. Finally, MMP-2 was the target gene of miR-29b-3p. CONCLUSION: Our study presented a novel role for BMSCs-exo-miR-29b-3p in improving skin photoaging function, and these findings may provide new insights into the targeted treatment of skin photoaging.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , MicroARNs , Envejecimiento de la Piel , Humanos , Colágeno Tipo I/genética , Envejecimiento de la Piel/genética , Exosomas/genética , Exosomas/metabolismo , MicroARNs/genética , Células Madre Mesenquimatosas/metabolismo , Fibroblastos/metabolismo
5.
Skin Pharmacol Physiol ; 36(2): 98-106, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36746125

RESUMEN

INTRODUCTION: The role of bone marrow mesenchymal stem cells-derived exosomes (BMSCs-exo) in skin photoaging was explored in human dermal fibroblasts (HDFs). The underlying mechanism was further explored. METHODS: HDFs were exposed to UVB irradiation to establish the cell photodamage models. The cell viability and levels of oxidative stress-related factors were tested. ELISA was done to detect TNF-α, IL-6, and IL-1ß concentrations. Western blot was applied for protein examination. RESULTS: UVB treatment led to the inhibition of cell viability. But after BMSCs-exo addition, the inhibitory effect was returned in a dose manner. UVB exposure contributed to the increase of reactive oxygen species and LDH and the downregulation of superoxide dismutase. In addition, excessive secretion of TNF-α, IL-6, and IL-1ß was also detected in cells exposed to UVB. However, BMSCs-exo addition eliminated the effects of UVB on oxidative stress and inflammation in HDFs. BMSCs-exo inhibited matrix metalloproteinases MMP-1 and MMP-3 expression but promoted collagen I expression. UVB radiation activated the MAPK/AP-1 signaling, manifested as the increase of p-p38, c-Jun, and c-Fos protein levels, which were reversed by BMSCs-exo. As a p38 agonist, anisomycin counteracted the effect of BMSCs-exo on HDF's viability, oxidative stress, and inflammation. CONCLUSION: BMSCs-exo protected HDFs against UVB-induced inhibition of cell viability and the activation of cell oxidative stress and inflammation, which might be related to the inhibition of the MAPK/AP-1 signaling pathway.


Asunto(s)
Exosomas , Envejecimiento de la Piel , Humanos , Factor de Transcripción AP-1/metabolismo , Factor de Transcripción AP-1/farmacología , Interleucina-6/metabolismo , Interleucina-6/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Exosomas/metabolismo , Piel/metabolismo , Transducción de Señal , Metaloproteinasa 1 de la Matriz/metabolismo , Fibroblastos , Inflamación/metabolismo , Rayos Ultravioleta/efectos adversos
6.
Int J Mol Sci ; 24(14)2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37511340

RESUMEN

Quinoa (Chenopodium quinoa Willd.) is a dicotyledonous annual amaranth herb that belongs to the family Chenopodiaceae. Quinoa can be cultivated across a wide range of climatic conditions. With regard to its cultivation, nitrogen-based fertilizers have a demonstrable effect on the growth and development of quinoa. How crops respond to the application of nitrogen affects grain quality and yield. Therefore, to explore the regulatory mechanisms that underlie the responses of quinoa seedlings to the application of nitrogen, we selected two varieties (i.e., Dianli-1299 and Dianli-71) of quinoa seedlings and analyzed them using metabolomic and transcriptomic techniques. Specifically, we studied the mechanisms underlying the responses of quinoa seedlings to varying concentrations of nitrogen by analyzing the dynamics of metabolites and genes involved in arginine biosynthesis; carbon fixation; and alanine, aspartate, and glutamate biosynthetic pathways. Overall, we found that differentially expressed genes (DEGs) and differentially expressed metabolites (DEMs) of quinoa are affected by the concentration of nitrogen. We detected 1057 metabolites, and 29,012 genes were annotated for the KEGG. We also found that 15 DEMs and 8 DEGs were key determinants of the differences observed in quinoa seedlings under different nitrogen concentrations. These contribute toward a deeper understanding of the metabolic processes of plants under different nitrogen treatments and provide a theoretical basis for improving the nitrogen use efficiency (NUE) of quinoa.


Asunto(s)
Chenopodium quinoa , Transcriptoma , Chenopodium quinoa/metabolismo , Plantones/genética , Plantones/metabolismo , Fertilizantes , Nitrógeno/metabolismo , Metaboloma
7.
BMC Plant Biol ; 22(1): 604, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36539684

RESUMEN

BACKGROUND: Quinoa (Chenopodium quinoa Willd.) is a herb within the Quinoa subfamily of Amaranthaceae, with remarkable environmental adaptability. Its edible young leaves and grains are rich in protein, amino acids, microorganisms, and minerals. Although assessing the effects of fertilization on quinoa yield and quality has become an intensive area of research focus, the associated underlying mechanisms remain unclear. As one of the three macro nutrients in plants, potassium has an important impact on plant growth and development. In this study, extensive metabolome and transcriptome analyses were conducted in quinoa seedlings 30 days after fertilizer application to characterize the growth response mechanism to potassium.  RESULTS: The differential metabolites and genes present in the seedlings of white and red quinoa cultivars were significantly enriched in the photosynthetic pathway. Moreover, the PsbQ enzyme on photosystem II and delta enzyme on ATP synthase were significantly down regulated in quinoa seedlings under potassium deficiency. Additionally, the differential metabolites and genes of red quinoa seedlings were significantly enriched in the arginine biosynthetic pathway. CONCLUSIONS: These findings provide a more thorough understanding of the molecular changes in quinoa seedlings that occur under deficient, relative to normal, potassium levels. Furthermore, this study provides a theoretical basis regarding the importance of potassium fertilizers, as well as their efficient utilization by growing quinoa seedlings.


Asunto(s)
Chenopodium quinoa , Chenopodium quinoa/química , Plantones/genética , Transcriptoma , Potasio/metabolismo , Metaboloma
8.
Small ; 18(17): e2200175, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35307967

RESUMEN

Solar evaporation is one of the most attractive and sustainable approaches to address worldwide freshwater scarcity. Unfortunately, it is still a crucial challenge that needs to be confronted when the solar evaporator faces harsh application environments. Herein, a promising polymer molding method that combines melt blending and compression molding, namely micro extrusion compression molding, is proposed for the cost-effective fabrication of lightweight polyethylene/graphene nanosheets (PE/GNs) foam with interconnected vapor escape channels and surface micro-nanostructures. A contact angle of 155 ± 2°, a rolling angle of 5 ± 1° and reflectance of ≈1.6% in the wavelength range of 300-2500 nm appears on the micro-nanostructured PE/GNs foam surface. More interestingly, the micro-nanostructured PE/GNs foam surface can maintain a robust superhydrophobic state under dynamic impacting, high temperature and acid-/alkali solutions. These results mean that the micro-nanostructured PE/GNs foam surface possesses self-cleaning, anti-icing and photothermal deicing properties at the same time. Importantly, the foam exhibits an evaporation rate of 1.83 kg m-2 h-1 under 1 Sun illumination and excellent salt rejecting performance when it is used as a self-floating solar evaporator. The proposed method provides an ideal and industrialized approach for the mass production of solar evaporators suitable for practical application environments.


Asunto(s)
Grafito , Nanoestructuras , Purificación del Agua , Álcalis , Análisis Costo-Beneficio , Interacciones Hidrofóbicas e Hidrofílicas , Pinzas Ópticas , Polietileno
9.
Soft Matter ; 18(17): 3412-3421, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35420622

RESUMEN

Superhydrophobic silicone rubbers with robust physical and chemical stability have promising application potential in the field of flexible electronics. A one-step laser etching strategy is proposed for successfully fabricating superhydrophobic silicone rubbers with bioinspired hierarchical micro/nanostructures. Regular and dense micro/nano spheres gradually accumulate on the modified silicone rubber surface with the increase of laser etching cycles. Owing to the bioinspired hierarchical micro/nano spheres, a 5 µL water droplet on the modified silicone rubber surface exhibits a contact angle of 158 ± 3° and a sliding angle of 5 ± 1°. Moreover, the modified silicone rubber can maintain a stable superhydrophobic state in acid/alkali (pH = 2, 4, 6, 8, and 10) and thermal environments (50-90 °C). Importantly, the contact angle and sliding angle are adjustable depending on the number of laser etching cycles, which is beneficial for the different application requirements. The proposed method for the fast fabrication of superhydrophobic silicone rubbers with tunable wettability can provide an excellent candidate for the protection of flexible electronics in rainy and acid/alkali environments.

10.
Macromol Rapid Commun ; 43(18): e2200387, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35689512

RESUMEN

With the rapid advance of electronics, the light, flexible, and multifunctional composite films with high electromagnetic interference (EMI) shielding effectiveness and excellent thermal management are highly desirable for next-generation portable and wearable electronic devices. Herein, a series of flexible and ultrathin natural rubber/MXene/carbon nanotubes (NR/MXene/CNTs) composite films with sandwich structure are constructed layer by layer through a facile vacuum-assisted filtration method for EMI shielding and Joule heating application. The fabricated NR/MXene/CNTs-50 composite film, with NR/MXene as inner layer and NR/CNTs as out layers, not only has high EMI shielding efficiency, but also has excellent comprehensive mechanical properties at the thickness of only 200 µm. In addition, the superior environmental durability, high electrothermal conversion efficiency, hydrophobicity, and fine performance stability after periodic cyclic bending make the film possess more value in practical application.


Asunto(s)
Nanotubos de Carbono , Fenómenos Electromagnéticos , Goma
11.
Int J Mol Sci ; 23(9)2022 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-35563095

RESUMEN

Quinoa (Chenopodium quinoa Willd.) is a dicotyledonous annual herb of Family Amaranthaceae and Subfamily Chenopodiaceae. It has high nutritional and economic value. Phosphorus (P) is an essential plant macronutrient, a component of many biomolecules, and vital to growth, development, and metabolism. We analyzed the transcriptomes and metabolomes of Dianli-1299 and Dianli-71 quinoa seedlings, compared their phenotypes, and elucidated the mechanisms of their responses to the phosphorus treatments. Phenotypes significantly varied with phosphorus level. The plants responded to changes in available phosphorus by modulating metabolites and genes implicated in glycerophospholipid, glycerolipid and glycolysis, and glyconeogenesis metabolism. We detected 1057 metabolites, of which 149 were differentially expressed (DEMs) and common to the control (CK) vs. the low-phosphorus (LP) treatment samples, while two DEMs were common to CK vs. the high-phosphorus (HP) treatment samples. The Kyoto Encyclopedia of genes and genomes (KEGG) annotated 29,232 genes, of which 231 were differentially expressed (DEGs) and common to CK vs. LP, while one was common to CK vs. HP. A total of 15 DEMs and 11 DEGs might account for the observed differences in the responses of the quinoa seedlings to the various phosphorus levels. The foregoing results may provide a theoretical basis for improving the phosphorus utilization efficiency in quinoa.


Asunto(s)
Chenopodium quinoa , Chenopodium quinoa/genética , Chenopodium quinoa/metabolismo , Metaboloma , Fósforo/metabolismo , Plantones/genética , Plantones/metabolismo , Transcriptoma
12.
Int J Mol Sci ; 23(9)2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35563578

RESUMEN

Spot blotch (SB) is a fungal disease that threatens wheat yield and quality. Presently, the molecular mechanism against SB is unclear. In this study, the resistant variety Zhenkang iron shell wheat (Yunmai 0030) and susceptible variety Lincang iron shell wheat (Yunmai 0608) were selected by identifying SB of Yunnan iron shell wheat. The metabolome and transcriptome of leaves of two varieties at different positions were detected using the systemic acquired resistance theory to investigate the molecular and physiological changes in Yunnan iron shell wheat under SB stress. We found that the genes and metabolites related to benzoxazinoid biosynthesis and arginine and proline metabolism were highly enriched after infection with leaf blight. The enriched differential metabolites mainly included phenolic acids, alkaloids, and flavonoids. We further observed that DIBOA- and DIMBOA-glucoside positively affected iron shell wheat resistance to leaf blight and proline and its derivatives were important for plant self-defense. Furthermore, we confirmed that the related metabolites in benzoxazinoid biosynthesis and arginine and proline metabolism positively affected Triticum aestivum ssp. resistance to SB. This study provides new insights into the dynamic physiological changes of wheat in response to SB, helps us better understand the mechanism of resistance to SB, and contributes to the breeding and utilization of resistant varieties.


Asunto(s)
Ascomicetos , Triticum , Arginina/genética , Ascomicetos/genética , Benzoxazinas , China , Resistencia a la Enfermedad/genética , Hierro , Metaboloma , Fitomejoramiento , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Prolina/genética , Transcriptoma , Triticum/genética , Triticum/microbiología
13.
Small ; 17(28): e2100017, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34110680

RESUMEN

Producing high-quality graphene and polymer/graphene nanocomposite is facing the problems of complex procedure, low efficiency, and serious resource waste. To explore a new fabrication approach with high efficiency and low cost is crucial for solving these technical issues, which becomes a current research hotspot and also a great challenge. Herein, a one-step melt mixing strategy based on the synergy of steam explosion and alternating convergent-divergent flow, is innovatively developed to fabricate high-density polyethylene (HDPE)/graphene nanocomposites using industrial-grade expanded graphite (EG) without chemical agents and complex procedures. The co-action of the external force derived from elongational melts and the internal force generated by steam explosion make EG ultrafastly exfoliate into few-layer graphene nanosheets (GNS) and simultaneously disperse in melts within 4 min. The as-produced GNS have a lateral size of over 5 µm and a minimum thickness of 1.4 nm, can introduce super heterogeneous nucleation to HDPE macromolecules and greatly increases nanocomposite crystallinity up to 86.5%. Moreover, plentiful HDPE crystallites and well-dispersed GNS jointly form an improved thermally-conductive network, making nanocomposites with a rapid-respond ability in solar-to-thermal conversion and heat dissipation. This facile strategy will facilitate the development of scalable production and wide application of high-performance graphene and highly-filled nanocomposites.

14.
Soft Matter ; 17(7): 1901-1911, 2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33416069

RESUMEN

Facing various problems caused by icing in daily life, preparing photothermal deicing materials with wide applicability in high efficiency and low cost is not only a current research hotspot but also a great challenge. Herein, an economical spray-coating method is applied to prepare high-efficiency flexible photothermal icephobic copper mesh using micro silicon carbide (SiC) particles as photothermal conversion material and nano silica (SiO2) particles as a surface superhydrophobic modifier. Owing to the excellent hierarchical micro-nanostructures, the SiC/SiO2 coated copper mesh exhibits a water contact angle (CA) of 162 ± 2° and a sliding angle (SA) of 3 ± 2°. Interestingly, the coated copper mesh exhibits exceptional mechanical durability against water droplet and water flow impact, repeated bending-twisting and tape-peeling. Benefitting from the robust superhydrophobicity, the SiC/SiO2 coating on the copper mesh can significantly delay the freezing time of the droplets and reduce the ice adhesion strength. Furthermore, the coated copper mesh well retains the good photothermal conversion and thermal conductivity properties of the micro SiC particles. Under NIR irradiation, the surface temperature of the coated copper mesh placed on the ice layer can increase by 35.3 °C in 220 s, so that it can rapidly melt the accumulated frost and ice layer on the inner wall of the refrigerator. The presented flexible photothermal icephobic copper mesh exhibits enormous potential when applied to remove ice from apparatus that is accessible, such as road, overhead transmission lines and power networks owing to its flexibility, economy, and high energy efficiency.

15.
Nanotechnology ; 32(39)2021 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-34126610

RESUMEN

The fine nanopillars on the natural cicada wing, which exhibits outstanding superhydrophobicity and anti-reflectivity, are carefully observed and analyzed. Here, a promising strategy by combining anodic aluminum oxide template and hot embossing is proposed for rapidly and efficiently mimicking the orderly and densely arranged nanopillars on the cicada wing surface to polypropylene (PP) surfaces. By adjusting the compression pressure, the nanostructures on the PP replica surface gradually evolve from nanoprotrusion-like features to nanopillar-like features so that a gradient wetting behavior from hydrophilicity to hydrophobicity and further to superhydrophobicity appears on the PP replica surfaces. Specifically, the biomimetic PP replica surface exhibits a contact angle of 159 ± 3° and a rolling angle of 8 ± 3° at a compression pressure of 15 MPa. Moreover, the biomimetic PP replica surface can stabilize its superhydrophobic state under a 1.96 kPa external pressure during the dynamic droplet impact. Besides robust dynamic superhydrophobicity, the biomimetic PP replica surface also demonstrated excellent anti-reflectivity because of the gradually changed effective refractive index. Therefore, the biomimetic PP replica inherits both the superhydrophobicity and anti-reflectivity of the natural cicada wing, which makes the products can effectively reduce the external damage when applied to agricultural films, dustproof films, and packaging materials.

16.
Opt Lett ; 45(3): 746-749, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32004300

RESUMEN

Random vibrations were employed to pick up each monochromatic component in a continuous-wave cavity ringdown spectroscopy (CRDS) system using a bichromatic laser source. Light frequencies were selected within flat portions of an absorption profile to suppress the jitter in laser frequency during measurements. An interference effect caused by cavity length variations was suppressed by optimizing the initial fit point for each ringdown transient. The difference in exponential decay rates of two frequencies determined the gas mole fraction, and no calibration of empty cavity losses was necessary. Experiments on varying humidity were conducted, and the results agreed with the readings of a commercial hygrometer.

17.
Opt Express ; 27(3): 2899-2914, 2019 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-30732320

RESUMEN

In this paper, a precise phase-shift extraction method was introduced for the first time to measure the thickness distribution of transparent glass films. A spatial light modulator modulated the phases of the incident laser in a large lateral shearing interferometer. The phase shifting caused by the thickness of the films can be extracted ranging from 0 to 2π, in a recursive way suitable for real-time implementation. Incident lasers with different wavelengths were utilized to measure the spatial distribution of the thickness of the films, and they can be larger than one wavelength of the incident light. Both artificial and experimental results have verified that the resolution of the thickness measurement reaches up to 1 𝛍m.

18.
Ecotoxicol Environ Saf ; 164: 131-139, 2018 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-30107322

RESUMEN

Olaquindox as one of the effective antimicrobial agents and growth-promoting feed additives, had been widely used in animal and fish production. However, few studies have been done to unveil its possible toxic effect and tissue injury on aquatic animal. In this study, the toxic effect and underlying mechanisms of olaquindox toxicity were investigated in common carp when feed with different doses of olaquindox for 90 days. The morbidity and mortality, pathological changes, hematology parameters, residue concentration in the tissues of common carp were assessed, hepatocyte apoptosis was detected through ultrastructural observation and flow cytometry methods. The results showed that the morbidity and mortality increased with the increasing dosages of dietary olaquindox, subchronic exposure to olaquindox caused remarkably pathological changes, including congestion and bleeding, intramuscular edema, vacuolar degeneration, degeneration and deformation in renal tubules architecture, respiratory epithelium fusion and intestinal epithelial microvilli disintegration. Besides, dietary olaquindox led to significant changes in blood biochemical parameters including red blood cell, hemoglobin, alanine aminotransferase and aspartate aminotransferase, an elevated residue concentration of olaquindox was detected in liver and kidney after exposure, hepatocyte apoptosis and necrosis were observed. Moreover, insulin-like growth factor I (IGF-I) mRNA level in liver was higher than normal level with the dose below 25 mg/kg olaquindox and was lower than normal level with the dose above 50 mg/kg. Our results demonstrated that dietary olaquindox may pose subchronic toxicity and residue in fish organs and provided scientific data for the safe application of olaquindox in fish.


Asunto(s)
Apoptosis/efectos de los fármacos , Carpas , Exposición Dietética/efectos adversos , Hepatocitos/efectos de los fármacos , Quinoxalinas/toxicidad , Alanina Transaminasa/metabolismo , Animales , Aspartato Aminotransferasas/metabolismo , Dieta/veterinaria , Factor I del Crecimiento Similar a la Insulina/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Ingesta Diaria Recomendada , Alimentos Marinos/análisis , Pruebas de Toxicidad Subcrónica
19.
J Cosmet Laser Ther ; 19(6): 337-344, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28388236

RESUMEN

BACKGROUND: The fractional radiofrequency (fRF) technique is a recently emerged technique. However, the exact outcomes of fRF for treating atrophic acne scar in Asians are still unclear. OBJECTIVE: To compare the clinical outcomes of fRF with the fractional laser technique in Asians with atrophic acne scar. MATERIALS AND METHODS: The databases MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Chinese National Knowledge Infrastructure (CNKI) were searched. Main clinical outcomes were participant-reported scar improvement, investigator-reported scar improvement, post-inflammatory hyperpigmentation (PIH), erythema duration, scab duration, and the pain level. RESULT: Six randomized controlled trials were included in this meta-analysis. The scar improvement was similar in both groups regarding participant-reported scar improvement (p = 0.48) and investigator-reported scar improvement (p = 0.89). However, the incidence of PIH in fRF group was lower in comparison with the laser group (p < 0.001). The average duration of erythema was shorter in fRF group than in the laser group (p < 0.001). The mean time for debridement was shorter in fRF group than the carbon dioxide fractional laser system (p = 0.02). The pain level did not differ significantly in the two groups (p = 0.53). CONCLUSION: Although some bias exists in our study, fRF appears to be a superior alternative for the treatment of atrophic acne scar in Asians.


Asunto(s)
Acné Queloide/radioterapia , Pueblo Asiatico , Láseres de Gas/uso terapéutico , Terapia por Luz de Baja Intensidad/métodos , Terapia por Radiofrecuencia , Técnicas Cosméticas , Eritema/etiología , Humanos , Hiperpigmentación/etiología , Terapia por Luz de Baja Intensidad/efectos adversos , Ondas de Radio/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto
20.
Opt Express ; 24(11): 11475-82, 2016 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-27410075

RESUMEN

Simultaneous temperature and strain sensing is experimentally demonstrated based on erbium-doped fiber laser (EDFL) and Brillouin erbium fiber laser (BEFL) incorporated in a single ring laser cavity. The EDFL can be switched to BEFL by injecting the Brillouin pump into the laser cavity. Longitudinal modes beat frequency and Brillouin frequency shift are monitored to discriminate strain and temperature. The longitudinal modes beat frequency is measured by observing the self-beating signals of the EDFL, while the Brillouin frequency shift is measured by monitoring the heterodyning signal of the BEFL. The simultaneous measurement errors of strain and temperature are within ± 25.8µÎµ and ± 0.8°C. The sensor is of simple structure and compact size.

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