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1.
J Comput Assist Tomogr ; 48(1): 137-142, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37531643

RESUMEN

OBJECTIVE: To investigate the utility of texture analysis in detecting osseous changes associated with hyperparathyroidism on neck CT examinations compared with control patients and to explore the best regions in the head and neck to evaluate changes in the trabecular architecture secondary to hyperparathyroidism. METHODS: Patients with hyperparathyroidism who underwent a 4D CT of the neck with contrast were included in this study. Age-matched control patients with no history of hyperparathyroidism who underwent a contrast-enhanced neck CT were also included. Mandibular condyles, bilateral mandibular bodies, the body of the C4 vertebra, the manubrium of the sternum, and bilateral clavicular heads were selected for analysis, and oval-shaped regions of interest were manually placed. These segmented areas were imported into an in-house developed texture analysis program, and 41 texture analysis features were extracted. A mixed linear regression model was used to compare differences in the texture analysis features contoured at each of the osseous structures between patients with hyperparathyroidism and age-matched control patients. RESULTS: A total of 30 patients with hyperparathyroidism and 30 age-matched control patients were included in this study. Statistically significant differences in texture features between patients with hyperparathyroidism and control patients in all 8 investigated osseous regions. The sternum showed the greatest number of texture features with statistically significant differences between these groups. CONCLUSIONS: Some CT texture features demonstrated statistically significant differences between patients with hyperparathyroidism and control patients. The results suggest that texture features may discriminate changes in the osseous architecture of the head and neck in patients with hyperparathyroidism.


Asunto(s)
Hiperparatiroidismo Primario , Humanos , Hiperparatiroidismo Primario/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada Cuatridimensional
2.
Small ; 15(50): e1905209, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31631563

RESUMEN

The bidirectional transport of nanoparticles and biological cells is of great significance in efficient biological assays and precision cell screening, and can be achieved with optical conveyor belts in a noncontact and noninvasive manner. However, implantation of these belts into biological systems can present significant challenges owing to the incompatibility of the artificial materials. In this work, an optical conveyor belt assembled from natural biological cells is proposed. The diameter of the belt (500 nm) is smaller than the laser wavelength (980 nm) and, therefore, the evanescent wave stably traps the nanoparticles and cells on the belt surface. By adjusting the relative power of the lasers injected into the belt, the particles or cells can be bidirectionally transported along the bio-conveyor belt. The experimental results are numerically interpreted and the transport velocities are investigated based on simulations. Further experiments show that the bio-conveyor belt can also be assembled with mammalian cells and then applied to dynamic cell transport in vivo. The bio-conveyor belt might provide a noninvasive and biocompatible tool for biomedical assays, drug delivery, and biological nanoarchitectonics.


Asunto(s)
Células/metabolismo , Nanopartículas/química , Adulto , Animales , Transporte Biológico , Simulación por Computador , Escherichia coli/metabolismo , Humanos , Masculino , Poliestirenos/metabolismo , Pez Cebra
3.
Theor Appl Genet ; 132(6): 1761-1775, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30830267

RESUMEN

KEY MESSAGE: QTL mapping for fiber-related traits and elucidation of a stable and novel QTL affecting seed lignin content, cellulose content and seed oil content. Dissection of the genetic networks for fiber biosynthesis is important for improving the seed oil content and meal value of Brassica napus. In this study, the genetic basis of seed fiber biosynthesis in B. napus was investigated via quantitative trait locus (QTL) analysis using a doubled haploid population derived from 'KenC-8' crossed with 'N53-2.' Seed lignin content (LC), cellulose content (CC) and hemicellulose content (HC) were significantly negatively correlated with seed oil content (OC). Co-localization QTLs among LC, CC, HC and OC on A09 were found with contributions ranging from 9.87 to 48.50%. Seven co-localization QTLs involved in the fiber component and OC were further verified by bulked segregant analysis (BSA). The unique QTL uqA9-12 might be a real and new QTL that was commonly identified by QTL mapping and BSA and simultaneously affected LC, CC and OC with opposite additive effects. A potential regulatory network controlling seed fiber biosynthesis was constructed to dissect the complex mechanism of seed fiber and oil accumulation, and numerous candidate genes were identified in the fiber-related QTL regions. These results provided an enrichment of QTLs and potential candidates for fiber biosynthesis, as well as useful new information for understanding the complex genetic mechanism underlying rapeseed seed fiber accumulation.


Asunto(s)
Brassica napus/genética , Celulosa/análisis , Redes Reguladoras de Genes , Genoma de Planta , Proteínas de Plantas/metabolismo , Sitios de Carácter Cuantitativo , Semillas/metabolismo , Brassica napus/metabolismo , Ligamiento Genético , Fenotipo , Proteínas de Plantas/genética , Semillas/química
4.
Artículo en Inglés | MEDLINE | ID: mdl-38954243

RESUMEN

Oral microorganisms are closely related to oral health, the occurrence of some oral diseases is associated with changes in the oral microbiota, and many studies have demonstrated that traditional smoking can affect the oral microbial community. However, due to the short time since the emergence of e-cigarettes, fewer studies are comparing oral microorganisms for users of e-cigarettes versus cigarettes. We collected saliva from 40 non-smokers (NS), 46 traditional cigarette smokers (TS), and 27 e-cigarette consumers (EC), aged between 18 and 35 years. We performed 16S rRNA gene sequencing on the saliva samples collected to study the effects of e-cigarettes versus traditional cigarettes on the oral microbiome. The results showed that compared with the NS group, the alpha diversity of oral flora in saliva was altered in the TS group, with no significant change in the e-cigarette group. Compared with the NS and EC groups, the relative abundance of Actinomyces and Prevotella was increased in the TS group. However, compared with the NS and TS groups, the relative abundance of Veillonella was increased, and the relative abundance of Porphyromonas and Peptostreptococcus was decreased in the EC group. These results showed that both e-cigarettes and traditional cigarettes could alter the structure and composition of oral microbiota. The use of traditional cigarettes promotes the growth of some anaerobic bacteria, which may contribute to dental decay and bad breath over time. E-cigarettes have a different effect on the structure and composition of the oral microbial community compared to conventional cigarettes. In order to better understand the effects of e-cigarettes and traditional cigarettes on users' mouths, future studies will investigate the relationship between diseases such as dental caries and periodontitis and changes in oral microbial species levels.

5.
Toxicol In Vitro ; : 105605, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37164182

RESUMEN

Smoking increases the risk of a number of diseases, including cardiovascular, oral and lung diseases. E-cigarettes are gaining popularity among young people as an alternative to cigarettes, but there is debate over whether they are less harmful to the mouth than e-cigarettes. In this study, human gingival epithelial cells (HGECs) were treated with four commercially available e-cigarette aerosol condensates (ECAC) or commercially available generic cigarette smoke condensates (CSC) with different nicotine concentrations. Cell viability was determined by MTT assay. Cell apoptosis was observed by acridine orange (AO) and Hoechst33258 staining. The levels of type I collagen, matrix metalloproteinase (MMP-1, MMP-3), cyclooxygenase 2 and inflammatory factors were detected by ELISA and RT-PCR. Finally, ROS levels were analyzed by ROS staining. The different effects of CSC and ECAC on HGECs were compared. The results showed that higher nicotine concentration of CS significantly reduced the activity of HGECs. By contrast, all ECAC had no significant effect. The levels of matrix metalloproteinase, COX-2, and inflammatory factors were higher in HGECs treated with CSC than those treated with ECAC. In contrast, the level of type I collagen was higher in HGECs treated with ECAC than those treated with CSC. In conclusion, all four flavors of e-cigarettes were less toxic to HGE cells than tobacco, but further clinical studies are needed to determine whether e-cigarettes are less harmful to oral health than conventional cigarettes.

6.
ACS Omega ; 8(12): 10919-10929, 2023 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-37008119

RESUMEN

Smoking increases the risk of a number of diseases, including cardiovascular, oral, and lung diseases. E-cigarettes are gaining popularity among young people as an alternative to cigarettes, but there is debate over whether they are less harmful to the mouth than e-cigarettes. In this study, human gingival epithelial cells (HGECs) were treated with four commercially available e-cigarette aerosol condensates (ECAC) or commercially available generic cigarette smoke condensates (CSC) with different nicotine concentrations. Cell viability was determined by MTT assay. Cell apoptosis was observed by acridine orange (AO) and Hoechst33258 staining. The levels of type I collagen, matrix metalloproteinase (MMP-1, MMP-3), cyclooxygenase 2, and inflammatory factors were detected by ELISA and RT-PCR. Finally, ROS levels were analyzed by ROS staining. The different effects of CSC and ECAC on HGECs were compared. The results showed that higher nicotine concentration of CS significantly reduced the activity of HGECs. By contrast, all ECAC had no significant effect. The levels of matrix metalloproteinase, COX-2, and inflammatory factors were higher in HGECs treated with CSC than those treated with ECAC. In contrast, the level of type I collagen was higher in HGECs treated with ECAC than those treated with CSC. In conclusion, all four flavors of e-cigarettes were less toxic to HGE cells than tobacco, but further clinical studies are needed to determine whether e-cigarettes are less harmful to oral health than conventional cigarettes.

7.
Opt Express ; 20(2): 1292-300, 2012 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-22274474

RESUMEN

We report a separation of two different size particles in fluidic flow by an optical fiber. With a light of 1.55 µm launched into the fiber, particles in stationary water were massively trapped and assembled around the fiber by a negative photophoretic force. By introducing a fluidic flow, the assembled particles were separated into two different downstream positions according to their sizes by the negative photophoretic force and the dragging force acted on the particles. The intensity distribution of light leaked from the fiber and the asymmetry factor of energy distribution have been analysed as crucial factors in this separation. Poly(methyl methacrylate) particles (5-/10-µm diameter), SiO(2) particles (2.08-/5.65-µm diameter), and SiO(2) particles (2.08-µm diameter) mixed with yeast cells were used to demonstrate the effectiveness of the separation. The separation mechanism has also been numerical simulated and theoretical interpreted.


Asunto(s)
Bacterias/aislamiento & purificación , Tecnología de Fibra Óptica/métodos , Microfluídica/instrumentación , Microesferas , Pinzas Ópticas , Diseño de Equipo , Luz , Microscopía/instrumentación , Modelos Teóricos , Tamaño de la Partícula , Polimetil Metacrilato , Dióxido de Silicio
8.
Oral Radiol ; 38(3): 315-324, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34327595

RESUMEN

OBJECTIVES: The purpose of this study was to investigate computed tomography (CT) texture features of mucosal thickening of maxillary sinus mucosa to differentiate odontogenic maxillary sinusitis (OMS) from non-odontogenic maxillary sinusitis (NOMS). METHODS: Eighteen OMS patients and age- and gender-matched 18 NOMS patients who underwent sinus CT were retrospectively reviewed. OMS patients were identified by histopathological examination of tissues excised at surgery combined with CT imaging findings. Patients with mucosal thickening in the maxillary sinus without apical periodontitis or advanced periodontal bone loss near the maxillary sinus on CT were defined as NOMS. Patients with thin mucosal thickening (< 10 mm), cyst, tumor, post-operative deformity, severe metal artifact precluding visualization of the maxillary sinus, and age younger than 20 years were excluded. CT texture features of the mucosal thickening were analyzed using an in-house developed Matlab-based texture analysis program. Forty-five texture features were extracted from each segmented volume. The results were tested with the Mann-Whitney U test. RESULTS: Six histogram features (mean, median, standard deviation, entropy, geometric mean, harmonic mean) and two gray-level co-occurrence matrix features (entropy, correlation) showed significant differences between OMS and NOMS patients. CONCLUSIONS: CT texture analysis revealed the quantitative differences between OMS and NOMS. The texture features can serve as a quantitative indicator of maxillary sinusitis to differentiate between OMS and NOMS and help prevent incorrect treatment choices.


Asunto(s)
Sinusitis Maxilar , Adulto , Humanos , Seno Maxilar/patología , Sinusitis Maxilar/diagnóstico por imagen , Sinusitis Maxilar/etiología , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/efectos adversos , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
9.
Opt Express ; 19(14): 13285-90, 2011 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-21747483

RESUMEN

Targeted drug delivery and controllable release are particularly beneficial in medical therapy. This work provides a demonstration of nanoparticles targeted delivery and controllable release using a defect-decorated optical nanofiber (NF). By using the NF, polystyrene particles (PSs) (713-nm diameter) suspended in water were successfully trapped, then delivered along the NF at an average velocity of 4.8 µm/s with the assistance of a laser beam of 980-nm wavelength at an optical power of 39 mW, and finally, assembled at the defect. Subsequently, by turning off the optical power, 90% of the assembled PSs can be released in 30 s. This method would be useful in targeted drug delivery and controllable release, and provide potential applications in targeted therapy.


Asunto(s)
Preparaciones de Acción Retardada/química , Tecnología de Fibra Óptica/métodos , Nanocápsulas/química , Nanocápsulas/ultraestructura , Poliestirenos/química , Ensayo de Materiales , Tamaño de la Partícula
10.
Eur J Radiol ; 116: 212-218, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31153568

RESUMEN

OBJECTIVES: To investigate the use of texture analysis for the detection of osteoporosis on noncontrast head CTs, and to explore optimal sampling regions within the craniofacial bones. METHODS: In this IRB-approved, retrospective study, the clivus, bilateral sphenoid triangles and mandibular condyles were manually segmented on each noncontrast head CT, and 41 textures features were extracted from 29 patients with normal bone density (NBD); and 29 patients with osteoporosis. Basic descriptive statistics including a false discovery rate correction were performed to evaluate for differences in texture features between the cohorts. RESULS: Sixteen texture features demonstrated significant differences (P < 0.01) between NBD and osteoporosis in the clivus including 4 histogram features, 2 gray-level co-occurrence matrix features, 8 gray-level run-length features and 2 Law's features. Nineteen texture features including 9 histogram features, 1 GLCM features, 2 GLRL features, 5 Law's features and 2 GLGM features demonstrated statistically significant differences in both sides of the sphenoid triangles. A total 24 texture features demonstrated statistically significant differences between normal BMD and osteoporosis in the left sphenoid and a total of 31 texture features in the left condyle. Furthermore, a total of 22 texture features including 6 histogram features, 3 GLCM features, 9 GLRL features, 2 Law's features and 2 GLGM features demonstrated statistically significant differences in both sides of the mandibular condyles. CONCLUSION: The results of this investigation suggest that specific texture analysis features derived from regions of interest placed within multiple sites within the skull base and maxillofacial bones can distinguish between patients with normal bone mineral density compared to those with osteoporosis. This study demonstrates the potential utility of a texture analysis for identification of osteoporosis on head CT, which may help identify patients who have not undergone screening with traditional DXA.


Asunto(s)
Densidad Ósea/fisiología , Osteoporosis/fisiopatología , Anciano , Anciano de 80 o más Años , Huesos Faciales/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
11.
Eur J Radiol ; 120: 108654, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31539792

RESUMEN

PURPOSE: Cystic and cystic-appearing odontogenic lesions of the jaw may appear similar on CT imaging. Accurate diagnosis is often difficult although the relationship of the lesion to the tooth root or crown may offer a clue to the etiology. The purpose of this study was to evaluate CT texture analysis as an aid in differentiating cystic and cystic-appearing odontogenic lesions of the jaw. METHODS: This was an IRB-approved retrospective study including 42 pathology-proven dentigerous cysts, 37 odontogenic keratocysts, and 19 ameloblastomas. Each lesion was manually segmented on axial CT images, and textural features were analyzed using an in-house-developed Matlab-based texture analysis program that extracted 47 texture features from each segmented volume. Statistical analysis was performed comparing all pairs of the three types of lesions. RESULTS: Pairwise analysis revealed that nine histogram features, one GLCM feature, three GLRL features, two Laws features, four GLGM features and two Chi-square features showed significant differences between dentigerous cysts and odontogenic keratocysts. Four histogram features and one Chi-square feature showed significant differences between odontogenic keratocysts and ameloblastomas. Two histogram features showed significant differences between dentigerous cysts and ameloblastomas. CONCLUSIONS: CT texture analysis may be useful as a noninvasive method to obtain additional quantitative information to differentiate cystic and cystic-appearing odontogenic lesions of the jaw.


Asunto(s)
Ameloblastoma/diagnóstico por imagen , Neoplasias Maxilomandibulares/diagnóstico por imagen , Quistes Odontogénicos/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ameloblastoma/patología , Niño , Quiste Dentígero/diagnóstico por imagen , Quiste Dentígero/patología , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Maxilomandibulares/patología , Masculino , Persona de Mediana Edad , Quistes Odontogénicos/patología , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
12.
Opt Express ; 16(14): 10815-22, 2008 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-18607497

RESUMEN

We report flexible and elastic enough nanofibers with diameters down to 60 nm and lengths up to 500 mm, fabricated by one-step drawing process from molten poly(trimethylene terephthalate) (PTT), exhibiting high surface smoothness and length uniformity. A series of ultracompact devices (such as optical beam splitters, couplers, rings, resonators, and tweezer/scissor-shaped structures) and nanophotonic device arrays have been assembled by the PTT nanofibers. Quantitative studies demonstrate that the PTT nanofibers/nanofiber devices exhibit good guiding properties with low optical loss from visible to near infrared region. The results suggest that the PTT nanophotonic fibers/wires would be promising candidates in constructing miniaturized photonic devices and ultracompact photonic integrated circuits (PICs), and a one-step drawing as an alternative to the standard optical bench technique.


Asunto(s)
Nanotecnología/métodos , Nanotubos/química , Pinzas Ópticas , Óptica y Fotónica , Tereftalatos Polietilenos/química , Cristalización , Diseño de Equipo , Luz , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Fotones
13.
Chemosphere ; 155: 109-114, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27108368

RESUMEN

The reproductive toxicity of fluoride has become a major concern in the world. Fluoride can decrease the abilities of sperm capacitation, hyperactivation, chemotaxis, acrosome reaction and fertilization, but the studies on the responses of sperm small noncoding RNAs (sncRNAs), especially miRNAs, to fluoride exposure are lacking. miRNAs are demonstrated to influence sperm quality and male fertility by regulating gene expression at post-transcriptional levels or translational repression. The objective of this study is to analyze miRNA profiling in sperm of mice administrated with 25 and 100 mg L(-1) sodium fluoride (NaF) for 60 d using high-throughput sequencing technology. Along with reduced sperm concentration, survival, motility, and mitochondrial membrane potential, 31 differentially expressed known miRNAs were identified in fluoride groups, compared with the control group. 671 predicted target genes against the 16 altered miRNAs were mainly involved in protease inhibitor activity, apoptosis, ubiquitin mediated proteolysis, and signaling pathways of calcium, JAK-STAT, MAPK, p53, Wnt, which were proved to be directly related to sperm quality. These findings suggested that the altered sperm miRNAs could be potential biomarkers for fluoride reproductive toxicity.


Asunto(s)
Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , MicroARNs/metabolismo , Fluoruro de Sodio/toxicidad , Espermatozoides/efectos de los fármacos , Animales , Fertilización , Humanos , Masculino , Ratones , MicroARNs/genética , Recuento de Espermatozoides , Espermatozoides/metabolismo
14.
Sci Rep ; 3: 1674, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23591750

RESUMEN

Nanoscale wavelength-converted optical components are promising components for communication and optical information processing in integrated photonic system. In this work, we report a facile strategy for realizing continuously tunable wavelength-converted wave-guiding in dye-doped nanofibers. The nanofibers with diameters of 200-800 nm have an absorption coefficient of about 80 cm(-1) and a self-absorption coefficient of about 30 cm(-1), and exhibit relatively high PL efficiency and high photobleaching resistance under an optical pump. By launching the pump light into the nanofibers, the excited light in the nanofibers got self-absorption and reemitted at a longer wavelength, resulting in a gradual wavelength conversion during propagation. On the basis of this wavelength-converted wave-guiding, nanoscale wavelength-converted splitters were demonstrated by assembling the nanofibers into crossed structures. We believe that the dye-doped nanofibers would bring new exciting opportunities in developing new wavelength-converted optical components for nanophotonic device integration.


Asunto(s)
Colorantes/química , Tecnología de Fibra Óptica/instrumentación , Nanopartículas/química , Nanopartículas/ultraestructura , Polímeros/química , Resonancia por Plasmón de Superficie/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Ensayo de Materiales , Dispersión de Radiación
15.
Water Res ; 46(8): 2535-44, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22386328

RESUMEN

The use of turbulence promoter can effectively enhance the permeate flux in crossflow microfiltration (CFMF) of particulate suspensions. Flux enhancement which is generally attributed to the reduction in cake thickness, however, has still not been clearly understood. In this study, the effects of turbulence promoter on cake properties (thickness, porosity and particle size) were investigated during CFMF of calcium carbonate suspension. It indicates that turbulence promoter has important effects on cake properties that directly affect the cake resistance. The significant reduction in thickness and slight increase in porosity are positive to reduce the cake resistance. The remarkable decrease in particle size is the negative effect due to the increased specific resistance of a cake. As a whole, the overall cake resistance is still diminished by turbulence promoter and therefore permeate flux is improved. The theoretical calculation of cake resistance shows a good consistence with the experimental result. The cake properties in both cases (using a turbulence promoter or not) almost exhibit the similar trends under various operating conditions. Differently, the use of turbulence promoter can greatly alleviate the effects of transmembrane pressure or feed concentration on growth of cake layer and intensify the effects of inlet velocity on diminishing the particle deposition.


Asunto(s)
Incrustaciones Biológicas , Material Particulado/química , Ultrafiltración/instrumentación , Ultrafiltración/métodos , Cerámica/química , Membranas Artificiales , Nefelometría y Turbidimetría , Tamaño de la Partícula , Permeabilidad , Porosidad , Presión , Suspensiones , Factores de Tiempo
16.
ACS Appl Mater Interfaces ; 4(8): 4106-12, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22775061

RESUMEN

The oxidation-resistant acidic resins are of great importance for the catalytic oxidation systems. In this paper, the oxidatively stable acidic resins are obtained from the cation ion exchange resins (CIERs) through the thermal treatment in N(2) atmosphere. The structure and properties of the thermally treated CIERs were characterized by chemical analysis, Fourier transform infrared (FT-IR) spectra, acid capacity measurement and scanning electron microscope (SEM). The thermally treated CIERs possess high acid capacity up to 4.09 mmol g(-1). A partial carbonization is observed in the thermal treatment process of CIERs, but the morphology of resin spheres maintains well. The as-prepared CIERs are used as solid acids to assist the hydrogen peroxide oxidation of cyclohexene to adipic acid (ADA) with tungstic acid as the catalyst precursor. The improved yields of ADA in the recycling reaction are obtained in the presence of acidic CIERs. Meanwhile, the unproductive decomposition of H(2)O(2) is effectively suppressed. The high yields of ADA (about 81%) are kept by the thermally treated CIERs even after the fifth cycle. The thermally treated CIERs exhibit excellent acid-catalytic performance and possess remarkable oxidation-resistant capability.


Asunto(s)
Adipatos/química , Carbono/química , Oxígeno/química , Polímeros/química , Ácidos , Catálisis , Ciclohexenos/química , Calor , Peróxido de Hidrógeno/química , Microscopía Electrónica de Rastreo/métodos , Modelos Químicos , Nitrógeno/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos
17.
ACS Nano ; 5(3): 2020-5, 2011 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-21306126

RESUMEN

We report a number of crossed nanofiber structures for full-color micro/nanodisplays, which were formed by assembling flexible poly(trimethylene terephthalate) (PTT) nanofibers under an optical microscope with the assistance of micromanipulators. The color pixels of the displays consist of micro/nanometer sized color spots in a radius of 300-1500 nm, which were realized through crossed junctions of the PTT nanofibers. The colors of the spots were tuned by changing the power ratios of the launched red, green, and blue lights. We further present a new way to develop white light illumination by combination of red, green, and blue lights with assembly techniques and low production costs.


Asunto(s)
Color , Iluminación/instrumentación , Nanoestructuras/química , Nanoestructuras/ultraestructura , Tereftalatos Polietilenos/síntesis química , Diseño de Equipo , Análisis de Falla de Equipo , Ensayo de Materiales , Tamaño de la Partícula
18.
ACS Nano ; 3(10): 3110-4, 2009 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-19746952

RESUMEN

We report a tunable refractive index sensor with ultracompact structure in a 2 x 2 poly(trimethylene terephthalate) (PTT) nanowire coupling splitter assembled by twisting two flexible PTT nanowires. The sensor consists of two input branches, a twisted coupling region, and two output branches. The changes of optical power caused due to variations in the surrounding medium around the twisted coupling region were measured in the output branches. The highest measured sensitivity of the sensor is 26.96 mW/RIU (refractive index unit) and the maximum detection limit on refractive index change is 1.85 x 10(-7). The average tunabilities observed are 1.2 mW per RIU per twisted turn and 1.8 mW per RIU per 5 degrees branching angle change.


Asunto(s)
Técnicas de Química Analítica/instrumentación , Nanocables/química , Tereftalatos Polietilenos/química , Microscopía , Rotación
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