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1.
ACS Appl Mater Interfaces ; 15(50): 58274-58285, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38051105

RESUMO

Colored radiative cooling (CRC) offers an attractive alternative for surface and space cooling, while preserving the aesthetics of an object. However, there has been no study on the CRC using phosphors in regard to vivid coloration, sophisticated performance investigation, retention of properties, functionality, and structural flexibility all at once. Thus, to manage the entire solar spectrum, a colored cooling structure comprising a near-infrared (NIR)-reflective bottom layer and a top colored layer with a phosphor-embedded polymer matrix is proposed. The structure is paintable, vividly colored, hydrophobic, and ultraviolet (UV) and water resistant. In the daytime outdoor measurement, the structure with red, orange, and yellow colors exhibited lower temperature than a control group using commercial white paint by 4.7 °C, 7.2 °C, and 7.4 °C, respectively. After precise theoretical and experimental time-tracing temperature validation, the CRC performance enhancement from NIR reflection and photoluminescence effects was thoroughly analyzed, and a temperature reduction of up to 16.1 °C was achieved for the orange-colored structure. Furthermore, experiments of hydrophobicity infusion and exposure to UV and deionized water verified the durability of the colored cooling structure. In addition, flexible-film-type colored cooling structures were demonstrated using different bottom reflective layers, such as a silver thin film and porous aluminum oxide particle-embedded poly(vinylidene fluoride-co-hexafluoropropylene), suggesting the potential applicability of these colored cooling structures for vivid-colored, functional, and durable CRC.

2.
Genes Dev ; 37(9-10): 383-397, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-37236670

RESUMO

DROSHA serves as a gatekeeper of the microRNA (miRNA) pathway by processing primary transcripts (pri-miRNAs). While the functions of structured domains of DROSHA have been well documented, the contribution of N-terminal proline-rich disordered domain (PRD) remains elusive. Here we show that the PRD promotes the processing of miRNA hairpins located within introns. We identified a DROSHA isoform (p140) lacking the PRD, which is produced by proteolytic cleavage. Small RNA sequencing revealed that p140 is significantly impaired in the maturation of intronic miRNAs. Consistently, our minigene constructs demonstrated that PRD enhances the processing of intronic hairpins, but not those in exons. Splice site mutations did not affect the PRD's enhancing effect on intronic constructs, suggesting that the PRD acts independently of splicing reaction by interacting with sequences residing within introns. The N-terminal regions from zebrafish and Xenopus DROSHA can replace the human counterpart, indicating functional conservation despite poor sequence alignment. Moreover, we found that rapidly evolving intronic miRNAs are generally more dependent on PRD than conserved ones, suggesting a role of PRD in miRNA evolution. Our study reveals a new layer of miRNA regulation mediated by a low-complexity disordered domain that senses the genomic contexts of miRNA loci.


Assuntos
MicroRNAs , Ribonuclease III , Animais , Humanos , Íntrons/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Prolina/genética , Prolina/metabolismo , Ribonuclease III/genética , Ribonuclease III/metabolismo , Processamento Pós-Transcricional do RNA , Peixe-Zebra
3.
Glob Chall ; 6(7): 2100118, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35860392

RESUMO

In this study, a different number of indium zinc oxide (IZO) interlayers are fabricated into Al2O3-based transparent resistive switching memory on a transparent indium tin oxide (ITO)/glass substrate at room temperature. Al2O3/IZO multilayer transparent memory has a transmittance of at least 65% in the wavelength range of 400-900 nm. In addition, the Al2O3/IZO multilayer transparent memory can achieve an electroforming voltage that is 35.7% lower than that of ITO/pure-Al2O3/IZO transparent memory. The fabricated Al2O3/IZO multilayer transparent memory exhibits typical bipolar resistive switching behavior, regardless of the number of IZO interlayers. Also, the fabricated Al2O3/IZO multilayer transparent memory has a low operating voltage within ±1.5 V. In addition, a flexible Al2O3/IZO multilayer transparent memory is fabricated using the same process on ITO-coated polyethylene terephthalate. The fabricated flexible transparent memory also maintains the resistive switching characteristics during the bending state.

4.
Medicina (Kaunas) ; 58(6)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35744021

RESUMO

Background and objective: This study aimed to investigate the estimated rate and risk of recurrence of uncomplicated diverticulitis (UCD) after the first episode through a meta-analysis. Methods: Eligible studies were searched and reviewed; 27 studies were included in this study. Subgroup analyses were performed, based on lesion location, medical treatment, follow-up period, and study location. Results: The estimated recurrence rate of UCD was 0.129 (95% confidence interval [CI] 0.102-0.162). The recurrence rates of the right-and left-sided colon were 0.092 (95% CI 27.063-0.133) and 0.153 (95% CI 0.104-0.218), respectively. The recurrence rate according to follow-up period was highest in the subgroup 1-2 years, compared with that of other subgroups. The recurrence rate of the Asian subgroup was significantly lower than that of the non-Asian subgroup (0.092, 95% CI 0.064-0.132 vs. 0.147, 95% CI 0.110-0.192; p = 0.043 in the meta-regression test). There were significant correlations between UCD recurrence and older age and higher body temperature. However, UCD recurrence was not significantly correlated with medications, such as antibiotics or anti-inflammatory drugs. Conclusions: In this study, detailed information on estimated recurrence rates of UCD was obtained. In addition, older age and higher body temperature may be risk factors for UCD recurrence after the first episode.


Assuntos
Doença Diverticular do Colo , Diverticulite , Diverticulite/terapia , Doença Diverticular do Colo/epidemiologia , Humanos , Recidiva , Fatores de Risco , Resultado do Tratamento
5.
Diagnostics (Basel) ; 12(3)2022 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-35328309

RESUMO

The study is aimed to evaluate the diagnostic and prognostic role of the immunohistochemical expression of the Caudal-type homeobox transcription factor 2 (CDX2) in colorectal cancers (CRCs) through a meta-analysis. By searching relevant databases, 38 articles were eligible to be included in this study. We extracted the information for CDX2 expression rates and the correlation between CDX2 expression and clinicopathological characteristics. The estimated rates of CDX2 expression were 0.882 [95% confidence interval (CI) 0.774−0.861] and 0.893 (95% CI 0.820−0.938) in primary and metastatic CRCs, respectively. Furthermore, based on their histologic subtype, CDX2 expression rates of adenocarcinoma and medullary carcinoma were 0.886 (95% CI 0.837−0.923) and 0.436 (95% CI 0.269−0.618), respectively. There was a significant difference in CDX2 expression rates between adenocarcinoma and medullary carcinoma in the meta-regression test (p < 0.001). In addition, CDX2 expression was significantly lower in CRCs with the BRAFV600E mutation than in CRCs without mutation. Patients with CDX2 expression had better overall and cancer-specific survival rates than those without CDX2 expression. Thus, CDX2 is a useful diagnostic and prognostic marker CRCs.

6.
Opt Express ; 29(20): 31364-31375, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615230

RESUMO

For the efficient radiative cooling of objects, coolers should emit heat within atmospheric transparent window and block heat absorption from the surrounding environments. Thus, selective emitters enable highly efficient cooling via engineered photonic structures such as metamaterials and multi-stacking structures. However, these structures require sophisticated fabrication processes and large quantities of materials, which can restrict mass-production. This study introduces an ultra-thin (∼1 µm) and near-unity selective emitter (UNSE) within the atmospheric window, which can be fabricated using simple and affordable process. The combination of infrared (IR) lossy layers and high index lossless layer enhances the resonance in the structure thus, the emissivity in long wavelength IR region increases to near-unity within a thickness of ∼1 µm.

7.
ACS Appl Mater Interfaces ; 13(18): 21119-21126, 2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-33926186

RESUMO

Passive daytime radiative cooling, which is a process that removes excess heat to cold space as an infinite heat sink, is an emerging technology for applications that require thermal control. Among the different structures of radiative coolers, multilayer- and photonic-structured radiative coolers that are composed of inorganic layers still need to be simple to fabricate. Herein, we describe the fabrication of a nanoparticle-mixture-based radiative cooler that exhibits highly selective infrared emission and low solar absorption. Al2O3, SiO2, and Si3N4 nanoparticles exhibit intrinsic absorption in parts of the atmospheric transparency window; facile one-step spin coating of a mixture of these nanoparticles generates a surface with selective infrared emission, which can provide a more powerful cooling effect compared to broadband emitters. The nanoparticle-based radiative cooler exhibits an extremely low solar absorption of 4% and a highly selective emissivity of 88.7% within the atmospheric transparency window owing to the synergy of the optical properties of the material. The nanoparticle mixture radiative cooler produces subambient cooling of 2.8 °C for surface cooling and 1.0 °C for space cooling, whereas the Ag film exhibits an above-ambient cooling of 1.1 °C for surface cooling and 3.4 °C for space cooling under direct sunlight.

8.
Small ; 17(20): e2006558, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33864345

RESUMO

In this study, a high-performance photoanode based on 3D periodic, micropillar-structured fluorine-doped tin oxide (FTO-MP) deposited with BiVO4 is fabricated using the patterned FTO by direct printing and spray pyrolysis, followed by the deposition of BiVO4 by sputtering and V ion heat-treatment on the patterned FTO. The FTO-MP enables light scattering owing to its 3D periodic structure and increases the light absorption efficiency. In addition, the high electron mobility of FTO and enlarged surface area of FTO-MP enhance the separation efficiency. Due to the combination of these enhancing strategies, the photocurrent density of micropillar-patterned BiVO4 at 1.23 VRHE reached 2.97 mA cm-2 , which is 67.8% higher than that of flat BiVO4 . The results suggest that the efficiency can increase significantly using the patterned FTO fabricated by an inexpensive and simple process (i.e., direct printing and spray pyrolysis), thereby indicating a new strategy for the enhancement of efficiency in various energy fields.

9.
ACS Appl Mater Interfaces ; 12(52): 57832-57839, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33345542

RESUMO

Passive daytime radiative cooling provides cooling without energy input. This method is eco-friendly, which is beneficial, considering the increasing problems of global warming and urban heat islands. A poly(vinylidene fluoride) (PVDF) and polyurethane acrylate (PUA) matte white coating was prepared via photo-initiated free-radical polymerization. The porous polymeric coating without a metal-reflective layer exhibited an average emissivity of 0.9333 in the atmospheric window and an average solar reflectance of 0.9336 in the direct AM1.5 solar spectrum (888 W m-2 in the 0.3-2.5 µm region). The radiative cooling power of the fabricated radiative cooler with a thickness of 518 µm was 94.2 W m-2. Furthermore, the radiative cooler demonstrated radiative cooling performance during both daytime and nighttime in Seoul, Korea, and Chiang Mai, Thailand. The PVDF/PUA matte white coating without a silver reflector can prevent solar absorption caused by the oxidation of silver and reduce the light pollution caused by the metallic film because of the antiglare surface of the matte coating.

10.
ACS Appl Mater Interfaces ; 12(49): 54763-54772, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33251797

RESUMO

In this study, multifunctional light-emitting and passive radiative cooling (LEPC) materials and devices are designed by embedding chemically designed perovskite nanocrystals (NCs) into the radiative polymer layer. Lead halide perovskite NCs are chosen as the light-emitting material, owing to their high photon radiation rate and low phonon generation. To integrate the perovskite NCs into the radiative polymer layers, a surface passivation is achieved by coating the NCs with silica. The silica shell synergistically improves the chemical stability and cooling efficiency. Both outdoor experimental and simulation results demonstrate that the fabricated LEPC devices show better cooling performance than conventional cooling devices. The LEPC devices are easily patterned by utilizing pixelating, assembling, and simple cutting or drawing techniques with the LEPC materials. This study also demonstrates the potential applications of these materials as components of smart building systems, in smart window displays, or for anticounterfeiting cooling systems, thus proving the practicality of these multifunctional LEPC devices.

11.
Nat Commun ; 11(1): 6033, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33247115

RESUMO

MicroRNAs (miRNAs) are short (19-24 nt) non-coding RNAs that suppress the expression of protein coding genes at the post-transcriptional level. Differential expression profiles of miRNAs across a range of diseases have emerged as powerful biomarkers, making a reliable yet rapid profiling technique for miRNAs potentially essential in clinics. Here, we report an amplification-free multi-color single-molecule imaging technique that can profile purified endogenous miRNAs with high sensitivity, specificity, and reliability. Compared to previously reported techniques, our technique can discriminate single base mismatches and single-nucleotide 3'-tailing with low false positive rates regardless of their positions on miRNA. By preloading probes in Thermus thermophilus Argonaute (TtAgo), miRNAs detection speed is accelerated by more than 20 times. Finally, by utilizing the well-conserved linearity between single-molecule spot numbers and the target miRNA concentrations, the absolute average copy numbers of endogenous miRNA species in a single cell can be estimated. Thus our technique, Ago-FISH (Argonaute-based Fluorescence In Situ Hybridization), provides a reliable way to accurately profile various endogenous miRNAs on a single miRNA sensing chip.


Assuntos
MicroRNAs/análise , MicroRNAs/isolamento & purificação , Sequência de Bases , Linhagem Celular , Humanos , Thermus/genética
12.
Adv Sci (Weinh) ; 7(19): 2001577, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33042765

RESUMO

Daytime radiative cooling serving as a method to pump heat from objects on Earth to cold outer space is an attractive cooling option that does not require any energy input. Among radiative cooler structures, the multilayer- or photonic-structured radiative cooler, composed of inorganic materials, remains one of the most complicated structures to fabricate. In this study, transparent sapphire-substrate-based radiative coolers comprising a simple structure and selective emitter-like optical characteristics are proposed. Utilizing the intrinsic optical properties of the sapphire substrate and adopting additional IR emissive layers, such as those composed of silicon nitride thin film or aluminum oxide nanoparticles, high-performance radiative coolers can be fabricated with a low mean absorptivity (3-4%) at 0.3-2.5 µm and a high mean emissivity of over 90% at 8-13 µm. Experiments show that the fabricated radiative coolers reach temperature drops of ≈10 °C in the daytime. From the theoretical calculations of radiative cooling performance, the sapphire-substrate-based radiative coolers demonstrate a net cooling power as high as 100 Wm-2.

13.
ACS Appl Mater Interfaces ; 12(7): 8073-8081, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31990166

RESUMO

Daytime radiative coolers are used to pump excess heat from a target object into a cold exterior space without energy consumption. Radiative coolers have become attractive cooling options. In this study, a daytime radiative cooler was designed to have a selective emissive property of electromagnetic waves in the atmospheric transparency window of 8-13 µm and preserve low solar absorption for enhancing radiative cooling performance. The proposed daytime radiative cooler has a simple multilayer structure of inorganic materials, namely, Al2O3, Si3N4, and SiO2, and exhibits high emission in the 8-13 µm region. Through a particle swarm optimization method, which is based on an evolutionary algorithm, the stacking sequence and thickness of each layer were optimized to maximize emissions in the 8-13 µm region and minimize the cooling temperature. The average value of emissivity of the fabricated inorganic radiative cooler in the 8-13 µm range was 87%, and its average absorptivity in the solar spectral region (0.3-2.5 µm) was 5.2%. The fabricated inorganic radiative cooler was experimentally applied for daytime radiative cooling. The inorganic radiative cooler can reduce the temperature by up to 8.2 °C compared to the inner ambient temperature during the daytime under direct sunlight.

14.
Nanotechnology ; 31(14): 144003, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31891918

RESUMO

A phosphor substrate converts a moderate amount of blue light to green light to produce white light. In this study, we have successfully demonstrated the enhancement of the light extraction efficiency of YAG:Ce phosphor substrate using a simple imprint process. Spin-on-glass materials were used to fabricate a pattern on the surface of a phosphor substrate, and nano- and micro-scale patterns were formed to test the performance according to the size of pattern. The light extraction efficiency of the phosphor substrate with a micro-cone pattern increased by 33.2% compared with the flat phosphor substrate.

15.
Nanotechnology ; 31(20): 204003, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31995544

RESUMO

Among many candidates for photoanode materials of photoelectrochemical (PEC) cell, nanostructured tungsten trioxide (WO3) is regarded as one of the most promising materials due to its superior electrical properties and adequate bandgap (∼2.8 eV) and band edge position. WO3 nanoflakes (WO3 NFs), which have merits on its high surface area and crystallinity, have been actively studied for this manner but solar-to-hydrogen efficiency of WO3 NFs based photoanode is still not sufficient both in light absorption and charge separation. Plasmon-induced enhancement using Au nanoparticles is excellent approach for both the efficiency of light absorption and charge separation of WO3. However, it still needs optimization on its amount, shape, coverage, and etc. Here, we synthesized WO3 NFs by solvothermal growth and decorated gold nanoparticles on these nanoflakes by e-beam evaporation and rapid thermal annealing process in a row. By this process, a large-area AuNPs/WO3 nanocomposite structure with various size, interparticle distance, and coverage of AuNPs were fabricated. These AuNPs/WO3 NFs type photoanode achieve high light absorption both in UV and visible range and consequently higher photocurrent density. The optimized AuNPs/WO3 nanocomposite photoanode exhibits 1.01 mA cm-2 of photocurrent density, which is increased to 19.8% compared with bare WO3 nanoflakes. Field emission-scanning electron microscope, x-ray diffraction, UV-vis spectrometer analysis were measured to analyze the morphology and crystallinity and relationship between structure and PEC performance.

16.
Nanoscale ; 10(46): 21696-21702, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30431043

RESUMO

ZnO-based hierarchical structures including nanoparticles (NPs), nanorods (NRs) and nanoflowers (NFs) on a 3D-printed backbone were effectively fabricated via the combination of the fused deposition modelling (FDM) 3D-printing technique and hydrothermal reaction. The photocatalytic performance of the ZnO-based hierarchical structures on the 3D-backbone was verified via the degradation of the organic pollutant methylene blue, which was monitored by UV-vis spectroscopy. The new photocatalytic architectures used in this investigation give an effective approach and wide applicability to overcome the limitation of photocatalysts such as secondary removal photocatalyst processes.

17.
Restor Neurol Neurosci ; 23(1): 11-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15846028

RESUMO

PURPOSE: This study examined whether the degree of impairment of diffusion anisotrophy in the early stages of a stroke can predict the motor function outcome. METHODS: Thirty-one hemiplegic stroke patients were enrolled to this study. Diffusion anisotropy was measured by determining fractional anisotropy (FA) in the two ROIs (region of interests) at corona radiata (CR) and in the posterior limb of internal capsule (IC) during the early stages of stoke (average 7.9 days after stroke onset) and compared with motor outcome of the affected hand 3 months after stroke onset. RESULTS: Both ROIs (CR or IC) and lesion types (hemorrhage or infarction) did not have significant effect on the SBFA (symmetry of bilateral FA) and dMRC (medical research council score improvement), either. Patients with greater initial MRC score had significantly greater SBFA and dMRC. The regression equation between the dMRC (Y axis) and the SBFA (X axis) was semi-linear and significant (P < 0.05); for CR group, Y = 3.296 - 0.1192X + 0.0015X2; for IC group, Y = 2.342 - 0.0533X +0.0007(2). The regression lines had 'threshold points' where a minute SBFA change would make a steep increase in dMRC. CONCLUSION: The degree of impairment in diffusion anisotropy during the early stages of stroke appears to have the potential to predict motor outcome.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Destreza Motora/fisiologia , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Análise de Variância , Feminino , Humanos , Cápsula Interna/metabolismo , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Acidente Vascular Cerebral/metabolismo , Fatores de Tempo
18.
Neuroreport ; 14(10): 1329-32, 2003 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-12876467

RESUMO

This fMRI study was undertaken to test whether the pathophysiological mechanism of mirror movements in hemiparetic stroke patients involves activation of the unaffected motor cortex. We studied 16 control subjects and 51 stroke patients. fMRI was performed at 1.5 T using a finger flexion-extension movement paradigm. The incidence of bilateral primary sensorimotor cortex activation was significantly increased during movements of the affected hand of stroke patients who showed mirror movements. Moreover, the incidence of bilateral primary sensorimotor cortex activation increased with the severity of mirror movements and primary sensorimotor cortex was activated bilaterally in all patients who showed sustained mirror movements. We conclude that the motor cortex activation on the non-stroke side is associated with mirror movements and is correlated with the severity of mirror movements. It seems that the pathophysiological mechanism of sustained mirror movements in stroke patients involves the unaffected motor cortex.


Assuntos
Lateralidade Funcional/fisiologia , Imageamento por Ressonância Magnética/métodos , Córtex Motor/fisiopatologia , Movimento/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Mapeamento Encefálico , Feminino , Mãos/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Motor/patologia , Desempenho Psicomotor/fisiologia
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