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1.
Opt Lett ; 49(16): 4753-4754, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39146152

RESUMEN

We present an erratum to our Letter [Opt. Lett.48, 6344 (2023)10.1364/OL.510237]. This erratum corrects the error of Figs. 3(b) and 4(b) made via incorrect scaling in the horizontal axes. The corrections have no influence on the main text and conclusions of the original Letter.

2.
Front Microbiol ; 15: 1389907, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38721597

RESUMEN

Symbiotic microbes are essential for developing and growing Gastrodia elata, an achlorophyllous orchid of high medicinal value. Recently, the cultivation of G. elata in greenhouses has been adopted in Korea to produce mature tubers in a short time. However, no studies have been conducted on the microbial community structure of G. elata cultivated in greenhouse environments. Therefore, we analyzed the temporal features of bacterial and fungal communities in the rhizosphere of G. elata at the juvenile [JT; 2 months after sowing (MAS)], young (YT; 6 MAS), and mature (MT; 11 MAS) tuber stages using culture-dependent and high-throughput sequencing technology. The richness and diversity of the bacterial and fungal communities decreased with tuber growth of G. elata. The symbiotic fungi Mycena sp. and Armillaria sp. as well as tuber extract inhibited the growth of various soil-inhabiting fungal and bacterial strains, indicating that G. elata and its symbiotic fungi play important roles in the selection of rhizosphere microbes. Mortierella rishikesha was the most abundant fungal species in the rhizosphere. We also identified the microorganisms potentially beneficial for G. elata development during greenhouse cultivation. Tubers and symbiotic fungi actively exert selective pressure on rhizosphere microbes, influencing the diversity and abundance of bacterial and fungal communities as G. elata grows. This study is a first report on the temporal microbial community structure of G. elata cultivated in greenhouse. The results on the associated microbiome of G. elata will help understand their beneficial interactions with G. elata and contribute to improvement in cultivation.

3.
Clin Orthop Surg ; 16(2): 335-341, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38562636

RESUMEN

Background: Jones fractures are common injuries that can be treated conservatively or surgically. However, the optimal treatment approach remains controversial. This study aimed to compare the clinical outcomes of conservative and operative treatments for Jones fractures and determine whether surgical treatment is necessary. Methods: A retrospective study was conducted on 69 patients with Jones fractures treated at our hospital. The patients were divided into 2 groups: conservative (C group; n = 46) and operative (O group; n = 23) treatments. Patients were followed up after 2, 6, and 12 weeks, and every 3 months thereafter. However, outpatient follow-ups were conducted between 8 and 10 weeks as needed. The mean follow-up period was 14.5 weeks (range, 12-24 weeks). In group C, the patients were treated with a non-weight-bearing cast for 4-6 weeks, followed by additional weight-bearing boot immobilization before returning to exercise. In group O, patients were treated surgically using a bicortical screw or intramedullary internal fixation. Time to radiologic union, clinical union, return to sports, visual analog scale (VAS), Foot Function Index-Revised Short Form (FFI-RS), and American Orthopedic Foot and Ankle Society (AOFAS) scores were evaluated. Results: Sixty-nine patients were included in the analysis. There were statistically significant differences in the time to radiologic union and return to sports, VAS score in the second week, and FFI-RS score in the 12th week. In group C, favorable outcomes were observed in terms of the time to return to sports, VAS score in the second week, and FFI-RS score in the 12th week. Contrastingly, in group O, better results were observed in time to radiologic union. The AOFAS score was excellent at the final follow-up, with no significant differences between groups. Complication rates were 10.8% and 13% in groups C and O, respectively. Conclusions: Surgical treatment is sometimes necessary for Jones fractures, but conservative treatment should also be considered because of the favorable outcomes. Conservative treatment can be a good option for patients who are risk-averse and place a high value on fracture healing without surgery.


Asunto(s)
Fracturas Óseas , Huesos Metatarsianos , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Huesos Metatarsianos/cirugía , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/cirugía , Fijación Interna de Fracturas/métodos
4.
Phys Rev Lett ; 132(1): 016301, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38242663

RESUMEN

We report the first observation of the spin Hall conductivity spectrum in GaAs at room temperature. Our terahertz polarimetry with a precision of several µrads resolves the Faraday rotation of terahertz pulses arising from the inverse spin Hall effect of optically injected spin-polarized electrons. The obtained spin Hall conductivity spectrum exhibits an excellent quantitative agreement with theory, demonstrating a crossover in the dominant origin from impurity scattering in the dc regime to the intrinsic Berry-curvature mechanism in the terahertz regime. Our spectroscopic technique opens a new pathway to analyze anomalous transports related to spin, valley, or orbital degrees of freedom.

5.
Opt Lett ; 48(23): 6344-6347, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38039263

RESUMEN

We generated gain-switched pulses via electrical pulse excitations in a 1270 nm distributed feedback (DFB) laser diode (LD) with a direct-modulation bandwidth of 30 GHz. The measurements revealed short-pulse widths of 5.3 and 8.8 ps with and without chirp compensation, via a single-mode optical fiber. The 5.3 ps pulses exhibited a spectral width of 0.40 nm (spectral bandwidth of 71 GHz), yielding a time-bandwidth product of 0.38. Although the gain-switched pulses in DFB LDs inherently contain linear and nonlinear chirp, optimized pumping conditions enable generation of nearly transform-limited ps pulses after linear chirp compensation.

6.
J Mol Model ; 30(1): 10, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38093140

RESUMEN

CONTEXT: Area-selective atomic layer deposition (AS-ALD) is a thin film deposition technique developed using conventional ALD by considering the surface chemical nature of the substrate. Selecting appropriate precursors is a critical step in developing an efficient AS-ALD process with high deposition selectivity. However, the current efficiency of research on viable AS-ALD precursors is limited because of the absence of theoretical design rules for precursor chemical structures. In this study, our objective is to propose molecular design principle for precursors for AS-ALD, particularly focusing on achieving high deposition selectivity of oxides on diverse substrates. Current preliminary results suggest that ML-based prediction model may provide a fundamental molecular-level understanding of the reactivity of metal oxide precursors, that can be useful for efficient selection of suitable precursors for AS-ALD. METHODS: We employ density functional theory (DFT) calculations and machine learning (ML) techniques to analyze the relationship between the structure and the surface reactivity of the precursor. Considering DFT calculation data (M06L/def2-tzvp, Gaussian 09 and Orca 4.0) and information on precursor structures, artificial neural networks (ANN, neuralnet, R) are applied to identify critical descriptors of the AS-ALD process. Furthermore, we utilize this ANN model to predict precursor reactivity according to surface terminations.

7.
J Adv Vet Anim Res ; 10(2): 144-150, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37534070

RESUMEN

Objective: The study aimed to investigate the hepatoprotective effects of Gastrodia elata rhizome (GR) on thioacetamide (TAA)-induced liver injury in dogs. We evaluated serum biochemical and hematological parameters, with emphasis on alanine transaminase (ALT), alanine phosphates (ALP), and nitric oxide (NO) levels, in dogs with TAA-induced liver injury. Materials and Methods: The animals were divided into a control group (Con), TAA group, Silymarin group (Sil, 50 mg/kg), Gastrodia rhizome low dose (GRL) (low) + TAA, GRH (high) + TAA, and GR high-dose group (GRH) control group. GRL and GRH were given daily at 50 and 100 mg/kg, respectively. TAA was given on days 1, 4, and 7 at a dose of 300 mg/kg. Results: GR significantly reduced liver injury in treated animals, as indicated by lowered levels of ALT (about 32% at day 21 in both GRL + TAA and GRH + TAA groups), ALP (about 17% and 21% at day 21 in both GRL + TAA, GRH + TAA groups, respectively), and NO (about 36% at day 21 in both GRL + TAA, GRH + TAA groups) compared to the TAA control group. Hematological parameters showed mild changes during the experiment. High-performance liquid chromatography analysis revealed gastrodin, a major component of the GR extract, constitutes 2.6% of the extract. Conclusion: The GR demonstrated significant hepatoprotective effects against TAA-induced liver injury in dogs. The study provides evidence for the potential therapeutic use of GR in the management of liver diseases.

8.
Tissue Eng Regen Med ; 20(1): 83-92, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36562983

RESUMEN

BACKGROUND: The extracellular matrix (ECM) has many functions, such as segregating tissues, providing support, and regulating intercellular communication. Cartilage-derived ECM (CECM) can be prepared via consecutive processes of chemical decellularization and enzyme treatment. The purpose of this study was to improve and treat osteoarthritis (OA) using porcine knee articular CECM. METHODS: We assessed the rheological characteristics and pH of CECM solutions. Furthermore, we determined the effects of CECM on cell proliferation and cytotoxicity in the chondrocytes of New Zealand rabbits. The inhibitory effect of CECM on tumor necrosis factor (TNF)-α-induced cellular apoptosis was assessed using New Zealand rabbit chondrocytes and human synoviocytes. Finally, we examined the in vivo effects of CECM on inflammation control and cartilage degradation in an experimental OA-induced rat model. The rat model of OA was established by injecting monosodium iodoacetate into the intra-articular knee joint. The rats were then injected with CECM solution. Inflammation control and cartilage degradation were assessed by measuring the serum levels of proinflammatory cytokines and C-telopeptide of type II collagen and performing a histomorphological analysis. RESULTS: CECM was found to be biocompatible and non-immunogenic, and could improve cell proliferation without inducing a toxic reaction. CECM significantly reduced cellular apoptosis due to TNF-α, significantly improved the survival of cells in inflammatory environments, and exerted anti-inflammatory effects. CONCLUSION: Our findings suggest that CECM is an appropriate injectable material that mediates OA-induced inflammation.


Asunto(s)
Cartílago Articular , Osteoartritis , Ratas , Humanos , Animales , Conejos , Porcinos , Cartílago Articular/patología , Osteoartritis/tratamiento farmacológico , Condrocitos/metabolismo , Inflamación/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Matriz Extracelular/metabolismo
9.
Tissue Eng Regen Med ; 19(5): 969-986, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35857259

RESUMEN

Various tissues, including the heart, cornea, bone, esophagus, bladder and liver, have been vascularized using the cell sheet technique. It overcomes the limitations of existing techniques by allowing small layers of the cell sheet to generate capillaries on their own, and it can also be used to vascularize tissue-engineered transplants. Cell sheets eliminate the need for traditional tissue engineering procedures such as isolated cell injections and scaffold-based technologies, which have limited applicability. While cell sheet engineering can eliminate many of the drawbacks, there are still a few challenges that need to be addressed. The number of cell sheets that can be layered without triggering core ischemia or hypoxia is limited. Even when scaffold-based technologies are disregarded, strategies to tackle this problem remain a substantial impediment to the efficient regeneration of thick, living three-dimensional cell sheets. In this review, we summarize the cell sheet technology in myocardial infarcted tissue regeneration.


Asunto(s)
Infarto del Miocardio , Ingeniería de Tejidos , Humanos , Infarto del Miocardio/terapia , Trasplante de Células Madre , Tecnología , Ingeniería de Tejidos/métodos
10.
Adv Mater ; 34(32): e2202866, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35700272

RESUMEN

The desire to enhance the efficiency of organic light-emitting devices (OLEDs) has driven to the investigation of advanced materials with fascinating properties. In this work, the efficiency of top-emission OLEDs (TEOLEDs) is enhanced by introducing ampicillin microstructures (Amp-MSs) with dual phases (α-/ß-phase) that induce photoluminescence (PL) and electroluminescence (EL). Moreover, Amp-MSs can adjust the charge balance by Fermi level (EF ) alignment, thereby decreasing the leakage current. The decrease in the wave-guided modes can enhance the light outcoupling through optical scattering. The resulting TEOLED demonstrates a record-high external quantum efficiency (EQE) (maximum: 68.7% and average: 63.4% at spectroradiometer; maximum: 44.8% and average: 42.6% at integrating sphere) with a wider color gamut (118%) owing to the redshift of the spectrum by J-aggregation. Deconvolution of the EL intensities is performed to clarify the contribution of Amp-MSs to the device EQE enhancement (optical scattering by Amp-MSs: 17.0%, PL by radiative energy transfer: 9.1%, and EL by J-aggregated excitons: 4.6%). The proposed TEOLED outperforms the existing frameworks in terms of device efficiency.

12.
Sci Rep ; 12(1): 2300, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-35145146

RESUMEN

Herein, an unprecedented report is presented on the incorporation of size-dependent gold nanoparticles (AuNPs) with polyvinylpyrrolidone (PVP) capping into a conventional hole transport layer, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). The hole transport layer blocks ion-diffusion/migration in methylammonium-lead-bromide (MAPbBr3)-based perovskite light-emitting diodes (PeLEDs) as a modified interlayer. The PVP-capped 90 nm AuNP device exhibited a seven-fold increase in efficiency (1.5%) as compared to the device without AuNPs (0.22%), where the device lifetime was also improved by 17-fold. This advancement is ascribed to the far-field scattering of AuNPs, modified work function and carrier trapping/detrapping. The improvement in device lifetime is attributed to PVP-capping of AuNPs which prevents indium diffusion into the perovskite layer and surface ion migration into PEDOT:PSS through the formation of induced electric dipole. The results also indicate that using large AuNPs (> 90 nm) reduces exciton recombination because of the trapping of excess charge carriers due to the large surface area.

13.
Nanomaterials (Basel) ; 12(4)2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35215047

RESUMEN

Charge transport layers have been found to be crucial for high-performance perovskite solar cells (PSCs). SnO2 has been extensively investigated as an alternative material for the traditional TiO2 electron transport layer (ETL). The challenges facing the successful application of SnO2 ETLs are degradation during the high-temperature process and voltage loss due to the lower conduction band. To achieve highly efficient PSCs using a SnO2 ETL, low-temperature-processed mesoporous TiO2 (LT m-TiO2) was combined with compact SnO2 to construct a bilayer ETL. The use of LT m-TiO2 can prevent the degradation of SnO2 as well as enlarge the interfacial contacts between the light-absorbing layer and the ETL. SnO2/TiO2 bilayer-based PSCs showed much higher power conversion efficiency than single SnO2 ETL-based PSCs.

14.
IEEE Trans Image Process ; 31: 1657-1670, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35085080

RESUMEN

A lightweight blind image denoiser, called blind compact denoising network (BCDNet), is proposed in this paper to achieve excellent trade-offs between performance and network complexity. With only 330K parameters, the proposed BCDNet is composed of the compact denoising network (CDNet) and the guidance network (GNet). From a noisy image, GNet extracts a guidance feature, which encodes the severity of the noise. Then, using the guidance feature, CDNet filters the image adaptively according to the severity to remove the noise effectively. Moreover, by reducing the number of parameters without compromising the performance, CDNet achieves denoising not only effectively but also efficiently. Experimental results show that the proposed BCDNet yields state-of-the-art or competitive denoising performances on various datasets while requiring significantly fewer parameters.

15.
J Stomatol Oral Maxillofac Surg ; 123(3): e85-e89, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34507005

RESUMEN

OBJECTIVE: To compare the postoperative position of the maxilla with the surgical treatment objectives (STO) in bimaxillary orthognathic surgery for evaluating the surgical accuracy and investigating the pattern and cause of the discrepancy. METHODS: Patients undergoing conventional bimaxillary orthognathic surgery by a single oral and maxillofacial surgeon were enrolled. Utilizing the superimposition of preoperative and postoperative computed tomography images, the actual amounts of positional change of both the maxillary central incisor and first molars were compared with those of STO. All the patients were divided into two groups according to the actual discrepancy between STO and the postoperative position and factors that may affect surgical accuracy were analyzed. RESULTS: In 62 cases, the absolute mean value of the positional difference between STO and the actual outcome was 2.20 mm (X-axis, 0.93 mm; Y-axis, 1.31 mm; and Z-axis, 1.09 mm) in the maxillary central incisor. The signed mean value of the central incisor was -0.07 mm, 0.79 mm, and -0.57 mm in the X-, Y-, and Z-axes, respectively, and the value in the Y- and Z-axes showed a statistically significant difference in comparison with STO (P<0.01). Age, sex, skeletal Angle classification, maxillary and mandibular profile, use of 3D virtual surgery, facial asymmetry, and yawing correction did not show a statistically significant correlation with surgical accuracy at the central incisor. CONCLUSION: There was an acceptable range of discrepancy between postoperative maxillary position and STO after orthognathic surgery; however, there was a tendency for posterior and downward movement in the maxillary anterior teeth.


Asunto(s)
Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Asimetría Facial , Humanos , Mandíbula/cirugía , Maxilar/cirugía , Procedimientos Quirúrgicos Ortognáticos/métodos
17.
Mar Drugs ; 19(11)2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34822463

RESUMEN

Representative marine materials such as biopolymers and bioceramics contain bioactive properties and are applied in regenerative medicine and tissue engineering. The marine organism-derived extracellular matrix (ECM), which consists of structural and functional molecules, has been studied as a biomaterial. It has been used to reconstruct tissues and improve biological functions. However, research on marine-derived extracellular vesicles (EVs) among marine functional materials is limited. Recent studies on marine-derived EVs were limited to eco-system studies using bacteria-released EVs. We aimed to expand the range of representative marine organisms such as fish, crustaceans, and echinoderms; establish the extraction process; and study the bioactivity capability of marine EVs. Results confirmed that marine organism ECM-anchored EVs (mEVs) have a similar morphology and cargos to those of EVs in land animals. To investigate physiological effects, lipopolysaccharide (LPS)-infected macrophages were treated with EVs derived from sea cucumber, fish, and shrimp. A comparison of the expression levels of inflammatory cytokine genes revealed that all types of mEVs alleviated pro-inflammatory cytokines, although to different degrees. Among them, the sea cucumber-derived EVs showed the strongest suppression ability. This study showed that research on EVs derived from various types of marine animals can lead to the development of high value-added therapeutics from discarded marine wastes.


Asunto(s)
Antiinflamatorios/farmacología , Organismos Acuáticos , Vesículas Extracelulares/química , Animales , Antiinflamatorios/química , Artemia , Citocinas/efectos de los fármacos , Equinodermos , Peces , Humanos , Macrófagos/efectos de los fármacos , Pepinos de Mar
18.
Nat Commun ; 12(1): 2864, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-34001906

RESUMEN

Stretchable organic light-emitting diodes are ubiquitous in the rapidly developing wearable display technology. However, low efficiency and poor mechanical stability inhibit their commercial applications owing to the restrictions generated by strain. Here, we demonstrate the exceptional performance of a transparent (molybdenum-trioxide/gold/molybdenum-trioxide) electrode for buckled, twistable, and geometrically stretchable organic light-emitting diodes under 2-dimensional random area strain with invariant color coordinates. The devices are fabricated on a thin optical-adhesive/elastomer with a small mechanical bending strain and water-proofed by optical-adhesive encapsulation in a sandwiched structure. The heat dissipation mechanism of the thin optical-adhesive substrate, thin elastomer-based devices or silicon dioxide nanoparticles reduces triplet-triplet annihilation, providing consistent performance at high exciton density, compared with thick elastomer and a glass substrate. The performance is enhanced by the nanoparticles in the optical-adhesive for light out-coupling and improved heat dissipation. A high current efficiency of ~82.4 cd/A and an external quantum efficiency of ~22.3% are achieved with minimum efficiency roll-off.

19.
IEEE Trans Image Process ; 30: 4114-4128, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33798082

RESUMEN

A novel light field super-resolution algorithm to improve the spatial and angular resolutions of light field images is proposed in this work. We develop spatial and angular super-resolution (SR) networks, which can faithfully interpolate images in the spatial and angular domains regardless of the angular coordinates. For each input image, we feed adjacent images into the SR networks to extract multi-view features using a trainable disparity estimator. We concatenate the multi-view features and remix them through the proposed adaptive feature remixing (AFR) module, which performs channel-wise pooling. Finally, the remixed feature is used to augment the spatial or angular resolution. Experimental results demonstrate that the proposed algorithm outperforms the state-of-the-art algorithms on various light field datasets. The source codes and pre-trained models are available at https://github.com/keunsoo-ko/ LFSR-AFR.

20.
Opt Lett ; 46(6): 1277-1280, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33720166

RESUMEN

We have directly generated optical pulses having a duration of 0.56 ps with a peak power of 25 W by gain switching of multi-section semiconductor lasers in which the optimized lengths of the absorption and gain regions were 50 and 200 µm, respectively. Even though the experiment was conducted via impulsive optical pumping at a low temperature, we observed that the multi-section gain switching suppresses the low-energy tail and chirping inherent to conventional gain switching in single-section lasers and is useful in direct short-pulse generation.

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