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1.
Small ; : e2401080, 2024 Apr 02.
Article En | MEDLINE | ID: mdl-38566553

Non-fullerene acceptors (NFAs) significantly enhance photovoltaic performance in organic solar cells (OSCs) using halogenated solvents and additives. However, these solvents are environmentally detrimental and unsuitable for industrial-scale production, and the issue of OSCs' poor long-term stability persists. This report introduces eight asymmetric NFAs (IPCnF-BBO-IC2F, IPCnF-BBO-IC2Cl, IPCnCl-BBO-IC2F, and IPCnCl-BBO-IC2Cl, where n = 1 and 2). These NFAs comprise a 12,13-bis(2-butyloctyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]thiadiazolo[3,4-e]thieno[2'',3'':4',5']thieno[2',3':4,5]pyrrolo[3,2-g]thieno[2',3':4,5]thieno-[3,2-b]indole (BBO) core. One end of the core attaches to a mono- or di-halogenated 9H-indeno[1,2-b]pyrazine-2,3-dicarbonitrile (IPC) end group (IPC1F, IPC1Cl, IPC2F, or IPC2Cl), while the other end connects to a 2-(5,6-dihalo-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (IC) end group (IC2F or IC2Cl). The optical and electronic properties of these NFAs can be finely tuned by controlling the number of halogen atoms. Crucially, these NFAs demonstrate excellent compatibility with PM6 even in o-xylene, facilitating the production of additive-free OSCs. The di-halogenated IPC-based NFAs outperform their mono-halogenated counterparts in photovoltaic performance within OSCs. Remarkably, the di-halogenated IPC-based NFAs maintain 94‒98% of their initial PCEs over 2000 h in air without encapsulation, indicating superior long-term device stability. These findings imply that the integration of di-halogenated IPCs in asymmetric NFA design offers a promising route to efficient, stable OSCs manufactured through environmentally friendly processes.

2.
Life (Basel) ; 14(3)2024 Mar 07.
Article En | MEDLINE | ID: mdl-38541680

This study aimed to implement a deep learning-based super-resolution (SR) technique that can assist in the diagnosis and surgery of trigeminal neuralgia (TN) using magnetic resonance imaging (MRI). Experimental methods applied SR to MRI data examined using five techniques, including T2-weighted imaging (T2WI), T1-weighted imaging (T1WI), contrast-enhancement T1WI (CE-T1WI), T2WI turbo spin-echo series volume isotropic turbo spin-echo acquisition (VISTA), and proton density (PD), in patients diagnosed with TN. The image quality was evaluated using the peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM). High-quality reconstructed MRI images were assessed using the Leksell coordinate system in gamma knife radiosurgery (GKRS). The results showed that the PSNR and SSIM values achieved by SR were higher than those obtained by image postprocessing techniques, and the coordinates of the images reconstructed in the gamma plan showed no differences from those of the original images. Consequently, SR demonstrated remarkable effects in improving the image quality without discrepancies in the coordinate system, confirming its potential as a useful tool for the diagnosis and surgery of TN.

3.
Science ; 383(6678): 70-76, 2024 Jan 05.
Article En | MEDLINE | ID: mdl-38175890

Block copolymer self-assembly affords diverse nanostructures, spanning from spheres and cylinders to networks, offering meticulous control over properties and functionalities at the nanoscale. However, creating thermodynamically stable network structures with high packing frustration remains a challenge. In this study, we report a methodology to access diverse network structures such as gyroid, diamond, and primitive phases from diblock copolymers using end group and linker chemistry. The stability of the medial packing of polymer chain ends (plumber's nightmare structure) over skeletal aggregation (gyroid) is attributed to the interplay between the strength of the end-end interactions and the initial shape of the curvature. Our study establishes an approach to develop tailored network structures from block copolymers, providing an important platform for using block copolymers in nanotechnology applications.

4.
Nanoscale ; 15(45): 18224-18232, 2023 Nov 23.
Article En | MEDLINE | ID: mdl-37942951

Porphyrin dyads (PDMs, where M = Zn and Cu) composed of diphenylporphyrin and tetraphenylporphyrin units, designated as DPDMs and TPDMs, respectively, exhibited remarkable differences in the molecular assemblies depending on the coordination metal ion. Furthermore, TPDMs showed self-sorting behavior during the formation of supramolecular assemblies through the recognition of atomic-level difference.

5.
Bioengineering (Basel) ; 10(11)2023 Oct 26.
Article En | MEDLINE | ID: mdl-38002374

The purpose of this study was to investigate the effects of different peri-implantitis treatment methods (Er,Cr:YSGG laser, diode laser, and electrocautery) on various titanium implant surfaces: machined; sandblasted, large-grit, and acid-etched; and femtosecond laser-treated surfaces. Grade 4 titanium (Ti) disks, with a diameter of 10 mm and a thickness of 1 mm, were fabricated and treated using the aforementioned techniques. Subsequently, each treated group of disks underwent different peri-implantitis treatment methods: Er,Cr:YSGG laser (Biolase, Inc., Foothill Ranch, CA, USA), diode laser (Biolase, Inc., Foothill Ranch, CA, USA), and electrocautery (Ellman, Hicksville, NY, USA). Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and wettability were used to characterize the chemical compositions and surfaces of the treated titanium surfaces. Significant changes in surface roughness were observed in both the electrocautery (Sa value of machined surface = 0.469, SLA surface = 1.569, femtosecond laser surface = 1.741, and p = 0.025) and Er,Cr:YSGG laser (Ra value of machined surface = 1.034, SLA surface = 1.380, femtosecond laser surface = 1.437, and p = 0.025) groups. On femtosecond laser-treated titanium implant surfaces, all three treatment methods significantly reduced the surface contact angle (control = 82.2°, diode laser = 74.3°, Er,Cr:YSGG laser = 73.8°, electrocautery = 76.2°, and p = 0.039). Overall, Er,Cr:YSGG laser and electrocautery treatments significantly altered the surface roughness of titanium implant surfaces. As a result of surface composition after different peri-implantitis treatment methods, relative to the diode laser and electrocautery, the Er,Cr:YSGG laser increased oxygen concentration. The most dramatic change was observed after Er:Cr;YSGG laser treatment, urging caution for clinical applications. Changes in surface composition and wettability were observed but were not statistically significant. Further research is needed to understand the biological implications of these peri-implantitis treatment methods.

6.
J Funct Biomater ; 14(10)2023 Sep 22.
Article En | MEDLINE | ID: mdl-37888151

(1) Background: The purpose of this study was to evaluate how a zirconia implant surface treated with laser technology affects the degree of biofilm formation. (2) Methods: Experimental titanium (Ti) disks were produced that were sandblasted with large grit and acid-etched (T), and they were compared with zirconia (ZrO2) discs with a machined (M) surface topography; a hydrophilic surface topography with a femtosecond laser (HF); and a hydrophobic surface topography with a nanosecond laser (HN) (N = 12 per surface group). An in vitro three-species biofilm sample (Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi)) was applied to each disc type, and bacterial adhesion was assessed after 48 and 72 h of incubation using an anaerobic flow chamber model. Statistical significance was determined using the Kruskal-Wallis H test, with Bonferroni correction used for the post-hoc test (α = 0.05). (3) Results: Compared to the T group, the M group exhibited more than twice as many viable bacterial counts in the three-species biofilm samples (p < 0.05). In comparison to the T group, the HF group had significantly higher viable bacterial counts in certain biofilm samples at 48 h (Aa and Pi) and 72 h (Pi) (p < 0.05). The HN group had higher viable bacterial counts in Pi at 48 h (5400 CFU/mL, p < 0.05) than the T group (4500 CFU/mL), while showing significantly lower viable bacterial counts in Pg at both 48 (3010 CFU/mL) and 72 h (3190 CFU/mL) (p < 0.05). (4) Conclusions: The surface treatment method for zirconia discs greatly influences biofilm formation. Notably, hydrophobic surface treatment using a nanosecond laser was particularly effective at inhibiting Pg growth.

7.
J Funct Biomater ; 14(10)2023 Oct 09.
Article En | MEDLINE | ID: mdl-37888167

This study evaluated the effects of various mechanical debridement methods on the surface roughness (Ra) of dental implants, comparing femtosecond laser-treated surfaces with conventionally machined and sandblasted with large-grit sand and acid-etched (SLA) implant surfaces. The fabrication of grade 4 titanium (Ti) disks (10 mm in diameter and 1 mm thick) and the SLA process were carried out by a dental implant manufacturer (DENTIS; Daegu, Republic of Korea). Subsequently, disk surfaces were treated with various methods: machined, SLA, and femtosecond laser. Disks of each surface-treated group were post-treated with mechanical debridement methods: Ti curettes, ultrasonic scaler, and Ti brushes. Scanning electron microscopy, Ra, and wettability were evaluated. Statistical analysis was performed using the Kruskal-Wallis H test, with post-hoc analyses conducted using the Bonferroni correction (α = 0.05). In the control group, no significant difference in Ra was observed between the machined and SLA groups. However, femtosecond laser-treated surfaces exhibited higher Ra than SLA surfaces (p < 0.05). The application of Ti curette or brushing further accentuated the roughness of the femtosecond laser-treated surfaces, whereas scaling reduced the Ra in SLA surfaces. Femtosecond laser-treated implant surfaces, with their unique roughness and compositional attributes, are promising alternatives in dental implant surface treatments.

8.
Adv Sci (Weinh) ; 10(27): e2304039, 2023 Sep.
Article En | MEDLINE | ID: mdl-37501319

High-performance chiroptical synaptic phototransistors are successfully demonstrated using heterojunctions composed of a self-assembled nanohelix of a π-conjugated molecule and a metal oxide semiconductor. To impart strong chiroptical activity to the device, a diketopyrrolopyrrole-based π-conjugated molecule decorated with chiral glutamic acid is newly synthesized; this molecule is capable of supramolecular self-assembly through noncovalent intermolecular interactions. In particular, nanohelix formed by intertwinded fibers with strong and stable chiroptical activity in a solid-film state are obtained through hydrogen-bonding-driven, gelation-assisted self-assembly. Phototransistors based on interfacial charge transfer at the heterojunction from the chiroptical nanohelix to the metal oxide semiconductor show excellent chiroptical detection with a high photocurrent dissymmetry factor of 1.97 and a high photoresponsivity of 218 A W-1 . The chiroptical phototransistor demonstrates photonic synapse-like, time-dependent photocurrent generation, along with persistent photoconductivity, which is attributed to the interfacial charge trapping. Through the advantage of synaptic functionality, a trained convolutional neural network successfully recognizes noise-reduced circularly polarized images of handwritten alphabetic characters with better than 89.7% accuracy.

9.
J Xray Sci Technol ; 30(6): 1099-1114, 2022.
Article En | MEDLINE | ID: mdl-36120755

OBJECTIVE: To present an optimized examination model by analyzing the risk of disease and image quality according to the combination of the ion chamber of automatic exposure control (AEC) with digital radiography (DR). METHODS: The X-ray quality was analyzed by first calculating the percentage average error (PAE) of DR. After that, when using AEC, the combination of the ion chambers was the same as the left and centre and right, right and centre, left and centre, centre, right, and left, for a total of six. Accordingly, the entrance surface dose (ESD), risk of disease, and image quality were evaluated. ESD was obtained by attaching a semiconductor dosimeter to the L4 level of the lumbar spine, and then irradiating X-rays to dosimeter centre through average and standard deviation of radiation dose. The calculated ESD was input into the PCXMC 2.0 programme to evaluate disease risk caused by radiation. Meanwhile, image quality according to chamber combination was quantified as the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) through Image J. RESULTS: X-ray quality of DR used in the experiment was within the normal range of±10. ESD of six ion chamber combinations was 1.363mGy, 0.964mGy, 0.946mGy, 0.866mGy, 0.748mGy, 0.726mGy for lumbar anteroposterior (AP), and the lumbar lateral values were 1.126mGy, 0.209mGy, 0.830mGy, 0.662mGy, 0.111mGy, and 0.250mGy, respectively. Meanwhile, disease risk analyzed through PCXMC 2.0 was bone marrow, colon, liver, lung, stomach, urinary and other tissue cancer, and disease risk showed a tendency to increase in proportion to ESD. SNR and CNR recorded the lowest values when three chambers were combined and did not show proportionality with dose, while showed the highest values when two chambers were combined. CONCLUSION: In this study, combination of three ion chambers showed the highest disease risk and lowest image quality. Using one ion chamber showed the lowest disease risk, but lower image quality than two ion chambers. Therefore, if considering all above factors, combination of two ion chambers can optimally maintain the disease risk and image quality. Thus, it is considered an optimal X-ray examination parameter.


Radiographic Image Enhancement , Radiographic Image Enhancement/methods , X-Rays , Radiation Dosage , Radiography , Signal-To-Noise Ratio , Phantoms, Imaging
10.
Chem Sci ; 12(42): 14083-14097, 2021 Nov 03.
Article En | MEDLINE | ID: mdl-34760192

The concurrent enhancement of short-circuit current (J SC) and open-circuit voltage (V OC) is a key problem in the preparation of efficient organic solar cells (OSCs). In this paper, we report efficient and stable OSCs based on an asymmetric non-fullerene acceptor (NFA) IPC-BEH-IC2F. The NFA consists of a weak electron-donor core dithienothiophen[3,2-b]-pyrrolobenzothiadiazole (BEH) and two kinds of strong electron-acceptor (A) units [9H-indeno[1,2-b]pyrazine-2,3-dicarbonitrile (IPC) with a tricyclic fused system and 2-(5,6-difluoro-3-oxo-2,3-dihydro-1H-inden-1-ylidene)malononitrile (IC2F)]. For comparison, the symmetric NFAs IPC-BEH-IPC and IC2F-BEH-IC2F were characterised. The kind of flanking A unit significantly affects the light absorption features and electronic structures of the NFAs. The asymmetric IPC-BEH-IC2F has the highest extinction coefficient among the three NFAs owing to its strong dipole moment and highly crystalline feature. Its highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels lie between those of the IPC-BEH-IPC and IC2F-BEH-IC2F molecules. The IPC group also promotes molecular packing through the tricyclic π-conjugated system and achieves increased crystallinity compared to that of the IC2F group. Inverted-type photovoltaic devices based on p-type polymer:NFA blends with PBDB-T and PM6 polymers as p-type polymers were fabricated. Among all these devices, the PBDB-T:IPC-BEH-IC2F blend device displayed the best photovoltaic properties because the IPC unit provides balanced electronic and morphological characteristics. More importantly, the PBDB-T:IPC-BEH-IC2F-based device exhibited the best long-term stability owing to the strongly interacting IPC moiety and the densely packed PBDB-T:IPC-BEH-IC2F film. These results demonstrate that asymmetric structural modifications of NFAs are an effective way for simultaneously improving the photovoltaic performance and stability of OSCs.

11.
Sensors (Basel) ; 21(14)2021 Jul 07.
Article En | MEDLINE | ID: mdl-34300410

The aim of this study was to quantitatively assess the residual adhesive on orthodontic ceramic bracket-removed dental surface. In orthodontic process, ceramic bracket was repeated debonding physically, then the adhesive remained on the dental surface. The residual adhesive caused a lack of adhesive strength between dental and ceramic bracket. Since commonly used adhesive in orthodontics is translucent, residual adhesive is hard to be detected with conventional microscopes. Therefore, 1310 nm center wavelength swept-source OCT system based on laboratory customized image processing algorithm was used for the precise detection of residual adhesive on tooth surface. The algorithm separates residual adhesive from dental surface by comparing the height of adjacent B-scan images, while providing color-scaled images emphasizing the thickness information of residual adhesive. Finally, the acquired results were compared with microscopic and adhesive remnant index scoring gold standards, while the comparison confirmed the potential merits and the improvements of the proposed method over gold standards.


Adhesives , Orthodontic Brackets , Algorithms , Ceramics , Materials Testing , Surface Properties , Tomography, Optical Coherence
12.
Ultrason Sonochem ; 73: 105545, 2021 May.
Article En | MEDLINE | ID: mdl-33836371

Lacquer sap has received much attention as a traditional natural resin because it is a renewable and eco-friendly biopolymer resource unlike artificial coating materials. However, strict drying conditions and long drying times of lacquer sap should be modified to expand its applications. This study presents the first attempt to investigate the effect of different amplitudes of ultrasonic waves on the lacquer sap composed of water-in-oil (W/O) emulsion droplets and the mechanical properties of the resultant film by solvent evaporation. Acoustically induced cavitation via batch ultrasonication facilitates the generation of submicron-sized W/O emulsion. The drying time of sonicated lacquer sap was noticeably shortened as the amplitude of acoustic power increased. Interestingly, the transparency of the film cast from lacquer sap consisting of the smallest emulsion droplets increased significantly, weakening the degree of colour change from caramel-like yellow to dark brown as polymerisation progressed. These are attributed to the effective and frequent contact of laccase enzyme with urushiol at the increased interfacial area of nano-emulsified W/O droplets pulverised by ultrasonic waves. The quinone radical-generation in the interface layer and its transfer to the urushiol oil phase through water-insoluble glycoprotein emulsifier are greatly promoted, resulting in highly cross-linked, dense three-dimensional polymer networks, which also increased the lacquer film hardness after drying. As the emulsion droplet size decreased, the mutual interaction between the catechol moiety of urushiol and the substrates increased, resulting in improved adhesion. The nano-emulsification of the lacquer sap by ultrasonic waves can be used in a simple, effective, and eco-friendly way to shorten the drying time and improve the film characteristics of natural resins. This approach could pave the way for its wide range of applications in industrial fields, taking into account green and sustainable chemistry.

13.
J Med Syst ; 44(10): 183, 2020 Sep 04.
Article En | MEDLINE | ID: mdl-32886270

The purpose of this study is to evaluate detector performance using histogram and entropy analysis according to the sensitivity change of the automatic exposure control (AEC). The experiment was performed as follows: The sensitivity of the detector was analyzed through a normalized histogram with sensitivities of S200, S400, S800, and S1000 of the AEC; the entropy of the image was then analyzed, and the signal volume of the detector was evaluated according to the sensitivity change. As the sensitivity of the AEC was increased from S200 to S1000, the histogram showed underflow, quantization separation, and dynamic range discrepancy. In addition, entropy showed a decrease as sensitivity was set higher; in particular, entropy degradation was more prominent at sensitivities above S800. Through the histogram and entropy analysis, it was concluded that the detector does not reproduce the sensitivity and signal volume accurately when the sensitivity of the AEC is set high in performance evaluation.


Radiographic Image Enhancement , Entropy , Humans , Phantoms, Imaging , Radiation Dosage
14.
Food Sci Biotechnol ; 28(6): 1891-1897, 2019 Dec.
Article En | MEDLINE | ID: mdl-31807363

In this study, the ATP degradation products and microbial growth during storage of flatfish were measured for assessing its freshness. LOD and LOQ of the ATP degradation products including ADP, AMP, IMP, HxR and Hx were 0.01-0.11 and 0.02-0.37 µg/g respectively, and the recovery ranged from 35.8 to 98.8%. The Hx level increased significantly during the storage period, regardless of storage temperature (p < 0.05). The initial Hx level was 245.27 µg/g, and this rapidly increased to 2563.72, 6643.69, and 4236.65 µg/g at 4, 10, and 25 °C at 14 days, 8 days, and 12 h, respectively. The correlation coefficient (R 2) between microbial growth and Hx percentage ranged from 0.7709 to 0.8939. Based on the nitroblue tetrazolium colorimetric assay, the optical density of flatfish stored at 4 °C increased from 2.45 to 13.29 at 82 h of storage, which was equivalent to 442% increment.

15.
J Nanosci Nanotechnol ; 13(11): 7596-9, 2013 Nov.
Article En | MEDLINE | ID: mdl-24245299

SnO2 nanostuctures were formed on indium-tin-oxide (ITO)-coated glass substrates by using an electrochemical deposition (ECD) method. X-ray photoelectron spectroscopy (XPS) spectra showed the existence of elemental Sn and O in the samples, indicative of the formation of SnO2 materials. An XPS spectrum showing the O 1s peak at a binding energy of 531.5 eV indicated that the oxygen atoms were bonded to the SnO2. Field-emission scanning electron microscopy (FE-SEM) images showed that the samples formed by using the ECD method had SnO2 nanostructures with a size between 280 and 350 nm. FE-SEM images showed that the size of the SnO2 nanostructures formed at 65 degrees C for 30 min increased with decreasing applied voltage. X-ray diffraction (XRD) patterns showed that the SnO2 nanostrucures had tetragonal structures with cell parameters of a = 4.738 A and c = 3.187 A. XRD results showed that the peak intensity of the (110) plane increased with decreasing applied voltage, indicative of a preferencial orientation of the (110) plane.


Crystallization/methods , Electroplating/methods , Glass/chemistry , Metal Nanoparticles/chemistry , Tin Compounds/chemistry , Tin Compounds/radiation effects , Adsorption/radiation effects , Electromagnetic Fields , Glass/radiation effects , Materials Testing , Metal Nanoparticles/radiation effects , Metal Nanoparticles/ultrastructure , Particle Size , Radiation Dosage
16.
Int J Pharm ; 421(2): 397-404, 2011 Dec 15.
Article En | MEDLINE | ID: mdl-22016032

Superparamagnetic iron oxide nanoparticles (SPIONs) have been exploited as an elegant vehicle to enhance gene delivery efficiencies in gene therapy applications. We developed a magnetically guided adeno-associated virus (AAV) delivery system for enhancing gene delivery to HEK293T and PC12 cell lines. Wild-type AAV2 and a novel AAV vector, AAVr3.45, which was directly evolved in a previous study to possess diverse cell tropisms, were used as gene carriers. Additionally, the affinity of each viral vector to heparin was employed as a moiety to immobilize virus onto heparin-coated SPIONs (HpNPs). Magnetically guided AAV delivery resulted fast and efficient cellular transduction. Importantly, a short exposure of virus to target cells under a magnetic field (<180min) yielded comparable transduction produced by the conventional gene-delivery protocol (i.e., 24h-incubation of virus with target cells prior to replacing with fresh medium). Additionally, magnetic guidance of AAV encoding nerve growth factor (NGF) produced sufficient functional NGF, leading to robust neurite elongation by PC12 as compared to direct NGF protein delivery or non-magnetic delivery. The successful establishment of a magnetically guided AAV delivery system, with the ability to efficiently and rapidly infect target cells, will provide a powerful platform for a variety of gene therapy applications.


Dependovirus , Gene Transfer Techniques , Genetic Vectors , Heparin , Magnetite Nanoparticles , Animals , Cell Survival , Genetic Therapy/methods , HEK293 Cells , Heparin/pharmacology , Humans , Nerve Growth Factor/genetics , Nerve Growth Factor/metabolism , Neurites/drug effects , Neurites/physiology , PC12 Cells , Rats , Transduction, Genetic
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