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1.
Sensors (Basel) ; 22(15)2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35957441

RESUMO

Given the huge demand for wire in today's society, the quality of the wire is especially required. To control the quality of the produced wire, the industry has a great desire for automated optical inspection technology. This technology is a high-speed and highly accurate optical image inspection system that uses mechanical sensing equipment to replace the human eye as the inspection method and simulates manual operation by means of a robotic arm. In this paper, a high-performance algorithm for the automated optical inspection of wire color sequence is proposed. This paper focuses on the design of a high-speed wire color sequence detection that can automatically adapt to different kinds of wires and recognition situations, such as a single wire with only one color, and one or two wires covered with aluminum foil. To be further able to successfully inspect even if the wire is short in the screen and the two wires are close to each other, we calculate the horizontal gradient of the wires by edge detection and morphological calculation and identify the types and color sequences of the wires in the screen by a series of discriminative mechanisms. Experimental results show that this method can achieve good accuracy while maintaining a good computation speed.


Assuntos
Algoritmos , Dispositivos Ópticos , Humanos
2.
ACS Appl Mater Interfaces ; 14(2): 3467-3475, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34995438

RESUMO

A two-dimensional (2D) nonvolatile memory device architecture to improve the long-term charge retention with the minimum charge loss without compromising storage capacity and the extinction ratio for practical applications has been an imminent demand. To address the current issue, we adopted a novel type-II band-aligned heterobilayer channel comprising vertically stacked monolayer WSe2 nanodots on monolayer WS2. The band offset modulation leads to electron doping from WSe2 nanodots into the WS2 channel without any external driving electric field. As a result, the tested device outperformed with a memory window as high as 34 V and a negligible charge loss of 7% in a retention period of 10 years while maintaining a high extinction ratio of 106. The doping technique presented in this work provides a feasible route to modulate the electrical properties of 2D channel materials without hampering charge transport, paving the way for high-performance 2D memory devices.

3.
Sensors (Basel) ; 21(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34695936

RESUMO

With advancements in technology, more and more research is being focused on enhancing daily life quality and convenience. Along with the increase in the development of gesture control systems, many controllers, such as the keyboard, mouse, and other devices, have been replaced with remote control products, which are gradually becoming more intuitive for users. However, vision-based hand gesture recognition systems still have many problems to overcome. Most hand detection methods adopt a skin filter or motion filter for pre-processing. However, in a noisy environment, it is not easy to correctly extract interesting objects. In this paper, a VLSI design with dual-cameras has been proposed to construct a depth map with a stereo matching algorithm and recognize hand gestures. The proposed system adopts an adaptive depth filter to separate interesting foreground objects from the background. We also propose dynamic gesture recognition using depth and coordinate information. The system can perform static and dynamic gesture recognition. The ASIC design is implemented in TSMC 90 nm with about 47.3 K gate counts, and 27.8 mW of power consumption. The average accuracy of each gesture recognition is 83.98%.


Assuntos
Gestos , Reconhecimento Automatizado de Padrão , Algoritmos , Mãos , Movimento (Física) , Reconhecimento Psicológico
4.
Appl Opt ; 60(20): 5837-5845, 2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34263803

RESUMO

Pearl identification plays a key role to maintain transparency in the gem industry by disclosing potential color treatments and classifying pearl species. Current techniques for pearl identification have been limited by expensive instrumentations and long measurement time, severely restricting their use outside of major gemological laboratories. There is a strong demand for simple and inexpensive identification instruments designed for non-specialized users and small-scale gemological laboratories. For this purpose, we demonstrate a portable fluorescence spectroscopy for pearl treatment detection and species classification based on pearl's nacre fluorescence detection. This device can be used to rapidly separate naturally colored pearls from treated colored pearls, detect potential treatments applied to white colored pearls, and separate pearls between certain species in seconds, based on their differences in nacre fluorescence intensity. The system enables noninvasive testing of loose pearls, pearl strands, and mounted pearl jewelry under normal office lighting conditions. The experimental prototype demonstrates high accuracy for automatic pearl color treatment screening, referring 100% of the treated colored pearls. Furthermore, similar protocols can be applied to evaluate popular pearl enhancements such as bleaching and to extend its application to separate akoya pearls and their South Sea counterparts.

5.
Mater Sci Eng C Mater Biol Appl ; 125: 112093, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33965103

RESUMO

In 2017 the World Health Organization listed carbapenem-resistant K. pneumoniae as a critical priority for developing a novel antimicrobial agent. Here we report on our investigation of the antibacterial efficacy of silver nanoparticles (AgNPs), confined to a mesostructured material and designated as an Ag/80S bioactive nanocomposite, against carbapenem-resistant K. pneumoniae. Results from a textural analysis indicate a 7.5 nm mesopore size and 307.6 m2/g surface area for Ag/80S. UV-Vis spectrum and transmission electron microscope images of Ag/80S revealed a uniform AgNP size distribution with an approximately 3.5 nm average. ICP-MS analysis demonstrated a significantly higher silver content in TSB (a protein-rich environment) compared to ultrapure water, suggesting a controllable release of Ag/80S and thus designated as the inspired Ag/80S. Minimum inhibitory concentration (MIC) values against 16 K. pneumoniae isolates ranged from 0.25 to 0.5% (2.5 to 5.0 mg/ml). NIH 3T3 fibroblast viability at 0.25% exceeded 80% and at 0.5% just under 70%, suggesting low cytotoxicity. Mechanistic study results indicate that the inspired Ag/80S attached to and deformed bacterial cells and induced a time-dependent accumulation of reactive oxygen species, leading to bacterial death. Further, inspired Ag/80S significantly extended median survival time in a Caenorhabditis elegans animal model infected with carbapenem-resistant K. pneumoniae ATCC BAA-1705. Combined, we found a novel Ag/80S which could prevent aggregation of AgNP and control its release via a specific environment for medical use against carbapenem-resistant K. pneumoniae.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Animais , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Prata/farmacologia
6.
Appl Opt ; 60(12): 3412-3421, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33983246

RESUMO

We demonstrate a gemstone screening device based on fluorescence spectroscopy. The device can be used to rapidly separate colorless and near-colorless (D to J color grades) natural diamonds from laboratory grown diamonds and diamond simulants, detect multi-treated pink diamonds, and identify certain colored gemstones, such as corundum, spinel, beryl, and zoisite. The device's reflection fiber probe enables testing of both loose and mounted gemstones with exposed facet faces that are larger than 0.9 mm. The experimental prototype demonstrates high accuracy for automatic diamond gemstone screening, referring 100% of the laboratory grown diamonds and simulants tested. The pink diamond screening algorithm can detect 100% of pink multi-treated diamonds and laboratory grown diamonds. Finally, the suitability of this device for the fluorescence analysis of corundum, beryl, spinel, zoisite, garnet, and topaz was evaluated.

7.
Psychol Med ; 51(4): 579-586, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-31769374

RESUMO

BACKGROUND: Although the literature documents low executive functions and sleep deficits in individuals with autism spectrum disorder or subclinical autistic traits, no study has simultaneously examined their relationships in the general child population. This study aimed to examine whether autistic traits impacted real-world executive functions through insufficient sleep in a nationally representative sample of children. METHODS: This was a national survey of 6832 primary and secondary school students, aged 8-14 years old, with equal sex distribution (3479 boys, 50.8%). Parents reported their child's nocturnal sleep duration and the need for sleep to maintain their daytime function and the Social Responsiveness Scale and the Behavior Rating Inventory of Executive Function (BRIEF) for their children's autistic traits and real-world executive functions, respectively. RESULTS: We found that autistic traits exerted indirect effects on real-world executive functions through sleep deficits, independent of sex, and age. Moreover, such an indirect effect was observed only from restricted and repetitive behaviors to executive functions through sleep deficits, but not in the other components of autistic traits (i.e. social communication and interaction). CONCLUSIONS: Our novel findings underscore the importance of sleep and autistic traits in executive functions and suggest potential mechanisms that may underlie the observed correlational structure among autistic behaviors, sleep deficits, and low executive function performance.


Assuntos
Transtorno Autístico/epidemiologia , Função Executiva , Análise de Mediação , Privação do Sono/epidemiologia , Adolescente , Criança , Comunicação , Família , Feminino , Humanos , Masculino , Pais , Fatores Sexuais , Sono , Inquéritos e Questionários , Taiwan/epidemiologia
8.
ACS Appl Mater Interfaces ; 12(35): 39496-39504, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32805877

RESUMO

In this study, we designed a surface phase-matched transmission enhancement top electrode-Ag/indium tin oxide (ITO) structure for highly efficient and aesthetic semitransparent organic photovoltaics (ST-OPVs). The purposed highly transparent back electrodes (Ag/ITO) could selectively decrease visible reflection and increase transparency accordingly. By altering the thicknesses of the Ag and ITO layers, we could control the transmittance curve and increase the transparency of the ST-OPV devices. Devices based on PTB7-Th:IEICO-4F and PM6:Y6:PC71BM displayed outstanding performance (8.1 and 10.2%, respectively) with high photopic-weighted visible light transmittance (36.2 and 28.6%, respectively). The outstanding visible and near-infrared light harvesting of PM6:Y6:PC71BM further allowed a new application: double-sided energy harvesting from solar and indoor illumination. The simple optical design of a top electrode displaying high transparency/conductivity has a wide range of potential applications in, for example, greenhouse photovoltaics, tandem cells, and portable devices.

9.
ACS Nano ; 14(4): 4559-4566, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32271535

RESUMO

Performance of 2D photodetectors is often predominated by charge traps that offer an effective photogating effect. The device features an ultrahigh gain and responsivity, but at the cost of a retarded temporal response due to the nature of long-lived trap states. In this work, we devise a gain mechanism that originates from massive charge puddles formed in the type-II 2D lateral heterostructures. This concept is demonstrated using graphene-contacted WS2 photodetectors embedded with WSe2 nanodots. Upon light illumination, photoexcited carriers are separated by the built-in field at the WSe2/WS2 heterojunctions (HJs), with holes trapped in the WSe2 nanodots. The resulting WSe2 hole puddles provide a photoconductive gain, as electrons are recirculating during the lifetime of holes that remain trapped in the puddles. The WSe2/WS2 HJ photodetectors exhibit a responsivity of 3 × 102 A/W with a gain of 7 × 102 electrons per photon. Meanwhile, the zero-gate response time is reduced by 5 orders of magnitude as compared to the prior reports for the graphene-contacted pristine WS2 monolayer and WS2/MoS2 heterobilayer photodetectors due to the ultrafast intralayer excitonic dynamics in the WSe2/WS2 HJs.

10.
J Chin Med Assoc ; 83(1): 77-83, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31714443

RESUMO

BACKGROUND: Venomous snakebites are common during hot seasons in Taiwan. However, rarely is venom spat directly into the subject's eyes, causing eye injury. Despite being uncommon, analytical data regarding venom-spit ophthalmia in Taiwan have been lacking. This study thus aimed to conduct an epidemiological survey on Naja atra venom-spit ophthalmia in Taiwan during the past decades to improve future care of such patients. METHODS: Registered records of cases with snake venom injuries at the Taiwan National Poison Control Center from 1990 to 2016 were retrospectively reviewed, enrolling those with records of cobra venom-spit eye injuries and excluding exotic species. Demographic data, clinical symptoms, snake species, ocular conditions, management, and outcomes were recorded and analyzed. RESULTS: A total of 39 cases suffering from Naja atra venom-spit ophthalmia were enrolled. The overall incidence rate was 1.6 cases per million people from 1990 to 2016. Among the included cases, most were unilaterally injured (82%), male (95%), aged 18 to 59 years (90%), injured during catching (51%), and injured in spring and summer (92%). Ocular symptoms occurred in 90% of the cases, majority of which included ocular pain (90%) and redness (85%). Conjunctivitis (67%) and corneal injury (59%) of involved eyes were common. Immediate water irrigations were done in all cases, most of whom received further topical eye drops, including antibiotics, corticosteroids, and vasoconstrictors. Although topical or intravenous antivenoms were administered in 11 cases, no obviously superior outcome was observed. Most cases (77%) were symptom free after the acute stage. CONCLUSION: Although Naja atra venom-spit ophthalmia in Taiwan is uncommon, the risk for transient ocular symptoms and corneal/conjunctival injury does exists. Prompt ocular irrigation and professional ophthalmic care after envenomation help prevent serious ocular sequelae. Moreover, superior outcomes were not achieved with the use of antivenom. Nonetheless, further studies are required to clarify the role antivenoms play in venom-spit ophthalmia.


Assuntos
Venenos Elapídicos/toxicidade , Endoftalmite/epidemiologia , Adolescente , Adulto , Endoftalmite/etiologia , Endoftalmite/terapia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Mordeduras de Serpentes/epidemiologia , Inquéritos e Questionários , Taiwan/epidemiologia , Fatores de Tempo , Adulto Jovem
11.
Materials (Basel) ; 12(21)2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31653052

RESUMO

In this paper, a strengthening method for the damaged high-temperature steel pipeline using inorganic insulation material which was confined by carbon fiber reinforcement plastic (CFRP) composite materials was proposed. Two inorganic insulation materials were composed of magnesium phosphate cement (MPC) mixing with perlite and vermiculite powders, respectively. The influences of insulation material composites with various ratios of the perlite or vermiculite powder were discussed, in terms of compressive strength and thermal conductivity coefficients of inorganic insulation materials. The insulation materials confined by carbon fiber reinforced polymer jackets for enhancing the mechanical behavior were also investigated. From the experimental results, the main finding of the work was that the inorganic insulation materials added to the perlite powder represented greater insulation capability than added vermiculite ones under the condition of the same compressive strength. Different ratios of perlite inorganic insulation material cylinders with the dimension of ϕ 10 cm × 20 cm were confined by one layer and two layers of CFRP composite material. The compressive strength of the specimens increased by 258%-927% after using 1-layer CFRP composite material and increased by 480%-1541% after applying 2-layer CFRP composite material. A peak strength prediction model of insulation materials confined by CFRP was proposed, and it was found that the proposed model accurately predicted the peak strength of the inorganic insulation material cylinder. Finally, a verification test of the strengthening method for damaged high-temperature pipeline was performed to prove that the proposed strengthening method is feasible.

12.
ACS Appl Mater Interfaces ; 11(39): 35969-35976, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31532619

RESUMO

InSe is a high-mobility layered semiconductor with mobility being highly sensitive to any surrounding media that could act as a source of extrinsic scattering. However, little effort has been made to understand electronic transport in thin InSe layers with native surface oxide formed spontaneously upon exposure to an ambient environment. Here, we explore the influence of InOx/InSe interfacial trap states on electronic transport in thin InSe layers. We show that wet oxidation (processed in an ambient environment) causes massive deep-lying band-tail states, through which electrons conduct via 2D variable-range hopping with a short localization length of 1-3 nm. In contrast, a high-quality InOx/InSe interface can be formed in dry oxidation (processed in pure oxygen), with a low trap density of 1012 eV-1 cm-2. Metal-insulator transition can be thus observed in the gate sweep of the field-effect transistors (FETs), indicative of band transport predominated by extended states above the mobility edge. A room-temperature band mobility of 103 cm2/V s is obtained. The profound difference in the transport behavior between the wet and dry InSe FETs suggests that fluctuating Coulomb potential arising from trapped charges at the InOx/InSe interface is the dominant source of disorders in thin InSe channels.

13.
ACS Omega ; 3(11): 14665-14670, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30555985

RESUMO

Chemical warfare agents such as sarin are highly toxic, and detection of even trace levels is important. Using a hydrogel film containing a built-in two-dimensional chemical potential gradient, we demonstrate the detection of a sarin simulant under conditions potentially as low as a level 1 (6.90 × 10-9 mg/cm3 for 10 min) Acute Exposure Guideline Level sarin exposure. Specifically, the sarin simulant diisopropyl fluorophosphate (DFP) is aerosol-deposited on a hydrogel film containing a built-in ionic chemical gradient and the enzyme, diisopropyl fluorophosphatase (DFPase). DFPase degrades the DFP, releasing fluoride ions. The fluoride ions are then concentrated by the gradient to a miniature electrochemical sensor embedded in the hydrogel providing a 30-fold amplification of the fluoride ion signal, which is an indication of exposure to DFP, relative to a gradient-free system. This method is general for agents which hydrolyze into chemically detectable ionic species.

14.
J Am Chem Soc ; 140(4): 1372-1384, 2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29314839

RESUMO

Anion-exchange membranes (AEMs) consisting of poly(vinyl benzyl trimethylammonium)-b-poly(methylbutylene) of three different ion exchange capacities (IECs), 1.14, 1.64, and 2.03 mequiv g-1, are studied by High-Resolution Thermogravimetry, Modulated Differential Scanning Calorimetry, Dynamic Mechanical Analysis, and Broadband Electrical Spectroscopy in their OH- form. The thermal stability and transitions are elucidated, showing a low temperature Tg and a higher temperature transition assigned to a disorder-order transition, Tδ, which depends on the IEC of the material. The electric response is analyzed in detail, allowing the identification of three polarizations (only two of which contribute significantly to the overall conductivity, σEP and σIP,1) and two dielectric relaxation events (ß1 and ß2), one associated with the tolyl side groups (ß1) and one with the cationic side chains (ß2). The obtained results are integrated in a coherent picture and a conductivity mechanism is proposed, involving two distinct conduction pathways, σEP and σIP,1. Importantly, we observed a reordering of the ion pair dipoles which is responsible for the Tδ at temperatures higher than 20 °C, which results in a dramatic decrease of the ionic conductivity. Clustering is highly implicated in the higher IEC membrane in the hydroxyl form, which reduces the efficiency of the anionic transport.

15.
J Biomed Opt ; 22(12): 1-17, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29260538

RESUMO

Optical coherence tomography (OCT) is an imaging technique optically analogous to ultrasound that can generate depth-resolved images with micrometer-scale resolution. Advances in fiber optics and miniaturized actuation technologies allow OCT imaging of the human body and further expand OCT utilization in applications including but not limited to cardiology and gastroenterology. This review article provides an overview of current OCT development and its clinical utility in the gastrointestinal tract, including disease detection/differentiation and endoscopic therapy guidance, as well as a discussion of its future applications.


Assuntos
Gastroenterologia/instrumentação , Trato Gastrointestinal/diagnóstico por imagem , Tomografia de Coerência Óptica/tendências , Tecnologia de Fibra Óptica , Gastroenterologia/tendências , Humanos
16.
Opt Lett ; 42(16): 3193-3196, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28809905

RESUMO

Endoscopic optical coherence tomography (OCT) instruments are mostly side viewing and rely on at least one proximal scan, thus limiting accuracy of volumetric imaging and en face visualization. Previous forward-viewing OCT devices had limited axial scan speeds. We report a forward-viewing fiber scanning 3D-OCT probe with 900 µm field of view and 5 µm transverse resolution, imaging at 1 MHz axial scan rate in the human gastrointestinal tract. The probe is 3.3 mm diameter and 20 mm rigid length, thus enabling passage through the endoscopic channel. The scanner has 1.8 kHz resonant frequency, and each volumetric acquisition takes 0.17 s with 2 volumes/s display. 3D-OCT and angiography imaging of the colon was performed during surveillance colonoscopy.

17.
J Biomed Opt ; 22(7): 76001, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28687822

RESUMO

Radiofrequency ablation (RFA) is widely used for the eradication of dysplasia and the treatment of early stage esophageal carcinoma in patients with Barrett's esophagus (BE). However, there are several factors, such as variation of BE epithelium (EP) thickness among individual patients and varying RFA catheter-tissue contact, which may compromise RFA efficacy. We used a high-speed optical coherence tomography (OCT) system to identify and monitor changes in the esophageal tissue architecture from RFA. Two different OCT imaging/RFA application protocols were performed using an

Assuntos
Neoplasias Esofágicas/cirurgia , Esofagoscopia/instrumentação , Tomografia de Coerência Óptica , Ablação por Cateter , Humanos , Resultado do Tratamento
18.
Int Med Case Rep J ; 10: 143-148, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28458585

RESUMO

BACKGROUND: Laser in situ keratomileusis (LASIK) is the most common and popular procedure performed for the correction of refractive errors in the last two decades. We report a case of traumatic flap displacement with flap folding which occurred 3 years after LASIK was performed. Previous literature suggests that vision prognosis would be closely related to proper and prompt management of traumatic flap displacement with flap folding 3 years after LASIK. CASE PRESENTATION: A 23-year-old female presented to our hospital who had undergone uneventful LASIK in both eyes 3 years prior. Unfortunately, she had suffered a blunt trauma in her right eye in a car accident. A late onset of corneal flap displacement was found with upper and lower portion of the flap being folded inside the corneal bed. Surgical intervention for debridement with subsequent reposition of corneal flap was performed as soon as possible in the operating room. A bandage contact lens was placed, and topical antibiotic and corticosteroids were given postoperatively. Two days after the operation, the displaced corneal flap was found to be well attached smoothly on the corneal bed without folds. The best-corrected visual acuity was 6/6 with refraction of -0.75 D to 1.0 D ×175° in her right eye 1 month later. LITERATURE REVIEW: We reviewed a total of 19 published cases of late-onset traumatic flap dislocations or displacements after LASIK with complete data from 2000 to 2014. CONCLUSION: Traumatic displacement of corneal flaps after LASIK may occur after blunt injury with specific direction of force to the flap margin, especially tangential one. According to the previous literature, late-onset traumatic flap displacement may happen at any time after LASIK and be caused by various types of injuries. Fortunately, good visual function could mostly be restored with immediate and proper management.

19.
Angew Chem Int Ed Engl ; 56(18): 5001-5006, 2017 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-28370916

RESUMO

Materials which selectively transport molecules along defined paths offer new opportunities for concentrating, processing and sensing chemical and biological agents. Here, we present the use of traveling ionic waves to drive molecular transport and concentration of hydrophilic molecules entrained within a hydrogel. The traveling ionic wave is triggered by the spatially localized introduction of ions, which through a dissipative ion exchange process, converts quaternary ammonium groups in the hydrogel from hydrophilic to hydrophobic. Through a reaction-diffusion process, the hydrophobic region expands with a sharp transition at the leading edge; it is this sharp gradient in hydrophilicity that drives the transport of hydrophilic molecules dispersed within the film. The traveling wave moved up to 450 µm within 30 min, while the gradient length remained 20 µm over this time. As an example of the potential of molecular concentration using this approach, a 70-fold concentration of a hydrophilic dye was demonstrated.

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