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1.
Proc Natl Acad Sci U S A ; 119(24): e2200830119, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35679344

RESUMO

The functional support and advancement of our body while preserving inherent naturalness is one of the ultimate goals of bioengineering. Skin protection against infectious pathogens is an application that requires common and long-term wear without discomfort or distortion of the skin functions. However, no antimicrobial method has been introduced to prevent cross-infection while preserving intrinsic skin conditions. Here, we propose an antimicrobial skin protection platform copper nanomesh, which prevents cross-infectionmorphology, temperature change rate, and skin humidity. Copper nanomesh exhibited an inactivation rate of 99.99% for Escherichia coli bacteria and influenza virus A within 1 and 10 min, respectively. The thin and porous nanomesh allows for conformal coating on the fingertips, without significant interference with the rate of skin temperature change and humidity. Efficient cross-infection prevention and thermal transfer of copper nanomesh were demonstrated using direct on-hand experiments.


Assuntos
Anti-Infecciosos , Cobre , Infecção Hospitalar , Nanopartículas Metálicas , Pele , Anti-Infecciosos/farmacologia , Cobre/farmacologia , Infecção Hospitalar/prevenção & controle , Escherichia coli/efeitos dos fármacos , Dedos , Humanos , Vírus da Influenza A/efeitos dos fármacos , Porosidade , Pele/microbiologia
2.
BMC Cancer ; 24(1): 252, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395832

RESUMO

BACKGROUND: Immune checkpoint inhibitor (ICI) or irinotecan-based chemotherapy is frequently used after failure of second-line paclitaxel plus ramucirumab treatment for patients with locally advanced unresectable or metastatic advanced gastric cancer (AGC). This study aimed to compare the efficacy between ICI and irinotecan-based chemotherapy as third-line treatment in patients with AGC. METHODS: We retrospectively reviewed patients with AGC, whose third-line treatment started between July 2019 and June 2021 at 17 institutions in Korea. The ICI group included patients who received nivolumab or pembrolizumab, and the irinotecan-based chemotherapy group included patients who received irinotecan or FOLFIRI (5-fluorouracil, leucovorin and irinotecan). RESULTS: A total of 363 patients [n = 129 (ICI) and n = 234 (irinotecan-based chemotherapy)] were analyzed. The median progression-free survival was 2.3 and 2.9 months in ICI and irinotecan-based chemotherapy groups, respectively (p = 0.802). The median overall survival (OS) was 5.5 and 6.0 months in ICI and irinotecan-based chemotherapy groups, respectively (p = 0.786). For all patients included in this study, multivariable analysis showed that weight loss, peritoneal metastasis, low serum sodium or albumin, and short duration of second-line treatment were associated with inferior OS (p < 0.05). ICI showed significantly longer OS than irinotecan-based chemotherapy in patients without peritoneal metastasis. Whereas ICI showed significantly shorter OS in patients without PD-L1 expression than irinotecan-based chemotherapy. CONCLUSIONS: No significant difference in survival outcome was observed between ICI and irinotecan-based chemotherapy as third-line treatment for AGC patients. ICI might be preferred for patients without peritoneal metastasis and irinotecan-based chemotherapy for patients with tumors without PD-L1 expression. TRIAL REGISTRATION: This study was registered in the Clinical Trial Registry of Korea ( https://cris.nih.go.kr : KCT 0007732).


Assuntos
Niacinamida/análogos & derivados , Neoplasias Peritoneais , Neoplasias Gástricas , Humanos , Irinotecano , Neoplasias Gástricas/patologia , Inibidores de Checkpoint Imunológico/efeitos adversos , Antígeno B7-H1 , Camptotecina , Estudos Retrospectivos , Neoplasias Peritoneais/tratamento farmacológico , Fluoruracila , Leucovorina , República da Coreia/epidemiologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
Proc Natl Acad Sci U S A ; 118(38)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34518214

RESUMO

Robust polymeric nanofilms can be used to construct gas-permeable soft electronics that can directly adhere to soft biological tissue for continuous, long-term biosignal monitoring. However, it is challenging to fabricate gas-permeable dry electrodes that can self-adhere to the human skin and retain their functionality for long-term (>1 d) health monitoring. We have succeeded in developing an extraordinarily robust, self-adhesive, gas-permeable nanofilm with a thickness of only 95 nm. It exhibits an extremely high skin adhesion energy per unit area of 159 µJ/cm2 The nanofilm can self-adhere to the human skin by van der Waals forces alone, for 1 wk, without any adhesive materials or tapes. The nanofilm is ultradurable, and it can support liquids that are 79,000 times heavier than its own weight with a tensile stress of 7.82 MPa. The advantageous features of its thinness, self-adhesiveness, and robustness enable a gas-permeable dry electrode comprising of a nanofilm and an Au layer, resulting in a continuous monitoring of electrocardiogram signals with a high signal-to-noise ratio (34 dB) for 1 wk.

4.
Cancer ; 129(19): 2966-2974, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37246414

RESUMO

BACKGROUND: Salivary duct carcinoma (SDC) is uncommon but is the most aggressive subtype of salivary gland carcinomas. The high positivity rate for human epidermal growth factor receptor 2 (HER2) led to an investigation of the efficacy of HER2-targeted agents. Docetaxel-PM (polymeric micelle) is a low-molecular-weight, nontoxic, biodegradable, and docetaxel-loaded micellar formulation. Trastuzumab-pkrb is a biosimilar to trastuzumab. METHODS: This was a multicenter, single-arm, open-label phase 2 study. Patients with HER2-positive (immunohistochemistry [IHC] score of ≥2+ and/or HER2/chromosome enumeration probe 17 [CEP17] ratio of ≥2.0) advanced SDCs were enrolled. Patients received docetaxel-PM (75 mg/m2 ) and trastuzumab-pkrb (8 mg/kg in the first cycle and 6 mg/kg in subsequent cycles) every 3 weeks. Primary end point was objective response rate (ORR). RESULTS: A total of 43 patients were enrolled. The best objective responses were partial response in 30 (69.8%) patients and stable disease in 10 (23.3%) patients, leading to an ORR of 69.8% (95% confidence interval [CI], 53.9-82.8) and a disease control rate of 93.0% (80.9-98.5). Median progression-free survival, duration of response, and overall survival were 7.9 (6.3-9.5), 6.7 (5.1-8.4), and 23.3 (19.9-26.7) months, respectively. Patients with HER2 IHC score of 3+ or HER2/CEP17 ratio ≥2.0 demonstrated better efficacies compared to those with HER2 IHC score of 2+. Thirty-eight (88.4%) patients experienced treatment-related adverse events (TRAE). Because of TRAE, nine (20.9%), 14 (32.6%), and 19 (44.2%) patients required temporary discontinuation, permanent discontinuation, or dose reduction, respectively. CONCLUSIONS: The combination of docetaxel-PM and trastuzumab-pkrb demonstrated promising antitumor activity with a manageable toxicity profile in HER2-positive advanced SDC. PLAIN LANGUAGE SUMMARY: Salivary duct carcinoma (SDC) is uncommon but is the most aggressive subtype of salivary gland carcinomas. SDC shares morphological and histological similarities with invasive ductal carcinoma of breast, which led to an investigation of hormonal receptor and human epidermal growth factor receptor 2 (HER2)/neu expression status in SDC. In this study, patients with HER2-positive SDC were enrolled and treated with combination of docetaxel-polymeric micelle and trastuzumab-pkrb. Promising antitumor activities were shown with objective response rate of 69.8%, disease control rate of 93.0%, median progression-free survival of 7.9 months, median duration of response of 6.7 months, and median overall survival of 23.3 months.


Assuntos
Neoplasias da Mama , Carcinoma Ductal , Humanos , Feminino , Docetaxel/uso terapêutico , Micelas , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Trastuzumab/uso terapêutico , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Glândulas Salivares/metabolismo , Neoplasias da Mama/tratamento farmacológico
5.
Small ; 18(48): e2204078, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36180411

RESUMO

The demand for power-efficient micro-and nanodevices is increasing rapidly. In this regard, electrothermal nanowire-based heaters are promising solutions for the ultralow-power devices required in IoT applications. Herein, a method is demonstrated for producing a 1D nanoheater by selectively coating a suspended pyrolyzed carbon nanowire backbone with a thin Au resistive heater layer and utilizing it in a portable gas sensor system. This sophisticated nanostructure is developed without complex nanofabrication and nanoscale alignment processes, owing to the suspended architecture and built-in shadow mask. The suspended carbon nanowires, which are batch-fabricated using carbon-microelectromechanical systems technology, maintain their structural and functional integrity in subsequent nanopatterning processes because of their excellent mechanical robustness. The developed nanoheater is used in gas sensors via user-designable localization of the metal oxide semiconductor nanomaterials onto the central region of the nanoheater at the desired temperature. This allows the sensing site to be uniformly heated, enabling reliable and sensitive gas detection. The 1D nanoheater embedded gas sensor can be heated immediately to 250 °C at a remarkably low power of 1.6 mW, surpassing the performance of state-of-the-art microheater-based gas sensors. The presented technology offers facile 1D nanoheater production and promising pathways for applications in various electrothermal devices.

6.
Oncology ; 99(8): 499-506, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34098565

RESUMO

PURPOSE: The BRCA1/2 gene is the most well-known and studied gene associated with hereditary breast cancer. BRCA1/2 genetic testing is widely performed in high-risk patients of hereditary breast cancer in Korea. This study aimed to investigate the clinicopathological characteristics of BRCA1/2 mutation-positive breast cancer patients. METHODS: The clinical data of 188 Korean breast cancer patients who underwent genetic testing of BRCA1/2 mutation between March 2015 and February 2020 at Pusan National University Yangsan Hospital were retrospectively reviewed. The characteristics of breast cancer according to the expression of BRCA1 and BRCA2 mutations were analyzed using the Health Insurance Review and Assessment Service guideline criteria and other clinicopathological factors. RESULTS: The factor associated with BRCA1/2 gene expression was cancer stage, and mutation expression was significantly decreased in stage I compared to stage 0 (p = 0.033; odds ratio [OR], 0.169; 95% confidence interval [CI], 0.033-0.867), and there was a tendency to increase in stage II (p = 0.780; OR, 1.150; 95% CI, 0.432-3.064). BRCA1 was significantly associated with triple-negative breast cancer (TNBC) (p = 0.004; OR, 5.887; 95% CI, 1.778-19.498). Gene expression of BRCA2 was significantly reduced under 40 years of age (p = 0.040; OR, 0.198; 95% CI, 0.042-0.930). There was no difference in disease-free survival (p = 0.900) and overall survival (p = 0.733) between the BRCA1/2 mutation-positive and -negative groups. CONCLUSION: In this study, the clinicopathological characteristics of breast cancer patients with BRCA1/2 gene mutations were identified. BRCA1 gene expression was highly correlated with TNBC. BRCA1/2 mutation did not have a poor prognosis regarding recurrence and death.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Genes BRCA1 , Genes BRCA2 , Mutação , Adulto , Fatores Etários , Proteína BRCA1/biossíntese , Neoplasias da Mama/metabolismo , Feminino , Expressão Gênica , Testes Genéticos , Humanos , Imuno-Histoquímica , Estadiamento de Neoplasias , República da Coreia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
7.
Oncologist ; 24(11): e1212-e1218, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31036770

RESUMO

BACKGROUND: Regorafenib at the standard intermittent dosing schedule proved effective in the GRID trial for refractory gastrointestinal stromal tumors (GISTs). However, this dosing schedule requires frequent dose reduction, and the progression of GISTs or tumor-related symptoms during the off-treatment period has also been noted in some patients. Therefore, we conducted this phase II trial to evaluate the efficacy and safety of regorafenib at a lower dose on a continuous dosing schedule. METHODS: Patients with measurable, metastatic, or recurrent GISTs who failed to respond to both imatinib and sunitinib were eligible for this study. Regorafenib 100 mg p.o. daily was administered continuously. The primary endpoint was disease control rate (DCR: complete response plus partial response [PR] plus stable disease [SD]) lasting for at least 12 weeks using RECIST version 1.1. RESULTS: The best response was PR in 2 (8%), SD in 16 (64%), and progressive disease in 6 (24%) patients. DCR lasting for at least 12 weeks was 64% (16 of 25). The median progression-free survival was 7.3 months (95% confidence interval, 5.9-8.6), and the 1-year survival rate was 64.5%. Ten patients (40%) experienced grade 3-4 toxicities, including hand-foot skin reaction (n = 4, 16%) and elevation of alanine aminotransferase (n = 2, 8%). Only six patients (24%) needed dose modification with a relative dose intensity of 95.0% for eight cycles in all patients. CONCLUSION: Regorafenib at a lower dose on a continuous schedule might be an alternative treatment in patients with GISTs after failure of imatinib and sunitinib. Clinical trial identification number. NCT02889328 IMPLICATIONS FOR PRACTICE: Regorafenib at the standard intermittent dosing schedule proved effective in the GRID trial for refractory gastrointestinal stromal tumors (GISTs). However, this dosing schedule requires frequent dose reduction, and the progression of GISTs or tumor-related symptoms during the off-treatment period has been noted in some patients. This study was to evaluate the efficacy and safety of regorafenib at a lower dose on a continuous dosing schedule. With good efficacy and acceptable safety profiles, regorafenib at a lower, continuously administered dose might be an alternative treatment in patients with GISTs after imatinib and sunitinib. Rechallenge of regorafenib may slow the disease progression.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Terapia de Salvação , Adulto , Idoso , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/patologia , Humanos , Mesilato de Imatinib/administração & dosagem , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Ensaios Clínicos Controlados não Aleatórios como Assunto , Compostos de Fenilureia/administração & dosagem , Prognóstico , Piridinas/administração & dosagem , Sunitinibe/administração & dosagem , Taxa de Sobrevida
8.
Acc Chem Res ; 51(4): 850-859, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29521501

RESUMO

Body-mountable electronics and electronically active garments are the future of portable, interactive devices. However, wearable devices and electronic garments are demanding technology platforms because of the large, varied mechanical stresses to which they are routinely subjected, which can easily abrade or damage microelectronic components and electronic interconnects. Furthermore, aesthetics and tactile perception (or feel) can make or break a nascent wearable technology, irrespective of device metrics. The breathability and comfort of commercial fabrics is unmatched. There is strong motivation to use something that is already familiar, such as cotton/silk thread, fabrics, and clothes, and imperceptibly adapt it to a new technological application. (24) Especially for smart garments, the intrinsic breathability, comfort, and feel of familiar fabrics cannot be replicated by devices built on metalized synthetic fabrics or cladded, often-heavy designer fibers. We propose that the strongest strategy to create long-lasting and impactful electronic garments is to start with a mass-produced article of clothing, fabric, or thread/yarn and coat it with conjugated polymers to yield various textile circuit components. Commonly available, mass-produced fabrics, yarns/threads, and premade garments can in theory be transformed into a plethora of comfortably wearable electronic devices upon being coated with films of electronically active conjugated polymers. The definitive hurdle is that premade garments, threads, and fabrics have densely textured, three-dimensional surfaces that display roughness over a large range of length scales, from microns to millimeters. Tremendous variation in the surface morphology of conjugated-polymer-coated fibers and fabrics can be observed with different coating or processing conditions. In turn, the morphology of the conjugated polymer active layer determines the electrical performance and, most importantly, the device ruggedness and lifetime. Reactive vapor coating methods allow a conjugated polymer film to be directly formed on the surface of any premade garment, prewoven fabric, or fiber/yarn substrate without the need for specialized processing conditions, surface pretreatments, detergents, or fixing agents. This feature allows electronic coatings to be applied at the end of existing, high-throughput textile and garment manufacturing routines, irrespective of dye content or surface finish of the final textile. Furthermore, reactive vapor coating produces conductive materials without any insulating moieties and yields uniform and conformal films on fiber/fabric surfaces that are notably wash- and wear-stable and can withstand mechanically demanding textile manufacturing routines. These unique features mean that rugged and practical textile electronic devices can be created using sewing, weaving, or knitting procedures without compromising or otherwise affecting the surface electronic coating. In this Account, we highlight selected electronic fabrics and garments created by melding reactive vapor deposition with traditional textile manipulation processes, including electrically heated gloves that are lightweight, breathable, and sweat-resistant; surface-coated cotton, silk, and bast fiber threads capable of carrying large current densities and acting as sewable circuit interconnects; and surface-coated nylon threads woven together to form triboelectric textiles that can convert surface charge created during small body movements into usable and storable power.


Assuntos
Nylons/química , Indústria Têxtil , Têxteis , Dispositivos Eletrônicos Vestíveis , Volatilização
9.
Opt Express ; 27(25): 36708-36716, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873444

RESUMO

The effect of magnetic fields on the optical output power of flip-chip light-emitting diodes (LEDs) with InGaN/GaN multiple quantum wells (MQWs) was investigated. Films and circular disks comprising ferromagnetic cobalt/platinum (Co/Pt) multilayers were deposited on a p-ohmic reflector to apply magnetic fields in the direction perpendicular to the MQWs of the LEDs. At an injection current of 20 mA, the ferromagnetic Co/Pt multilayer film increased the optical output power of the LED by 20% compared to an LED without a ferromagnetic Co/Pt multilayer. Furthermore, the optical output power of the LED with circular disks was 40% higher at 20 mA than the output of the LED with a film. The increase of the optical output power of the LEDs featuring ferromagnetic Co/Pt multilayers is attributed to the magnetic field gradient in the MQWs, which increases the carrier path in the MQWs. The time-resolved photoluminescence measurement indicates that the improvement of optical output power is owing to an enhanced radiative recombination rate of the carriers in the MQWs as a result of the magnetic field gradient from the ferromagnetic Co/Pt multilayer.

10.
Nanotechnology ; 29(11): 115203, 2018 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-29328054

RESUMO

To improve the classification accuracy of an image data set (CIFAR-10) by using analog input voltage, synapse devices with excellent conductance linearity (CL) and multi-level cell (MLC) characteristics are required. We analyze the CL and MLC characteristics of TaOx-based filamentary resistive random access memory (RRAM) to implement the synapse device in neural network hardware. Our findings show that the number of oxygen vacancies in the filament constriction region of the RRAM directly controls the CL and MLC characteristics. By adopting a Ta electrode (instead of Ti) and the hot-forming step, we could form a dense conductive filament. As a result, a wide range of conductance levels with CL is achieved and significantly improved image classification accuracy is confirmed.


Assuntos
Condutividade Elétrica , Redes Neurais de Computação , Óxidos/química , Reconhecimento Automatizado de Padrão , Tantálio/química
11.
Sensors (Basel) ; 18(11)2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30405069

RESUMO

This paper presents a portable magnetic induction tomography (MIT) transceiver integrated circuit to miniaturize conventional equipment-based MIT systems. The miniaturized MIT function is enabled through single-chip transceiver implementation. The proposed MIT transceiver utilizes a phase-locked loop (PLL) for frequency sweeping and a phase-domain sigma⁻delta modulator with phase-band auto-tracking for a full-range fine-phase resolution. The designed transceiver is fabricated and verified to achieve the measured signal to noise and distortion ratio (SNDR) of 101.7 dB. Its system-level prototype including in-house magnetic sensor coils is manufactured and functionally verified for four different material types.

12.
Sensors (Basel) ; 18(3)2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29498686

RESUMO

This paper presents a resolution-reconfigurable wide-range resistive sensor readout interface for wireless multi-gas monitoring applications that displays results on a smartphone. Three types of sensing resolutions were selected to minimize processing power consumption, and a dual-mode front-end structure was proposed to support the detection of a variety of hazardous gases with wide range of characteristic resistance. The readout integrated circuit (ROIC) was fabricated in a 0.18 µm CMOS process to provide three reconfigurable data conversions that correspond to a low-power resistance-to-digital converter (RDC), a 12-bit successive approximation register (SAR) analog-to-digital converter (ADC), and a 16-bit delta-sigma modulator. For functional feasibility, a wireless sensor system prototype that included in-house microelectromechanical (MEMS) sensing devices and commercial device products was manufactured and experimentally verified to detect a variety of hazardous gases.

13.
Nano Lett ; 17(5): 3040-3046, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28394623

RESUMO

The smooth surface of crystalline rubrene films formed through an abrupt heating process provides a valuable platform to study organic homoepitaxy. By varying growth rate and substrate temperature, we are able to manipulate the onset of a transition from layer-by-layer to island growth modes, while the crystalline thin films maintain a remarkably smooth surface (less than 2.3 nm root-mean-square roughness) even with thick (80 nm) adlayers. We also uncover evidence of point and line defect formation in these films, indicating that homoepitaxy under our conditions is not at equilibrium or strain-free. Point defects that are resolved as screw dislocations can be eliminated under closer-to-equilibrium conditions, whereas we are not able to eliminate the formation of line defects within our experimental constraints at adlayer thicknesses above ∼25 nm. We are, however, able to eliminate these line defects by growing on a bulk single crystal of rubrene, indicating that the line defects are a result of strain built into the thin film template. We utilize electron backscatter diffraction, which is a first for organics, to investigate the origin of these line defects and find that they preferentially occur parallel to the (002) plane, which is in agreement with expectations based on calculated surface energies of various rubrene crystal facets. By combining the benefits of crystallinity, low surface roughness, and thickness-tunability, this system provides an important study of attributes valuable to high-performance organic electronic devices.

14.
Sensors (Basel) ; 17(4)2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28368355

RESUMO

This paper presents a reconfigurable multi-sensor interface and its readout integrated circuit (ROIC) for display-based multi-sensor systems, which builds up multi-sensor functions by utilizing touch screen panels. In addition to inherent touch detection, physiological and environmental sensor interfaces are incorporated. The reconfigurable feature is effectively implemented by proposing two basis readout topologies of amplifier-based and oscillator-based circuits. For noise-immune design against various noises from inherent human-touch operations, an alternate-sampling error-correction scheme is proposed and integrated inside the ROIC, achieving a 12-bit resolution of successive approximation register (SAR) of analog-to-digital conversion without additional calibrations. A ROIC prototype that includes the whole proposed functions and data converters was fabricated in a 0.18 µm complementary metal oxide semiconductor (CMOS) process, and its feasibility was experimentally verified to support multiple heterogeneous sensing functions of touch, electrocardiogram, body impedance, and environmental sensors.

15.
Sensors (Basel) ; 18(1)2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29286312

RESUMO

This study presents a flexible wireless electronic skin (e-skin) sensor system that includes a multi-functional sensor device, a triple-mode reconfigurable readout integrated circuit (ROIC), and a mobile monitoring interface. The e-skin device's multi-functionality is achieved by an interlocked micro-dome array structure that uses a polyvinylidene fluoride and reduced graphene oxide (PVDF/RGO) composite material that is inspired by the structure and functions of the human fingertip. For multi-functional implementation, the proposed triple-mode ROIC is reconfigured to support piezoelectric, piezoresistance, and pyroelectric interfaces through single-type e-skin sensor devices. A flexible system prototype was developed and experimentally verified to provide various wireless wearable sensing functions-including pulse wave, voice, chewing/swallowing, breathing, knee movements, and temperature-while their real-time sensed data are displayed on a smartphone.


Assuntos
Pele , Grafite , Frequência Cardíaca , Humanos , Movimento , Dispositivos Eletrônicos Vestíveis
16.
Sensors (Basel) ; 17(8)2017 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-28813017

RESUMO

This paper presents a wearable electrophysiological interface with enhanced immunity to motion artifacts. Anti-artifact schemes, including a patch-type modular structure and real-time automatic level adjustment, are proposed and verified in two wireless system prototypes of a patch-type electrocardiogram (ECG) module and an electromyogram (EMG)-based robot-hand controller. Their common ExG readout integrated circuit (ROIC), which is reconfigurable for multiple physiological interfaces, is designed and fabricated in a 0.18 µm CMOS process. Moreover, analog pre-processing structures based on envelope detection are integrated with one another to mitigate signal processing burdens in the digital domain effectively.


Assuntos
Robótica , Eletrocardiografia , Eletromiografia , Desenho de Equipamento , Processamento de Sinais Assistido por Computador
17.
Emerg Infect Dis ; 21(7): 1247-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26079171

RESUMO

We investigated an October 2014 outbreak of illness caused by Shigella sonnei in a daycare center in the Republic of Korea (South Korea). The outbreak strain was resistant to extended-spectrum cephalosporins and fluoroquinolones and was traced to a child who had traveled to Vietnam. Improved hygiene and infection control practices are needed for prevention of shigellosis.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacina/farmacologia , Surtos de Doenças , Disenteria Bacilar/tratamento farmacológico , Shigella sonnei/efeitos dos fármacos , Adolescente , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Ciprofloxacina/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Disenteria Bacilar/epidemiologia , Disenteria Bacilar/microbiologia , Feminino , Genes Bacterianos , Humanos , Masculino , República da Coreia/epidemiologia , Viagem , Vietnã , Resistência beta-Lactâmica
18.
Nanotechnology ; 26(38): 385204, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26335045

RESUMO

We report on the characteristics of localized surface plasmon (LSP)-enhanced near-ultraviolet light-emitting diodes (NUV-LEDs) fabricated by using colloidal silver (Ag) nanoparticles (NPs). Colloidal Ag NPs were deposited on the 20 nm thick p-GaN spacer layer using a spray process. The optical output power of NUV-LEDs with colloidal Ag NPs was increased by 48.7% at 20 mA compared with NUV-LEDs without colloidal Ag NPs. The enhancement was attributed to increased internal quantum efficiency caused by the resonance coupling between excitons in the multiple quantum wells and the LSPs in the Ag NPs.

19.
Opt Express ; 22 Suppl 4: A1164-73, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24978079

RESUMO

We demonstrate the high efficiency of InGaN/GaN multiple quantum wells (MQWs) light-emitting diode (LED) grown on the electrochemically etched nanoporous (NP) GaN. The photoluminescence (PL) and Raman spectra show that the LEDs with NP GaN have a strong carrier localization effect resulting from the relaxed strain and reduced defect density in MQWs. Also, the finite-difference time-domain (FDTD) simulation shows that the light extraction efficiency (LEE) is increased by light scattering effect by nanopores. The output power of LED with NP GaN is increased up to 123.1% at 20 mA, compared to that of LED without NP GaN. The outstanding performance of LEDs with NP GaN is attributed to the increased internal quantum efficiency (IQE) by the carrier localization in the indium-rich clusters, low defect density in MQWs, and increased LEE owing to the light scattering in NP GaN.

20.
Phys Chem Chem Phys ; 16(43): 23985-92, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25285782

RESUMO

Hydrogen storage and release are two essential parameters that define the efficiency of a hydrogen storage medium. Herein, we investigate the effects of the external electric field F on the adsorption-desorption of H2 on a Ca-decorated silicene system (Ca-silicene) based on density functional theory calculations. Our study demonstrates that nine H2 molecules per Ca atom can be adsorbed and 6.4 wt% H2 can be adsorbed on Ca-silicene with an average binding energy of 0.19 eV per H2, while the appropriate F can be used to effectively enhance the hydrogen storage-release on the Ca-silicene system. The high synergetic effect may be attributed to the observation that F induces an enhancement of the charge transfer between H2 molecules and the Ca-silicene system. Thus, the Ca-silicene system together with the synergy of F can efficiently facilitate H2 adsorption-desorption, completing the whole hydrogen storage-release cycle.

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