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Oriental lacquer sap is attracting considerable attention as a renewable and eco-friendly natural resin with high durability, heat resistance, insulation, insect repellency, and antiseptic and antibacterial properties. However, to ensure excellent coating performance, it is necessary to improve the drying/curing process of lacquer sap with a time-consuming drying time at high humidity [relative humidity (RH), 70-90%] and ambient temperature (20-30 °C). Drawing on an understanding of the polymerization mechanism of urushiol, the main component of the lacquer sap consisted of a water-in-oil (W/O) emulsion, and this study presents an eco-friendly additive that mimics the structure-function of urushiol composed of a polar catechol head group and a nonpolar hydrocarbon tail. A photo-curable lacquer sap was thus developed by adding a tyrosine amino acid-based lipid agent (denoted as Y-ADDA), which allows faster and more effective drying/curing at lower humidity while maintaining the nature-derived properties of lacquer sap. Y-ADDA easily coassembles with urushiol in the W/O emulsion droplets, thereby significantly accelerating the formation of a polymer network along with urushiol during water evaporation leading to fast drying/curing under ultraviolet (UV) light irradiation at low humidity (â¼50% RH). The UV-cured lacquer sap resins showed higher performance in terms of film processing and physicochemical properties compared with that of the lacquer containing only tyrosine amino acids without aliphatic tail conjugation, N-(9-fluorenylmethoxycarbonyl)-O-tert-butyl-l-tyrosine Fmoc-Tyr(tBu)-OH. Furthermore, the drying and curing times, film morphology, transmittance, hardness, and adhesion strength of the UV-cured lacquer were markedly superior compared to those of shellac, a general eco-friendly fast-drying primer. The study provides useful strategies and insights to promote the industrial application of lacquer sap resins by employing biocompatible nanoagents developed with an understanding of the curing mechanism of natural resins and from the viewpoint of green and sustainable chemistry perspective.
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Laca , Tirosina , Catecóis , Emulsões , ÁguaRESUMO
The effect of chemical-composition modification on the chiroptical property of chiral organic ammonium cation-containing organic inorganic hybrid perovskite (chiral OIHP) is investigated. Varying the mixing ratio of bromide and iodide anions in S- or R-C6H5CH2(CH3)NH3)2PbI4(1-x)Br4x modifies the band gap of chiral OIHP, leading to a shift of the circular dichroism (CD) signal from 495 to 474 nm. However, it is also found that an abrupt crystalline structure transition occurs, and the CD signal is turned off when iodide-determinant phases are transformed into the bromide-determinant phase. To obtain CD in the wavelength range where the bromide-determinant phase is supposed to exhibit chiroptical activity, that is, <474 nm, S- or R-C12H7CH2(CH3)NH3 with a larger spacer group can be adopted; thus, the CD signal can be further blue-shifted to â¼375 nm. Here, we show that chemical-composition modification of chiral OIHP affects the chiroptical properties of chiral OIHP in two ways: (1) tuning the wavelength of CD by modulating the excitonic band structure and (2) switching the CD on and off by inducing a crystalline-structure change. These properties can be utilized for structural engineering of high-performance chiroptical materials for spin-polarized light-emitting devices and polarization-based optoelectronics.
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OBJECTIVE: There is no scale for rating the severity of autoimmune encephalitis (AE). In this study, we aimed to develop a novel scale for rating severity in patients with diverse AE syndromes and to verify the reliability and validity of the developed scale. METHODS: The key items were generated by a panel of experts and selected according to content validity ratios. The developed scale was initially applied to 50 patients with AE (development cohort) to evaluate its acceptability, reproducibility, internal consistency, and construct validity. Then, the scale was applied to another independent cohort (validation cohort, n = 38). RESULTS: A new scale consisting of 9 items (seizure, memory dysfunction, psychiatric symptoms, consciousness, language problems, dyskinesia/dystonia, gait instability and ataxia, brainstem dysfunction, and weakness) was developed. Each item was assigned a value of up to 3 points. The total score could therefore range from 0 to 27. We named the scale the Clinical Assessment Scale in Autoimmune Encephalitis (CASE). The new scale showed excellent interobserver (intraclass correlation coefficient [ICC] = 0.97) and intraobserver (ICC = 0.96) reliability for total scores, was highly correlated with modified Rankin scale (r = 0.86, p < 0.001), and had acceptable internal consistency (Cronbach α = 0.88). Additionally, in the validation cohort, the scale showed high interobserver reliability (ICC = 0.99) and internal consistency (Cronbach α = 0.92). INTERPRETATION: CASE is a novel clinical scale for AE with a high level of clinimetric properties. It would be suitable for application in clinical practice and might help overcome the limitations of current outcome scales for AE. ANN NEUROL 2019;85:352-358.
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Doenças Autoimunes do Sistema Nervoso/fisiopatologia , Doenças Autoimunes do Sistema Nervoso/psicologia , Encefalite/fisiopatologia , Encefalite/psicologia , Adolescente , Adulto , Idoso , Agressão/psicologia , Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Encefalite Antirreceptor de N-Metil-D-Aspartato/fisiopatologia , Encefalite Antirreceptor de N-Metil-D-Aspartato/psicologia , Ataxia/etiologia , Ataxia/fisiopatologia , Doenças Autoimunes/complicações , Doenças Autoimunes/fisiopatologia , Doenças Autoimunes/psicologia , Doenças Autoimunes do Sistema Nervoso/complicações , Delusões/psicologia , Discinesias/etiologia , Discinesias/fisiopatologia , Distonia/etiologia , Distonia/fisiopatologia , Encefalite/complicações , Encefalomielite Aguda Disseminada/complicações , Encefalomielite Aguda Disseminada/fisiopatologia , Encefalomielite Aguda Disseminada/psicologia , Feminino , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Alucinações/psicologia , Humanos , Transtornos da Linguagem/etiologia , Transtornos da Linguagem/fisiopatologia , Encefalite Límbica/complicações , Encefalite Límbica/fisiopatologia , Encefalite Límbica/psicologia , Masculino , Transtornos da Memória/etiologia , Transtornos da Memória/fisiopatologia , Pessoa de Meia-Idade , Debilidade Muscular/etiologia , Debilidade Muscular/fisiopatologia , Reprodutibilidade dos Testes , Convulsões/etiologia , Convulsões/fisiopatologia , Índice de Gravidade de Doença , Adulto JovemRESUMO
Transfer-printing enables the assembly of functional nanomaterials on unconventional substrates with a desired layout in a controllable manner. However, transfer-printing to substrates with complex surfaces remains a challenge. Herein, we show that hydrogels serve as effective template material platforms for the assembly and transfer-printing of conductive nanonetwork patterns for flexible sensors on various topographic surfaces in a very simple yet versatile manner. The non-adherence, nanoporous structure, and molding capability of the hydrophilic hydrogel enable the assembly of conductive nanonetwork patterns on the hydrogel surface and transfer of the nanonetworks onto various flexible and topographic substrates. Flexible strain sensors and pressure sensors that monitor finger motions and arterial pulses are successfully demonstrated using the hydrogel-templated approach. The rich chemistry of polymeric networks, facile molding capability, and biocompatibility of hydrogels could be further combined with additive technology for hydrogels and electronic materials for emerging four-dimensional functional materials and soft bioelectronics.
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OBJECTIVE: Autoimmune encephalitis (AE), represented by anti-leucine-rich glioma-inactivated 1 (anti-LGI1) and anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis, has increasing clinical significance based on recent discoveries of neuronal autoantibodies. However, its immunopathogenesis is not fully understood. Here, we investigated whether AE is associated with the human leukocyte antigen (HLA) subtypes. METHODS: We compared the HLA genotypes of 11 anti-LGI1 and 17 anti-NMDAR encephalitis patients to the control groups, which consisted of 210 epilepsy patients and 485 healthy Koreans. RESULTS: Anti-LGI1 encephalitis was associated with the DRB1*07:01-DQB1*02:02 haplotype (10 patients; 91%) in HLA class II genes, as well as with B*44:03 (8 patients; 73%) and C*07:06 (7 patients; 64%) in the HLA class I region. The prevalence of these alleles in anti-LGI1 encephalitis was significantly higher than that in the epilepsy controls or healthy controls. By contrast, anti-NMDAR encephalitis was not associated with HLA genotypes. Additional analysis using HLA-peptide binding prediction algorithms and computational docking underpinned the close relationship. INTERPRETATION: This finding suggests that most anti-LGI1 encephalitis develops in a population with specific HLA subtypes, providing insight into a novel disease mechanism. Ann Neurol 2017;81:183-192.
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Encefalite/genética , Encefalite/imunologia , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Proteínas/imunologia , Adolescente , Adulto , Idoso , Encefalite Antirreceptor de N-Metil-D-Aspartato/genética , Encefalite Antirreceptor de N-Metil-D-Aspartato/imunologia , Autoanticorpos , Feminino , Haplótipos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Parvovirus B19 (PVB19) has rarely been identified as a cause of encephalitis in immunocompetent adults, in whom clinical information regarding PVB19 encephalitis has remained unclear. Herein, we report the clinical presentations, laboratory and imaging findings, and treatment outcomes of five immunocompetent adults with PVB19 encephalitis. Although none of the patients showed any distinctive features of PVB19 infection, they showed various clinical manifestations, including one instance of brainstem involvement. Additionally, immunotherapy can be considered an effective approach, especially in immunocompetent adults with PVB19 encephalitis who are resistant to the initial management.
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Antivirais/uso terapêutico , Encefalite/tratamento farmacológico , Infecções por Parvoviridae/tratamento farmacológico , Parvovirus B19 Humano/efeitos dos fármacos , Convulsões/tratamento farmacológico , Aciclovir/uso terapêutico , Adulto , Esquema de Medicação , Encefalite/diagnóstico por imagem , Encefalite/imunologia , Encefalite/fisiopatologia , Feminino , Humanos , Imunocompetência , Imunoglobulinas Intravenosas/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Infecções por Parvoviridae/diagnóstico por imagem , Infecções por Parvoviridae/imunologia , Infecções por Parvoviridae/fisiopatologia , Parvovirus B19 Humano/patogenicidade , Parvovirus B19 Humano/fisiologia , Convulsões/diagnóstico por imagem , Convulsões/imunologia , Convulsões/fisiopatologia , Resultado do Tratamento , Carga Viral/efeitos dos fármacosRESUMO
BACKGROUND: Recent reports suggest that mutations in the promoter of the gene encoding telomerase reverse transcriptase (TERT) affect thyroid cancer outcomes. METHODS: In all, 551 patients with differentiated thyroid cancer (DTC) enrolled in this study. The median follow-up duration was 4.8 years (interquartile range, 3.4-10.6 years). RESULTS: TERT promoter mutations were detected in 25 DTCs (4.5%): 2.8% in neither BRAF-mutated nor RAS-mutated tumors, 4.8% in BRAF-mutated tumors, and 11.3% in RAS-mutated tumors. Moreover, they were frequently observed in American Thyroid Association (ATA) high-risk and TNM stage III/IV groups (9.1% and 12.9%, respectively). The coexistence of BRAF or RAS with TERT promoter mutations increased aggressive clinicopathologic features, recurrence (hazard ratio [HR] for BRAF, 4.64; 95% confidence interval [CI], 1.42-15.18; HR for RAS, 5.36; 95% CI, 1.20-24.02), and mortality (HR for BRAF, 15.13; 95% CI, 1.55-148.23; HR for RAS, 14.75; 95% CI, 1.30-167.00), even after adjustments for the age at diagnosis and sex, although the significance was lost after additional adjustments for pathologic characteristics. Furthermore, TERT promoter mutations significantly increased the risk of both recurrence and mortality in the ATA high-risk (HR for recurrence, 5.79; 95% CI, 2.07-16.18; HR for mortality, 16.16; 95% CI, 2.10-124.15) and TNM stage III/IV groups (HR for recurrence, 3.60; 95% CI, 1.19-10.85; HR for mortality, 9.06; 95% CI, 2.09-39.26). CONCLUSIONS: The coexistence of BRAF or RAS mutations enhanced the prognostic effects of TERT promoter mutations. Furthermore, TERT promoter mutations strengthened the predictions of mortality and recurrence by the ATA and TNM staging systems, particularly for high-risk patients with DTC. Cancer 2016;122:1370-1379. © 2016 American Cancer Society.
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Genes ras , Mutação , Recidiva Local de Neoplasia/genética , Proteínas Proto-Oncogênicas B-raf/genética , Telomerase/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Glândula Tireoide/mortalidade , Neoplasias da Glândula Tireoide/patologia , Fatores de TempoRESUMO
OBJECTIVE: Oxcarbazepine (OXC) is a widely used antiepileptic drug for the treatment of partial seizures that was developed through structural variation of carbamazepine. Although OXC has a lower risk of cutaneous adverse drug reactions (cADRs) than carbamazepine, cADRs ranging from maculopapular eruption (MPE) to the more severe Stevens-Johnson syndrome and toxic epidermal necrolysis still limit the use of OXC in some patients. A few human leukocyte antigen (HLA)-related genetic risk factors for carbamazepine-induced cADRs have been identified. However, the HLA-related genetic risk factors associated with OXC-induced cADRs are unknown. METHODS: A total of 40 patients who experienced OXC-induced MPE and 70 patients who were tolerant to OXC treatment were included in the study. Genomic DNA was extracted from the peripheral blood of these patients, and high-resolution HLA genotyping was performed. RESULTS: The HLA-B*40:02 and HLA-DRB1*04:03 alleles were significantly associated with OXC-induced MPE compared with the OXC-tolerant group (odds ratio [OR] 4.33, p = 0.018 and OR 14.64, p = 0.003, respectively) and the general Korean population (OR 4.04, p = 0.001 and OR 3.11, p = 0.019, respectively). The HLA-B*15:01 genetic frequency was significantly lower in the OXC-MPE group compared to the OXC-tolerant group (OR 0.18, p = 0.016) and the Korean population (OR 0.22, p = 0.030). The allele frequencies of well-known HLA-related risk factors for carbamazepine-induced cADRs (HLA-B*15:02, A*31:01 and B*15:11) were not different among the three groups. SIGNIFICANCE: This study is the first to demonstrate an association of HLA-B*40:02 and HLA-DRB1*04:03 with OXC hypersensitivity using a large cohort of patients with OXC-induced MPE. These findings should be confirmed in future studies in different ethnic groups.
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Anticonvulsivantes/efeitos adversos , Carbamazepina/análogos & derivados , Toxidermias/genética , Antígenos HLA-B/genética , Cadeias HLA-DRB1/genética , Adolescente , Adulto , Povo Asiático/genética , Carbamazepina/efeitos adversos , Epilepsia/tratamento farmacológico , Epilepsia/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Oxcarbazepina , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: Patients with postural tachycardia syndrome often appear depressive and report diminished quality of life (QOL). In the current study, we first evaluated if the maximal heart rate (HR) increment after standing is associated with the clinical symptoms in patients with excessive orthostatic tachycardia (OT). Next, we investigated the correlations among the symptoms of orthostatic intolerance (OI), depression, and health-related QOL in these patients. Finally we assessed if patients with minimal OI symptoms suffer from depression or diminished QOL. METHODS: We performed a comprehensive questionnaire-based assessment of symptoms in 107 patients with excessive OT with a ≥ 30 beats/min heart rate increment (or ≥ 40 beats/min in individuals aged between 12 and 19) within 10 min after standing up. An existing orthostatic intolerance questionnaire (OIQ), the Beck depression inventory-II (BDI-II), and the 36 Item Short-Form Health Survey were completed prior to any treatment. Correlation analyses among the items of the questionnaires and other parameters were performed. Additionally, patients with minimal OI symptoms were analysed separately. RESULTS: The maximal orthostatic HR increment was not associated with the clinical symptoms. The OI symptoms were significantly correlated with depression and diminished QOL. The BDI-II score demonstrated a positive linear relationship with total OIQ score (r = 0.516), and both physical and mental component summary scales of SF-36 showed a negative linear relationship with total OIQ score (r = -0.542 and r = -0.440, respectively; all p <0.001). Some OI symptoms were more strongly associated with depression, and others were more strongly related to QOL. Chest discomfort and concentration difficulties were the most influential OI symptoms for depression, while nausea and concentration difficulties were the most influential symptoms for physical and mental QOL, respectively. Dizziness and headache were the two most common complaints in patients with mild to moderate OI symptoms. In addition, subjects with minimal OI symptoms also had considerable deterioration in QOL. CONCLUSION: The OI symptoms, but not the maximal HR increment, are significantly correlated with depression and diminished QOL in patients with excessive OT. Therefore, pervasive history taking is important when encountering patients with excessive OT.
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Depressão/complicações , Frequência Cardíaca/fisiologia , Intolerância Ortostática/etiologia , Intolerância Ortostática/terapia , Síndrome da Taquicardia Postural Ortostática/fisiopatologia , Síndrome da Taquicardia Postural Ortostática/terapia , Qualidade de Vida , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Inquéritos e QuestionáriosRESUMO
Here we demonstrated the split-second crystallization of a liquid-crystalline conjugated polymer semiconductor induced by irradiation with intense pulsed white light (IPWL) for the efficient improvement of electrical properties of flexible thin film transistors. A few seconds of IPWL irradiation of poly(didodecylquaterthiophene-alt-didodecylbithiazole) (PQTBTz-C12) thin films generated heat energy through the photo-thermal effect, leading to the crystallization of PQTBTz-C12 and formation of nodule-like nanostructures. The IPWL-induced crystallization of PQTBTz-C12 resulted in a threefold improvement in the field-effect mobility of thin film transistors compared to as-prepared devices. The conformational change of the PQTBTz-C12 chains was found to be strongly related to the irradiation fluence. As a proof-of-concept, the IPWL treatment was successfully applied to the PQTBTz-C12 layer in flexible transistors based on plastic substrates. The performance of these flexible devices was significantly improved after only 0.6 s of IPWL treatment, without deformation of the plastic substrate.
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Genome-wide profiling has revealed that eukaryotic genomes are transcribed into numerous non-coding RNAs. In particular, long non-coding RNAs (lncRNAs) have been implicated in various human diseases due to their biochemical and functional diversity. Epileptic disorders have been characterized by dysregulation of epigenetic regulatory mechanisms, and recent studies have identified several lncRNAs involved in neural development and network function. However, comprehensive profiling of lncRNAs implicated in chronic epilepsy has been lacking. In this study, microarray analysis was performed to obtain the expression profile of lncRNAs dysregulated in pilocarpine and kainate models, two models of temporal lobe epilepsy commonly used for studying epileptic mechanisms. Total of 4622 lncRNAs were analyzed: 384 lncRNAs were significantly dysregulated in pilocarpine model, and 279 lncRNAs were significantly dysregulated in kainate model compared with control mice (≥3.0-fold, p < 0.05). Among these, 54 and 14 lncRNAs, respectively, had adjacent protein-coding genes whose expressions were also significantly dysregulated (≥2.0-fold, p < 0.05). Majority of these pairs of lncRNAs and adjacent genes shared the same direction of dysregulation. For the selected adjacent gene-lncRNA pairs, significant Gene Ontology terms were embryonic appendage morphogenesis and neuron differentiation. This was the first study to comprehensively identify dysregulated lncRNAs in two different models of chronic epilepsy and will likely provide a novel insight into developing lncRNA therapeutics.
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Epilepsia/genética , RNA Longo não Codificante/genética , Animais , Modelos Animais de Doenças , Epilepsia/induzido quimicamente , Camundongos , Pilocarpina/farmacologiaRESUMO
The use of lamotrigine (LTG) can be limited by the occurrence of cutaneous adverse drug reactions (cADRs) that range from maculopapular eruption (MPE) to the more severe Stevens-Johnson syndrome and toxic epidermal necrolysis. A few human leukocyte antigen (HLA)-related genetic risk factors for carbamazepine-induced cADR have been identified. However, the HLA-related genetic risk factors associated with LTG-induced cADR are not yet well known. We performed HLA genotyping in 50 Korean patients with epilepsy, including 21 patients presenting LTG-induced MPE and 29 LTG-tolerant patients. A significant association between the HLA-A*2402 allele and LTG-induced MPE was identified, in comparison with the LTG-tolerant group (odds ratio [OR] 4.09, p = 0.025) and the general Korean population (OR 3.949, p = 0.005). The frequencies of the Cw*0102 or Cw*0702 alleles were significantly higher in the LTG-MPE group than in the Korean population, whereas the frequency of the A*3303 allele was lower. The coexistence of the A*2402 and Cw*0102 alleles was significantly associated with the LTG-MPE group when compared to the LTG-tolerant group (OR 7.88, p = 0.007). In addition, the Cw*0701 allele was more frequent in the LTG-tolerant group than in the Korean population. These findings suggest the presence of HLA-related genetic risk factors for LTG-induced MPE in the Korean population.
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Anticonvulsivantes/efeitos adversos , Toxidermias/etiologia , Toxidermias/genética , Antígeno HLA-A24/genética , Triazinas/efeitos adversos , Adolescente , Adulto , Idoso , Epilepsia/tratamento farmacológico , Feminino , Frequência do Gene , Genótipo , Humanos , Lamotrigina , Masculino , Pessoa de Meia-Idade , República da Coreia , Adulto JovemRESUMO
Depression is a frequent comorbidity in patients with epilepsy (PWE). However, it is often undertreated because of concerns of seizure exacerbation by antidepressant treatment. The effect of tianeptine on seizure frequency is not known as yet. Thus, we aimed to evaluate the influence of tianeptine on the seizure frequency in PWE. We retrospectively reviewed the medical records of PWE who received tianeptine between January 2006 and June 2013 at the Epilepsy Center of Seoul National University Hospital. Patients were excluded if the dose or type of antiepileptic drugs (AEDs) they took was altered at the start of tianeptine treatment or if the treatment period of tianeptine was <3 months. A total of 74 PWE were enrolled in our study (male: 32, mean age: 41.9±14.5). Sixty-nine patients had localization-related epilepsy, and 5 had idiopathic generalized epilepsy (IGE). Mean seizure frequency during the 3-month period just after tianeptine exposure was compared with the baseline seizure frequency, which showed no change in 69 (93.2%) patients, decrease in 2 (2.7%) patients, and increase in 3 patients (4.1%). The type of epileptic syndrome, the baseline seizure frequency, and the number of coadministered AEDs did not influence the change in seizure frequency after tianeptine prescription. Change in seizure frequency did not differ between the patients given tianeptine as an additive antidepressant and those given tianeptine as a replacement antidepressant. Our data suggest that tianeptine can be prescribed safely to PWE with depression without increasing the seizure frequency regardless of the baseline severity of epilepsy. Tianeptine may be actively considered as a first-choice antidepressant or as an alternative antidepressant in PWE with depression.
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Antidepressivos Tricíclicos/efeitos adversos , Transtorno Depressivo/tratamento farmacológico , Epilepsia/complicações , Tiazepinas/efeitos adversos , Adulto , Anticonvulsivantes/uso terapêutico , Antidepressivos Tricíclicos/uso terapêutico , Transtorno Depressivo/complicações , Epilepsia/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tiazepinas/uso terapêutico , Resultado do TratamentoRESUMO
Cardiovascular disease is a major public health issue, and smart diagnostic approaches play an important role in the analysis of electrocardiograms. Here, we present three-dimensional, soft electrodes of liquid metals that can be conformably attached to the surfaces of the heart and skin for long-term cardiac analysis. The fine micropillar structures of biocompatible liquid metals enable precise targeting to small tissue areas, allowing for spatiotemporal mapping and modulation of cardiac electrical activity with high resolution. The low mechanical modulus of these liquid-metal electrodes not only helps avoid inflammatory responses triggered by modulus mismatch between the tissue and electrodes, but also minimizes pain when embedded in biological tissues such as the skin and heart. Furthermore, in vivo experiments with animal models and human trials demonstrate long-term and accurate monitoring of electrocardiograms over a period of 30 days.
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Eletrodos , Animais , Humanos , Eletrocardiografia , Metais/química , Tecnologia sem Fio , Coração , RatosRESUMO
The bioinspired camera, comprising a single lens and a curved image sensor-a photodiode array on a curved surface-, was born of flexible electronics. Its economical build lends itself well to space-constrained machine vision applications. The curved sensor, much akin to the retina, helps image focusing, but the curvature also creates a problem of image distortion, which can undermine machine vision tasks such as object recognition. Here we report an anti-distortion single-lens camera, where 4096 silicon photodiodes arrayed on a curved surface in a nonuniform pattern assimilated to the distorting optics are the key to anti-distortion engineering. That is, the photo-pixel distribution pattern itself is warped in the same manner as images are warped, which correctively reverses distortion. Acquired images feature no appreciable distortion across a 120° horizontal view, as confirmed by their neural-network recognition accuracies. This distortion correction via photo-pixel array reconfiguration is a form of in-sensor computing.
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Integrating tactile feedback through haptic interfaces enhances experiences in virtual and augmented reality. However, electrotactile systems, which stimulate mechanoreceptors directly, often yield inconsistent tactile results due to variations in pressure between the device and the finger. In this study, we present the integration of a transparent electrotactile screen with pressure-sensitive transistors, ensuring highly consistent quantitative haptic sensations. These transistors effectively calibrate tactile variations caused by touch pressure. Additionally, we explore remote-distance tactile stimulations achieved through the interference of electromagnetic waves. We validated tactile perception using somatosensory evoked potentials, monitoring the somatosensory cortex response. Our haptic screen can stimulate diverse electrotactile sensations and demonstrate various tactile patterns, including Morse code and Braille, when integrated with portable smart devices, delivering a more immersive experience. Furthermore, interference of electric fields allows haptic stimulation to facilitate diverse stimulus positioning at lower current densities, extending the reach beyond direct contact with electrodes of our screen.
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Potenciais Somatossensoriais Evocados , Percepção do Tato , Tato , Transistores Eletrônicos , Humanos , Potenciais Somatossensoriais Evocados/fisiologia , Masculino , Percepção do Tato/fisiologia , Tato/fisiologia , Feminino , Adulto , Córtex Somatossensorial/fisiologia , Pressão , Dedos/fisiologia , Adulto Jovem , Mecanorreceptores/fisiologia , Retroalimentação Sensorial/fisiologiaRESUMO
We demonstrate a novel optical sensor for use in explosive gas detection, having a simple structure, ultrahigh sensitivity, room-temperature sensing/refreshing operation, and no local power requirements. The sensor relies on a fiber Fabry-Pérot interferometer prepared using poly(4-vinylpyridine), which induces cavity expansion upon absorption of nitrobenzene, thereby shifting the phase matching conditions of the resonating modes. An estimated sensitivity limit as low as 5 ppb was achieved.
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Tecnologia de Fibra Óptica/instrumentação , Gases/análise , Interferometria/instrumentação , Sistemas Microeletromecânicos/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de EquipamentoRESUMO
Organic nonvolatile resistive switching memory is developed via selective incorporation of fullerene derivatives, [6,6]-phenyl-C61 butyric acid methyl ester (PCBM), into the nanostructure of self-assembled poly(styrene-b-methyl methacrylate) (PS10 -b-PMMA130) diblock copolymer. PS10 -b-PMMA130 diblock copolymer provides a spatially ordered nanotemplate with a 10-nm PS nanosphere domain surrounded by a PMMA matrix. Spin casting of the blend solution of PS10 -b-PMMA130 and PCBM spontaneously forms smooth films without PCBM aggregation in which PCBM molecules are incorporated within a PS nanosphere domain of PS10 -b-PMMA130 nanostructure by preferential intermixing propensity of PCBM and PS. Based on the well-defined PS10-b-PMMA 130/PCBM nanostructure, resistive random access memory (ReRAM) exhibits significantly improved bipolar-switching behavior with stable and reproducible properties at low operating voltages (RESET at 1.3 V and SET at -1.5 V) under ambient conditions. Finally, flexible memory devices are achieved using a nanostructured PS10 -b-PMMA130 /PCBM composite in which no significant degradation of electrical properties is observed before and after bending.