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1.
Opt Express ; 29(20): 31364-31375, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615230

RESUMO

For the efficient radiative cooling of objects, coolers should emit heat within atmospheric transparent window and block heat absorption from the surrounding environments. Thus, selective emitters enable highly efficient cooling via engineered photonic structures such as metamaterials and multi-stacking structures. However, these structures require sophisticated fabrication processes and large quantities of materials, which can restrict mass-production. This study introduces an ultra-thin (∼1 µm) and near-unity selective emitter (UNSE) within the atmospheric window, which can be fabricated using simple and affordable process. The combination of infrared (IR) lossy layers and high index lossless layer enhances the resonance in the structure thus, the emissivity in long wavelength IR region increases to near-unity within a thickness of ∼1 µm.

2.
PLoS Biol ; 16(12): e2006660, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30543635

RESUMO

Interactions between membrane proteins are poorly understood despite their importance in cell signaling and drug development. Here, we present a co-immunoimmobilization assay (Co-II) enabling the direct observation of membrane protein interactions in single living cells that overcomes the limitations of currently prevalent proximity-based indirect methods. Using Co-II, we investigated the transient homodimerizations of epidermal growth factor receptor (EGFR) and beta-2 adrenergic receptor (ß2-AR) in living cells, revealing the differential regulation of these receptors' dimerizations by molecular conformations and microenvironment in a plasma membrane. Co-II should provide a simple, rapid, and robust platform for visualizing both weak and strong protein interactions in the plasma membrane of living cells.


Assuntos
Imunoprecipitação/métodos , Mapeamento de Interação de Proteínas/métodos , Análise de Célula Única/métodos , Linhagem Celular , Membrana Celular/metabolismo , Receptores ErbB/fisiologia , Humanos , Proteínas de Membrana/fisiologia , Ligação Proteica/fisiologia , Receptores Adrenérgicos beta 2/fisiologia , Transdução de Sinais
3.
IEEE Sens J ; 21(12): 13858-13869, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35790090

RESUMO

In this work, we propose a risk-aware physical distancing system to assure a private safety distance from others for reducing the chance of being affected by the COVID-19 or such kind of pandemic. In particular, we have formulated a physical distancing problem by capturing Conditional Value-at-Risk (CVaR) of a Bluetooth-enabled personal area network (PAN). To solve the formulated risk-aware physical distancing problem, we propose two stages solution approach by imposing control flow, linear model, and curve-fitting schemes. Notably, in the first stage, we determine a PAN creator's safe movement distance by proposing a probabilistic linear model. This scheme can effectively cope with a tail-risk from the probability distribution by satisfying the CVaR constraint for estimating safe movement distance. In the second stage, we design a Levenberg-Marquardt (LM)-based curve fitting algorithm upon the recommended safety distance and current distances between the PAN creator and others to find an optimal high-risk trajectory plan for the PAN creator. Finally, we have performed an extensive performance analysis using state-of-the-art Bluetooth data to establish the proposed risk-aware physical distancing system's effectiveness. Our experimental results show that the proposed solution approach can effectively reduce the risk of recommending safety distance towards ensuring private safety. In particular, for a 95% CVaR confidence, we can successfully deal with 45.11% of the risk for measuring the PAN creator's safe movement distance.

4.
Biomacromolecules ; 20(11): 4150-4157, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31545593

RESUMO

Polysaccharide-nanoparticle (NP) hybrid nanoclusters have great potential to revitalize diverse bioapplications; however, fabricating polysaccharide-based hybrid nanoclusters composed of high-quality NPs generated in the organic phase remains a challenge. Here, using calcium alginate as a polysaccharide/tetramethylammonium hydroxide (TMAOH) combination, we report a novel approach to the design of alginate-hydrophobic magnetic-plasmonic core-shell (MPCS) NP hybrid nanoclusters (A-MPCS HNCs). Furthermore, we observe the dependence of the formation of A-MPCS HNCs on the TMAOH concentration. The enhanced performance in both magnetic resonance r2 relaxivity and photoacoustic (PA) signals and the biocompatibility/bioactivity as well as the in vivo performance of A-MPCS HNCs shows them to be a promising magnetic resonance/photoacoustic dual-mode imaging agent. Our strategy could open doors to the use of other precious high-quality nanomaterials created in the organic phase via well-established synthetic chemistry in the design of alginate-hydrophobic nanomaterial hybrid nanoclusters, giving rise to novel and multifarious bioapplications.


Assuntos
Materiais Biocompatíveis/química , Nanopartículas/química , Nanoestruturas/química , Polissacarídeos/farmacologia , Alginatos/química , Alginatos/farmacologia , Ouro/química , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Técnicas Fotoacústicas , Polissacarídeos/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia
5.
Dermatol Ther ; 31(5): e12695, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30156014

RESUMO

Lichen planus of the lip (LPL) is not common, and only a few cases have been reported. Medical treatment modalities for LPL are not always effective. Therefore, treatment of this presentation is difficult and challenging. A 41-year-old man was referred to the dermatology clinic with a chronic, painful erosion on the lower lip and buccal mucosa. Treatment with topical steroids, systemic cyclosporine, dapsone, and systemic steroids failed. We performed surgical excision and mucosal advancement flap treatment, with complete response noted after 6 months. Surgical excision with mucosal advancement flap treatment may be effective for the treatment of refractory LPL.


Assuntos
Líquen Plano/cirurgia , Doenças Labiais/cirurgia , Mucosa Bucal/cirurgia , Retalhos Cirúrgicos , Adulto , Doença Crônica , Humanos , Líquen Plano/tratamento farmacológico , Líquen Plano/patologia , Masculino , Retratamento
6.
Sensors (Basel) ; 18(6)2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29914117

RESUMO

A glucose biosensor was utilized as a platform for the time-temperature integrator (TTI), a device for intelligent food packaging. The TTI system is composed of glucose oxidase, glucose, a pH indicator, and a three-electrode potentiostat, which produces an electrical signal as well as color development. The reaction kinetics of these response variables were analyzed under isothermal conditions. The reaction rates of the electrical current and color changes were 0.0360 ± 0.0020 (95% confidence limit), 0.0566 ± 0.0026, 0.0716 ± 0.0024, 0.1073 ± 0.0028 µA/min, and 0.0187 ± 0.0005, 0.0293 ± 0.0018, 0.0363 ± 0.0012, 0.0540 ± 0.0019 1/min, at 5, 15, 25, and 35 °C, respectively. The Arrhenius activation energy of the current reaction (Eacurrent) was 25.0 ± 1.6 kJ/mol and the Eacolor of the color reactions was 24.2 ± 0.6 kJ/mol. The similarity of these Ea shows agreement in the prediction of food qualities between the electrical signal and color development. Consequently, the function of the new time-temperature integrator system could be extended to that of a biosensor compatible with any electrical utilization equipment.


Assuntos
Técnicas Biossensoriais/métodos , Embalagem de Alimentos/métodos , Glucose/análise , Temperatura , Técnicas Biossensoriais/instrumentação , Eletrodos , Alimentos/normas , Embalagem de Alimentos/instrumentação , Glucose/metabolismo , Glucose Oxidase/metabolismo , Concentração de Íons de Hidrogênio , Fatores de Tempo
7.
Angew Chem Int Ed Engl ; 54(24): 7028-32, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-25940988

RESUMO

We present a single-molecule diffusional-mobility-shift assay (smDIMSA) for analyzing the interactions between membrane and water-soluble proteins in the crowded membrane of living cells. We found that ligand-receptor interactions decreased the diffusional mobility of ErbB receptors and ß-adrenergic receptors, as determined by single-particle tracking with super-resolution microscopy. The shift in diffusional mobility was sensitive to the size of the water-soluble binders that ranged from a few tens of kilodaltons to several hundred kilodaltons. This technique was used to quantitatively analyze the dissociation constant and the cooperativity of antibody interactions with the epidermal growth factor receptor and its mutants. smDIMSA enables the quantitative investigation of previously undetected ligand-receptor interactions in the intact membrane of living cells on the basis of the diffusivity of single-molecule membrane proteins without ligand labeling.


Assuntos
Receptores ErbB/metabolismo , Ligantes , Animais , Anticorpos Monoclonais/imunologia , Células COS , Membrana Celular/metabolismo , Cetuximab/imunologia , Chlorocebus aethiops , Difusão , Receptores ErbB/química , Receptores ErbB/genética , Microscopia , Mutação
8.
Proteomics ; 14(12): 1494-502, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24729417

RESUMO

High-grade gliomas are one of the most common brain tumors and notorious for poor prognosis due to their malignant nature. Gliomas have an extensive area of hypoxia, which is critical for glioma progression by inducing aggressiveness and activating the angiogenesis process in the tumor microenvironment. To resolve the factors responsible for the highly malignant nature of gliomas, we comprehensively profiled the U373MG glioma cell secretome-exosome and soluble fraction under hypoxic and normoxic conditions. A total of 239 proteins were identified from the exosome and soluble fractions. Vascular endothelial growth factor, stanniocalcin 1 (STC1) and stanniocalcin 2, and insulin-like growth factor binding protein 3 and 6, enriched in the soluble fraction, and lysyl oxidase homolog 2 enriched in the exosomal fraction were identified as upregulated proteins by hypoxia based on a label-free quantitative analysis. STCs and insulin-like growth factor binding proteins, which were identified as secretory proteins under hypoxic conditions, were highly correlated with glioma grade in human patients by microarray analysis. An in vitro scratch wound assay revealed that STC1 and 2 have important functions in the induction of cell migration in a hypoxia-dependent manner, suggesting that they are hypoxia-dependent migration factors.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Movimento Celular , Glioma/metabolismo , Hipóxia/fisiopatologia , Proteoma/análise , Biomarcadores Tumorais/genética , Western Blotting , Neoplasias Encefálicas/patologia , Proliferação de Células , Cromatografia Líquida/métodos , Exossomos/metabolismo , Glioma/patologia , Glicoproteínas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Gradação de Tumores , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas em Tandem/métodos , Células Tumorais Cultivadas , Microambiente Tumoral
9.
J Endod ; 50(3): 310-315, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38141831

RESUMO

INTRODUCTION: This study investigated endodontically treated teeth that were replaced by dental implants at the University of North Carolina (UNC) at Chapel Hill School of Dentistry. The primary objective of this study was to determine the reasons leading to the extraction of endodontically treated teeth and their subsequent replacement with dental implants. The secondary objective was to evaluate the proportion of these teeth that, according to experienced endodontists, could have been preserved. METHODS: The UNC-Chapel Hill's dental electronic health records between 2004 and 2019 were probed for implant placement that replaced root canal-treated teeth. Preextraction radiographs and clinical charts were examined to ascertain the primary reason related to the extraction and to compile a profile for each case. In cases in which endodontic failure was the primary reason for extraction, radiographs and clinical findings were evaluated by 2experienced endodontists to assess potential treatment options. RESULTS: Between 2004 and 2019, 29.3% (1564 of 5229) of teeth replaced by dental implants at UNC School of Dentistry had undergone root canal treatment, with the mandibular first molar being the most commonly replaced tooth. The leading reasons for extraction were recurrent caries associated with defective restoration (26.6%), fracture of coronal structure (21.5%), vertical root fracture (20.9%), compromised periodontal condition (13.8%), and endodontic failure (2.4%). Two experienced endodontists evaluated extractions due to endodontic failure and concluded that 61.7% of them could have been candidates for endodontic retreatment. CONCLUSION: Substantial loss of tooth structure was the leading cause of extraction of root canal-treated teeth, followed by vertical root fracture and periodontal disease. Although endodontic failure constituted a minor portion of the reasons for extraction, a considerable number of teeth were extracted due to vertical root fractures following root canal treatment. A significant proportion of the extracted teeth due to endodontic failure could have been considered as potential candidates for endodontic retreatment.


Assuntos
Cárie Dentária , Implantes Dentários , Doenças Periodontais , Dente não Vital , Humanos , Dente não Vital/diagnóstico por imagem , Estudos Retrospectivos , Tratamento do Canal Radicular/efeitos adversos
10.
ACS Appl Mater Interfaces ; 16(1): 643-654, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38147638

RESUMO

Among the various existing layered compounds, silicon diselenide (SiSe2) possesses diverse chemical and physical properties, owing to its large interlayer spacing and interesting atomic arrangements. Despite the unique properties of layered SiSe2, it has not yet been used in energy applications. Herein, we introduce the synthesis of layered SiSe2 through a facile solid-state synthetic route and demonstrate its versatility as a sulfide solid electrolyte (SE) additive for all-solid-state batteries (ASSBs) and as an anode material for Li-ion batteries (LIBs). Li-argyrodites with various compositions substituted with SiSe2 are synthesized and evaluated as sulfide SEs for ASSBs. SiSe2-substituted Li-argyrodites exhibit high ionic conductivities, low activation energies, and high air stabilities. In addition, when using a sulfide SE, the ASSB full cell exhibits a high discharge/charge capacity of 202/169 mAh g-1 with a high initial Coulombic efficiency (ICE) of 83.7% and stable capacity retention at 1C after 100 cycles. Furthermore, the Li-storage properties of SiSe2 as an anode material for LIBs are evaluated, and its Li-pathway mechanism is explored by using various cutting-edge ex situ analytical tools. Moreover, the SiSe2 nanocomposite anode exhibits a high Li- insertion/extraction capacity of 950/775 mAh g-1, a high ICE of 81.6%, a fast rate capability, and stable capacity retention after 300 cycles. Accordingly, layered SiSe2 and its versatile applications as a sulfide SE additive for ASSBs and an anode material for LIBs are promising candidates in energy storage applications as well as myriad other applications.

11.
Biosens Bioelectron ; 249: 116007, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38194812

RESUMO

Chitosan (CS)-stabilized platinum nanoparticles (CS/PtNPs) were employed to develop a novel aptamer-based dual-mode colorimetric and photothermal biosensor for selective detection of kanamycin (KAN). As a peroxidase-like catalyst, the CS/PtNPs showed outstanding catalytic activity for the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide (H2O2). As a stabilizing agent, CS excelled at fixing the KAN binding aptamer on the surface of the CS/PtNPs, amplifying their catalytic activity and enhancing colloidal dispersion and stability. The oxidized TMB (TMBox) functioned as a signal for the colorimetric, photothermal aptasensor because of its observable absorbance of light in the visible and near-infrared (NIR) regions. When light from a NIR laser was absorbed by the TMBox in the reaction solution, heat was generated in inverse proportion to the KAN concentration. The developed colorimetric and photothermal modes of the aptasensor showed a linear detection range of 0.1-50 and 0.5-50 µM, with a limit of detection (LOD) of 0.04 and 0.41 µM, respectively. Moreover, the aptasensor successfully determined KAN concentrations in spiked milk samples, verifying the reliability and reproducibility in practical applications. The dual-mode aptasensor based on CS/PtNPs for KAN detection, utilizing both color change and heat generation signals through a single probe (TMBox), demonstrates rapid response, simplicity in operation, cost-effectiveness, and high sensitivity. In addition, unlike typical immunoassays, this aptamer-based peroxidase-like nanozyme activation and inhibition strategy required no washing process, which was very effective in terms of reducing the time required for an assay and sustaining a high sensitivity.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Canamicina , Platina , Reprodutibilidade dos Testes , Colorimetria , Peróxido de Hidrogênio , Peroxidase , Aptâmeros de Nucleotídeos/metabolismo
12.
Food Sci Biotechnol ; 33(7): 1707-1714, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623436

RESUMO

Attempts to improve low absorption and rapid metabolic conversion of curcumin were made by developing curcumin-loaded bilayer nanoliposomes coated with chitosan and alginate for intestinal-specific drug delivery. A curcumin-loaded nano-liposome was prepared with optimized formulations with phosphatidylcholine, curcumin, chitosan, and alginate. The particle size of the optimized formulation was approximately 400 nm, and the encapsulation efficiency was more than 99%. In the in vitro release study, curcumin release from the curcumin-loaded nanoliposome with double layers of chitosan/alginate (CNL-CH/AL) was suppressed in the simulated gastric fluid (SGF, pH 1.2) and enhanced in the simulated intestinal fluid (SIF, pH 6.8). In the in vivo pharmacokinetic study in rats, the CNL-CH/AL-treated group showed a prolonged absorption pattern of curcumin and the area under the plasma concentration-time curve from 0 to 24 h (AUC0-24) was improved 109-fold compared to the control group treated with a curcumin solution without a nanocarrier.

13.
J Photochem Photobiol B ; 250: 112831, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38134574

RESUMO

Cancer is a life-threatening disease when it is diagnosed at a late stage or treatment procedures fail. Inhibiting cancer cells in the tumor environment is a significant challenge for anticancer therapy. The photothermal effects of nanomaterials are being studied as a new cancer treatment. In this work, rhenium disulfide (ReS2) nanosheets were made by liquid exfoliation with gum arabic (GA) and coated with silver nanoparticles (AgNPs) to produce reactive oxygen species that destroy cancer cells. The synthesized AgNP-GA-ReS2 NPs were characterized using UV, DLS, SEM, TEM, and photothermal studies. According to the DLS findings, the NPs were about 216 nm in size and had a zeta potential of 76 mV. The TEM and SEM analyses revealed that the GA-ReS2 formed single-layered nanosheets on which the AgNPs were distributed. The photothermal effects of the AgNP-GA-ReS2 NPs at 50 µg/mL were tested with an 808 nm laser at 1.2 W cm-2, and they reached 55.8 °C after 5 min of laser irradiation. MBA-MB-231 cells were used to test the cytotoxicity of the newly designed AgNP-GA-ReS2 NPs with and without laser irradiation for 5 min. At 50 µg/mL, the AgNP-GA-ReS2 showed cytotoxicity, which was confirmed with calcein and EtBr staining. The DCFH-DA and flow cytometry analyses demonstrated that AgNP-GA-ReS2 nanosheets under NIR irradiation generated ROS with high anticancer activity, in addition to the photothermal effects.


Assuntos
Nanopartículas Metálicas , Neoplasias , Rênio , Humanos , Nanopartículas Metálicas/toxicidade , Prata/farmacologia
14.
iScience ; 26(1): 105780, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36590160

RESUMO

The increasing advances in thermal radiation regulators have attracted growing interest, particularly in infrared sources, thermal management, and camouflage. Despite many advances in dynamic thermal emitters with great controllability, sustained external energy is required to maintain the desired emission. In this study, we present a polarization-driven thermal emission regulator based on a two-way control: i) phase change and ii) polarization tuning. Based on a conventional, non-volatile phase change material, i.e., Ge2Sb2Te5 (GST), we newly introduce an anisotropic medium for facile emissivity regulation without heat energy consumption. A rigorous coupled-wave analysis method provides design guidelines for finding optimal structural parameters. We utilized a simple glancing angle deposition process which induces tilted self-aligned nanocolumns with anisotropic properties. The fabricated sample shows polarization-sensitive thermal regulation through thermal imaging spectroscopic measurement. Additionally, we manufactured a multispectral visibly/thermally camouflaged patch that identifies encrypted information at a specific polarization state for a proof-of-concept demonstration.

15.
Environ Sci Pollut Res Int ; 30(16): 48157-48167, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36750517

RESUMO

Ex situ mineralization of CO2 is a promising technology that employs Ca- and Mg-rich industrial wastes but it simultaneously produces end products. Although Mg is a major mineralization source, it can adversely impact carbonate precipitation and crystal stability during co-precipitation in combination with Ca2+. In this study, the effects of Mg2+ ions on the mineralization process and its products were investigated using precipitates formed at different aqueous concentrations of Mg2+. The final phases of the precipitates were quantitatively evaluated at the end of each process. The alterations undergone by the calcite crystals, which constituted the dominant carbonate phase in each experiment, were analyzed using a sophisticated crystallographic approach. Aragonite was detected at high Mg2+ concentrations (Mg2+/Ca2+ ratio of 2.00), although brucite was the sole phase of the Mg crystal. The increase in Mg2+ ion concentration induced the formation of an amorphous solid. The results revealed that a drastic transformation of the calcite lattice occurred when the ratio of Mg2+/Ca2+ exceeded 1.00, agreeing with the shifts observed in the calcite structure upon comparing the precipitates formed at the Mg2+/Ca2+ ratios of 1.00 and 2.00, wherein microstrain and crystallite sizes changed from 0.040 and 55.33 nm to 0.1533 and 12.35 nm, respectively. At a Mg2+/Ca2+ ratio of 2.00, 6.51% of the Ca2+ ions in the calcite structure were substituted by Mg2+, increasing the surface energy of the crystal and the solubility of the carbonate. Therefore, Mg2+ is a potential hindrance that can impede the precipitation of carbonates and increase instability at certain concentrations.


Assuntos
Carbono , Magnésio , Magnésio/química , Carbonato de Cálcio/química , Carbonatos , Água/química
16.
Int J Biol Macromol ; 244: 124982, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37244326

RESUMO

Transition metal dichalcogenides (TMDs) have gained considerable attention for a broad range of applications, including cancer therapy. Production of TMD nanosheets using liquid exfoliation provides an inexpensive and facile route to achieve high yields. In this study, we developed TMD nanosheets using gum arabic as an exfoliating and stabilizing agent. Different types of TMDs, including MoS2, WS2, MoSe2, and WSe2 nanosheets, were produced using gum arabic and were characterized physicochemically. The developed gum arabic TMD nanosheets exhibited a remarkable photothermal absorption capacity in the near-infrared (NIR) region (808 nm and 1 W⋅cm-2). The drug doxorubicin was loaded on the gum arabic-MoSe2 nanosheets (Dox-G-MoSe2), and the anticancer activity was evaluated using MDA-MB-231 cells and a water-soluble tetrazolium salt (WST-1) assay, live and dead cell assays, and flow cytometry. Dox-G-MoSe2 significantly inhibited MDA-MB-231 cancer cell proliferation under the illumination of an NIR laser at 808 nm. These results indicate that Dox-G-MoSe2 is a potentially valuable biomaterial for breast cancer therapy.


Assuntos
Neoplasias da Mama , Compostos Organosselênicos , Humanos , Feminino , Goma Arábica , Molibdênio/química , Morfolinas , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/farmacologia , Doxorrubicina/química
17.
Sci Adv ; 9(39): eadi8918, 2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37756405

RESUMO

Numerous wireless optogenetic systems have been reported for practical tether-free optogenetics in freely moving animals. However, most devices rely on battery-powered or coil-powered systems requiring periodic battery replacement or bulky, high-cost charging equipment with delicate antenna design. This leads to spatiotemporal constraints, such as limited experimental duration due to battery life or animals' restricted movement within specific areas to maintain wireless power transmission. In this study, we present a wireless, solar-powered, flexible optoelectronic device for neuromodulation of the complete freely behaving subject. This device provides chronic operation without battery replacement or other external settings including impedance matching technique and radio frequency generators. Our device uses high-efficiency, thin InGaP/GaAs tandem flexible photovoltaics to harvest energy from various light sources, which powers Bluetooth system to facilitate long-term, on-demand use. Observation of sustained locomotion behaviors for a month in mice via secondary motor cortex area stimulation demonstrates the notable capabilities of our device, highlighting its potential for space-free neuromodulating applications.


Assuntos
Optogenética , Tecnologia sem Fio , Camundongos , Animais , Optogenética/métodos , Movimento , Fontes de Energia Elétrica
18.
Sci Adv ; 9(5): eadf5883, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36724224

RESUMO

Recent advances in passive radiative cooling systems describe a variety of strategies to enhance cooling efficiency, while the integration of such technology with a bioinspired design using biodegradable materials can offer a research opportunity to generate energy in a sustainable manner, favorable for the temperature/climate system of the planet. Here, we introduce stretchable and ecoresorbable radiative cooling/heating systems engineered with zebra stripe-like patterns that enable the generation of a large in-plane temperature gradient for thermoelectric generation. A comprehensive study of materials with theoretical evaluations validates the ability to accomplish the target performances even under external mechanical strains, while all systems eventually disappear under physiological conditions. Use of the zebra print for selective radiative heating demonstrates an unexpected level of temperature difference compared to use of radiative cooling emitters alone, which enables producing energy through resorbable silicon-based thermoelectric devices. The overall result suggests the potential of scalable, ecofriendly renewable energy systems.

19.
Polymers (Basel) ; 14(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36145966

RESUMO

Dielectric elastomer actuators (DEAs), a type of electroactive polymers (EAPs), are smart materials that are used in various fields such as artificial muscles and biomimetic robots. In this study, graphene nanoplatelets (GNPs), which are conductive carbon fillers, were added to a widely used DEA, namely, polydimethylsiloxane (PDMS), to improve its low actuated strain. Four grades of GNPs were used: H5, H25, M5, and M25 (here, the number following the letter indicates the average particle size of the GNPs in µm). The average layer thickness of the H grade is 13−14 nm and that of the M grade is 5−7 nm. PDMS composites were prepared by adding 0.5, 1, 2, and 3 wt% of each GNP, following which the mechanical properties, dielectric properties, and actuated strain of the composites were measured. The mechanical properties were found to increase as the particle size increased. Regarding the dielectric characteristics, it was found that the higher the aspect ratio of the filler, the easier the formation of a micro-capacitor network in the composite­this led to an increase in the dielectric constant. In addition, the higher amounts of GNPs in the composites also led to an increase in the dielectric constant. For the actuated strain analysis, the electromechanical sensitivity was calculated using the ratio of the dielectric constant to the Young's modulus, which is proportional to the strain. However, it was found that when the loss tangent was high, the performance of the actuated strain decreased owing to the conversion of electric energy into thermal energy and leakage current loss. As a result, the highest actuated strain was exhibited by the M25 composite, with an actuated strain value of 3.01% measured at a low electric field (<4 kV/mm). In conclusion, we proved that the GNP−PDMS composites with a thin layer and large particle size exhibited high deformation.

20.
J Inflamm Res ; 15: 2665-2693, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35509323

RESUMO

Incense burning is practiced alongside many sacred rituals across different regions of the world. Invariable constituents of incense brands are 21% (by weight) herbal and wood powder, 33% bamboo stick, 35% fragrance material, and 11% adhesive powder. Major incense-combustion outputs include particulate matter (PM), volatile organic content, and polyaromatic hydrocarbons. The relative toxicity of these products is an implicit function of particle size and incomplete combustion, which in turn vary for a specific incense brand. Lately, the attention given to the Air Quality Index by international regulatory bodies has created concern about mounting PM toxicity. The uncharacteristically small physical dimensions of these entities complicates their detection, and with no effect of gravity PM fractions rapidly contribute to oxidative stress, enhancing random biochemical reactions upon being inhaled. Incense burning generates four times the PM extent (45 mg•g-1) of cigarettes (~10 mg•g-1). Several poisonous gases, such as CO, CO2, NO2, and SO2, and the unavoidable challenge of disposing of the burnt incense ash further add to the toxicity. Taken together, these issues demonstrate that incense burning warrants prompt attention. The aim of this article is to highlight the toxicity of incense-combustion materials on the environment and human health. This discussion could be significant in framing future policy regarding ecofriendly incense manufacture and reduced usage.

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