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1.
Nanotechnology ; 33(24)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35255485

RESUMO

Since uncontrolled lithium (Li) dendrite growth and dendrite-induced dead Li severely limit the development of Li metal batteries, 3D Cu current collectors can effectively alleviate these problems during Li plating/stripping. Herein, one-step galvanostatic electrodeposition method is employed to fabricate a new current collector on Cu foam decorated with large-scale and uniform 3D porous Cu-based nanoflake (NF) structures (abbreviated as 3D Cu NF@Cu foam). This 3D structure with large internal surface areas not only generates lithophilic surface copper oxides and hydroxides as charge centers and nucleation sites for Li insertion/extraction, but also endows abundant space with interlinked NFs for buffering the cell volume expansion and increasing battery performance. As a result, Li-deposited 3D Cu NF@Cu foam current collector can realize stable cycling over 455 cycles with an average Coulombic efficiency of 98.8% at a current density of 1.0 mA cm-2, as well as a prolonged lifespan of >380 cycles in symmetrical cell without short-circuit, which are superior to those of blank Cu foam current collector. This work realizes Li metal anode stabilization by constructing 3D porous Cu NFs current collectors, which can advance the development of Li metal anode for battery industries.

2.
PLoS One ; 15(9): e0238775, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32886697

RESUMO

OBJECTIVE: Findings regarding the prognostic value of soluble suppression of tumorigenecity-2 (sST2) in patients with coronary artery disease (CAD) remain inconsistent. Therefore, we conducted this meta-analysis to investigate the long-term prognostic value of sST2 in patients with CAD. METHODS: A comprehensive literature search was conducted across the PubMed, Embase, and Cochrane Library databases up to June 3, 2020. The primary outcome was major adverse cardiac events (MACEs). The secondary outcomes were all-cause mortality, cardiovascular (CV) death, heart failure (HF), and myocardial infarction (MI). Pooled estimations and 95% confidence intervals (CIs) were assessed using a random-effects model. RESULTS: Twenty-two articles that enrolled a total of 17,432 patients with CAD were included in the final analysis. CAD patients in the highest categories of baseline sST2 had a significantly higher risk of MACEs (HR: 1.42, 95% CI: 1.09-1.76), all-cause mortality (HR: 2.00, 95% CI: 1.54-2.46), and CV death (HR: 1.42, 95% CI: 1.15-1.68), HF (HR: 2.41, 95% CI: 1.87-2.94), but not that of MI (HR: 1.15, 95% CI: -0.73-3.04), than those in the lowest categories. These results were consistent when baseline sST2 was presented as continuous values in one unit increments. Moreover, subgroup analysis showed that elevated baseline sST2 levels increased the long-term risk of MACEs in the acute coronary syndrome (ACS) population (HR: 1.74, 95% CI: 1.39-2.09) but only showed a trend toward higher risk of MACEs in the non-ACS population (HR: 1.09, 95% CI: 0.87-1.30). CONCLUSIONS: The findings suggest that a higher concentration of baseline sST2 is associated with a higher risk of MACEs, all-cause mortality, CV death, and HF in patients with CAD. Elevated sST2 levels could significantly predict future MACEs in the ACS population but not in the non-ACS population.


Assuntos
Doença da Artéria Coronariana/complicações , Insuficiência Cardíaca/complicações , Proteína 1 Semelhante a Receptor de Interleucina-1/sangue , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/mortalidade , Biomarcadores/sangue , Feminino , Insuficiência Cardíaca/mortalidade , Humanos , Interleucina-33/sangue , Masculino , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Prognóstico
3.
Sensors (Basel) ; 20(15)2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32707858

RESUMO

To meet the urgent market demand for small package size and high reliability performance for automotive CMOS image sensor (CIS) application, wafer level chip scale packaging (WLCSP) technology using through silicon vias (TSV) needs to be developed to replace current chip on board (COB) packages. In this paper, a WLCSP with the size of 5.82 mm × 5.22 mm and thickness of 850 µm was developed for the backside illumination (BSI) CIS chip using a 65 nm node with a size of 5.8 mm × 5.2 mm. The packaged product has 1392 × 976 pixels and a resolution of up to 60 frames per second with more than 120 dB dynamic range. The structure of the 3D package was designed and the key fabrication processes on a 12" inch wafer were investigated. More than 98% yield and excellent optical performance of the CIS package was achieved after process optimization. The final packages were qualified by AEC-Q100 Grade 2.

4.
Proc Natl Acad Sci U S A ; 116(43): 21427-21437, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31601737

RESUMO

Pharmacology and optogenetics are widely used in neuroscience research to study the central and peripheral nervous systems. While both approaches allow for sophisticated studies of neural circuitry, continued advances are, in part, hampered by technology limitations associated with requirements for physical tethers that connect external equipment to rigid probes inserted into delicate regions of the brain. The results can lead to tissue damage and alterations in behavioral tasks and natural movements, with additional difficulties in use for studies that involve social interactions and/or motions in complex 3-dimensional environments. These disadvantages are particularly pronounced in research that demands combined optogenetic and pharmacological functions in a single experiment. Here, we present a lightweight, wireless, battery-free injectable microsystem that combines soft microfluidic and microscale inorganic light-emitting diode probes for programmable pharmacology and optogenetics, designed to offer the features of drug refillability and adjustable flow rates, together with programmable control over the temporal profiles. The technology has potential for large-scale manufacturing and broad distribution to the neuroscience community, with capabilities in targeting specific neuronal populations in freely moving animals. In addition, the same platform can easily be adapted for a wide range of other types of passive or active electronic functions, including electrical stimulation.


Assuntos
Optogenética/métodos , Farmacologia/métodos , Animais , Encéfalo/metabolismo , Química Encefálica , Channelrhodopsins/metabolismo , Estimulação Elétrica , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Optogenética/instrumentação , Farmacologia/instrumentação , Próteses e Implantes , Tecnologia sem Fio/instrumentação
5.
Adv Mater ; 31(42): e1902739, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31489737

RESUMO

Transient forms of electronics, systems that disintegrate, dissolve, resorb, or sublime in a controlled manner after a well-defined operating lifetime, are of interest for applications in hardware secure technologies, temporary biomedical implants, "green" consumer devices and other areas that cannot be addressed with conventional approaches. Broad sets of materials now exist for a range of transient electronic components, including transistors, diodes, antennas, sensors, and even batteries. This work reports the first examples of transient light-emitting diodes (LEDs) that can completely dissolve in aqueous solutions to biologically and environmentally benign end products. Thin films of highly textured ZnO and polycrystalline Mo serve as semiconductors for light generation and conductors for transparent electrodes, respectively. The emitted light spans a range of visible wavelengths, where nanomembranes of monocrystalline silicon can serve as transient filters to yield red, green, and blue LEDs. Detailed characterization of the material chemistries and morphologies of the constituent layers, assessments of their performance properties, and studies of their dissolution processes define the underlying aspects. These results establish an electroluminescent light source technology for unique classes of optoelectronic systems that vanish into benign forms when exposed to aqueous conditions in the environment or in living organisms.


Assuntos
Semicondutores , Molibdênio/química , Fenômenos Ópticos , Solubilidade , Água/química , Óxido de Zinco/química
6.
Nat Biomed Eng ; 3(8): 644-654, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31391594

RESUMO

Capabilities in real-time monitoring of internal physiological processes could inform pharmacological drug-delivery schedules, surgical intervention procedures and the management of recovery and rehabilitation. Current methods rely on external imaging techniques or implantable sensors, without the ability to provide continuous information over clinically relevant timescales, and/or with requirements in surgical procedures with associated costs and risks. Here, we describe injectable classes of photonic devices, made entirely of materials that naturally resorb and undergo clearance from the body after a controlled operational lifetime, for the spectroscopic characterization of targeted tissues and biofluids. As an example application, we show that the devices can be used for the continuous monitoring of cerebral temperature, oxygenation and neural activity in freely moving mice. These types of devices should prove useful in fundamental studies of disease pathology, in neuroscience research, in surgical procedures and in monitoring of recovery from injury or illness.


Assuntos
Implantes Absorvíveis , Técnicas Biossensoriais/instrumentação , Óptica e Fotônica/instrumentação , Análise Espectral/métodos , Animais , Materiais Biocompatíveis , Engenharia Biomédica/instrumentação , Análise Química do Sangue/instrumentação , Análise Química do Sangue/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Desenho de Equipamento , Feminino , Camundongos , Modelos Animais , Neurociências , Fibras Ópticas , Silício/química , Temperatura
7.
ACS Appl Mater Interfaces ; 11(12): 11106-11111, 2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30855937

RESUMO

Until now, scalable fabrication and utilization of superamphiphobic surfaces based on sophisticated structures has remained challenging. Herein, we develop an applicable superamphiphobic surface with nano-Ni pyramid/micro-Cu cone structures prepared by cost-effective electrochemical deposition. More importantly, excellent dynamic wettability is achieved, exhibiting as ultralow sliding angle (∼0°), multiple droplets rebounding (13 times), and a total rejection. The supportive cushions trapped within the dual-scale micro/nanostructures is proved to be the key factor contributing to such high liquid repellency, whose existence is intuitively ascertained at both solid-air-liquid and water-solid-oil systems in this work. In addition, the enduring reliability of the wetting performance under various harsh conditions further endows the surface with broader application prospects.

8.
Sci Adv ; 5(1): eaav3294, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30746477

RESUMO

Wearable sweat sensors rely either on electronics for electrochemical detection or on colorimetry for visual readout. Non-ideal form factors represent disadvantages of the former, while semiquantitative operation and narrow scope of measurable biomarkers characterize the latter. Here, we introduce a battery-free, wireless electronic sensing platform inspired by biofuel cells that integrates chronometric microfluidic platforms with embedded colorimetric assays. The resulting sensors combine advantages of electronic and microfluidic functionality in a platform that is significantly lighter, cheaper, and smaller than alternatives. A demonstration device simultaneously monitors sweat rate/loss, pH, lactate, glucose, and chloride. Systematic studies of the electronics, microfluidics, and integration schemes establish the key design considerations and performance attributes. Two-day human trials that compare concentrations of glucose and lactate in sweat and blood suggest a potential basis for noninvasive, semi-quantitative tracking of physiological status.


Assuntos
Técnicas Biossensoriais/instrumentação , Colorimetria/métodos , Dispositivos Lab-On-A-Chip , Microfluídica/métodos , Pele/metabolismo , Suor/química , Dispositivos Eletrônicos Vestíveis , Fontes de Energia Bioelétrica , Cloretos/análise , Glucose/análise , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/análise , Masculino
9.
J Colloid Interface Sci ; 494: 178-184, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28157636

RESUMO

In this work, resistance switching behaviours in solution processed chromium (Cr)-doped strontium titanate (SrTiO3) films have been investigated. Undoped SrTiO3 film shows I-V characteristics of typical nonlinear resistor and no resistance hysteresis loops are observed. On the contrary, Cr-doped SrTiO3 films show stable and reversible hysteresis loops, which can be controlled by applying different voltage bias. Based on a series of characterization results, including X-ray diffraction (XRD), Raman and X-ray photoelectron spectroscopy (XPS), we infer that Ti4+ is substituted by Cr3+, giving rise to increased concentration of oxygen vacancies. Therefore, the observed resistance switching phenomenon is attributed to voltage driven oxygen vacancy migration. Furthermore, gradually decreased overall resistance is also realized under repeated sweeping cycles.

10.
Langmuir ; 32(14): 3385-92, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-27003754

RESUMO

Silver nanosheets with a nanogap smaller than 10 nm and high reproducibility were constructed through simple and environmentally friendly electrodeposition method on copper plate. The sizes of the nanogaps can be varied from around 7 to 150 nm by adjusting the deposition time and current density. The nanosheets with different nanogaps exhibited varied surface-enhanced Raman scattering (SERS) properties due to electromagnetic mechanism (EM). The optimized high density silver nanosheets with a nanogap smaller than 10 nm showed effective SERS ability with an enhanced factor as high as 2.0 × 10(5). Furthermore, the formation mechanism of the nanosheets during the electrodeposition process has been investigated by discussing the influence of boric acid and current density. This method has proved to be applicable on different metal substrates, which exhibits the potential to be widely used in different fields.

11.
Biomed Res Int ; 2015: 971683, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26457306

RESUMO

OBJECTIVE: To investigate the correlation of CTRP9 with coronary atherosclerosis. METHODS: Coronary angiography confirmed CAD in 241 patients (62 received CABG) and non-CAD in 121 (55 received valve replacement). RESULTS: Serum levels of LDL-C, CRP, TNF-α, IL-6, and leptin in CAD patients were significantly higher than those in non-CAD patients (P < 0.05), but APN and CTRP9 were lower (P < 0.05). Serum levels of CTRP9 and APN were negatively related to BMI, HOMA-IR, TNF-α, IL-6, and leptin but positively to HDL-C (P < 0.05) in CAD patients. After adjustment of APN, CTRP9 was still related to the above parameters. Serum CTRP9 was a protective factor of CAD (P < 0.05). When compared with non-CAD patients, leptin mRNA expression increased dramatically, while CTRP9 mRNA expression reduced markedly in epicardial adipose tissue of CAD patients (P < 0.05). The leptin expression and macrophage count in CAD group were significantly higher than in non-CAD group, but CAD patients had a markedly lower CTRP9 expression (P < 0.05). CONCLUSIONS: Circulating and coronary CTRP9 plays an important role in the inflammation and coronary atherosclerosis of CAD patients. Serum CTRP9 is an independent protective factor of CAD.


Assuntos
Adiponectina/genética , Doença da Artéria Coronariana/genética , Glicoproteínas/genética , Leptina/genética , Adiponectina/biossíntese , Adiponectina/sangue , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Idoso , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/patologia , Feminino , Regulação da Expressão Gênica , Estudos de Associação Genética , Glicoproteínas/biossíntese , Glicoproteínas/sangue , Humanos , Leptina/biossíntese , Leptina/sangue , Masculino , Pessoa de Meia-Idade , Pericárdio/metabolismo , Pericárdio/patologia , RNA Mensageiro/biossíntese , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral
12.
Langmuir ; 31(39): 10807-12, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26366852

RESUMO

Caterpillar-like hierarchical structured Cu/Ni-Co coatings were fabricated by a simple two-step method of combined electroless and electrodeposition. Both contact angles and sliding angles were measured to investigate the hydrophobicity after stearic acid modification. The results revealed the contact angle was as high as 165.5°(superhydrophobic), while the sliding angle was only 3.5°, which makes it very promising as self-cleaning material. Wetting transition from slippery hydrophobicity to sticky hydrophobicity happened upon heat treatment. The scanning electron microscopy (SEM) analysis disclosed the morphology change of the hierarchical structure during the heat treatment leading to the wetting state transition. Different models of wetting states were raised and calculated to provide further confirmation of the transition. The contact angle remained larger than 156° when the pH value ranged from 1 to 14 and the heat-treatment temperature was from 100 to 250 °C. Such hierarchical micronanostructure and its special hydrophobicity are expected to have practical application in industry.


Assuntos
Cobalto/química , Cobre/química , Temperatura Alta , Níquel/química , Molhabilidade , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Estrutura Molecular , Propriedades de Superfície
13.
Langmuir ; 31(39): 10850-8, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26391725

RESUMO

Inspired by the self-cleaning of cicada wings, well-aligned Au-coated Ni nanocone arrays (Au@Ni NAs) have been fabricated by a simple and cheap electrodeposition method. After surface modification of n-hexadecanethiol, self-cleaning can be realized on this long-lived superhydrophobic surface with extremely low adhesive force. Switchable adhesion is obtained on its complementary porous surface. The porous Au structure is fabricated by a geometric replica of the nanocone arrays. After the same surface modification, it shows superhydrophobicity with high adhesion. The different adhesive behaviors on the two lock-and-key Au structures are ascribed to their different contact modes with a water droplet. Combining the superhydrophobic properties of the two complementary structures, they can be used to transport precious microdroplets without any loss. The bioinspired periodic Au@Ni NAs can also be potentially employed as surface-enhanced Raman scattering (SERS) substrates due to its electromagnetic enhancement effect, especially at the tips of the nanocones. Thus, superhydrophobic, SERS, long-lived, self-cleaning, microtransportation functions are realized on the basis of the two surfaces.


Assuntos
Ouro/química , Nanoestruturas/química , Adesividade , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Propriedades de Superfície , Difração de Raios X
14.
ACS Appl Mater Interfaces ; 7(29): 15716-25, 2015 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-26125300

RESUMO

Micro-/nanoscale noble metal (Ag, Au, and Pt) particle-decorated 3D porous nickel electrodes for hydrogen evolution reaction (HER) in alkaline electrolyte are fabricated via galvanostatic electrodeposition technique. The developed electrodes are characterized by field emission scanning electron microscopy and electrochemical measurements including Tafel polarization curves, cyclic voltammetry, and electrochemical impedance spectroscopy. It is clearly shown that the enlarged real surface area caused by 3D highly porous dendritic structure has greatly reinforced the electrocatalytic activity toward HER. Comparative analysis of electrodeposited Ag, Au, and Pt particle-decorated porous nickel electrodes for HER indicates that both intrinsic property and size of the noble metal particles can lead to distinct catalytic activities. Both nanoscale Au and Pt particles have further reinforcement effect toward HER, whereas microscale Ag particles exhibit the reverse effect. As an effective 3D hydrogen evolution cathode, the nanoscale Pt-particle-decorated 3D porous nickel electrode demonstrates the highest catalytic activity with an extremely low overpotential of -0.045 V for hydrogen production, a considerable exchange current density of 9.47 mA cm(-2) at 25 °C, and high durability in long-term electrolysis, all of which are attributed to the intrinsic catalytic property and the extremely small size of Pt particles.

15.
Coron Artery Dis ; 26(4): 296-300, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25714070

RESUMO

OBJECTIVE: Plasma nuclear and mitochondrial DNA (mtDNA) levels are altered in many diseases. However, it is not known whether they are also altered in acute myocardial infarction (AMI). In the present study, we examined plasma nuclear and mtDNA levels in the patients with AMI before and after a percutaneous coronary intervention (PCI) to explore their potential as biomarkers. METHODS AND RESULTS: Plasma nuclear and mtDNA levels were measured by quantitative PCR in 25 AMI patients, 25 non-myocardial infarction (MI) control participants (with MI risk), and 20 healthy individuals during the study period. The concentrations of nuclear and mtDNA were significantly higher in the AMI group on hospital day 1 than that in the non-MI controls (nuclear: 0.4948±0.0830 vs. 0.2047±0.0222 ng/µl, P<0.05; mitochondrial: 3.754±0.384 vs. 1.851±0.3483 ng/µl, P<0.05) and healthy individuals (nuclear: 0.4948±0.0830 vs. 0.1683±0.0254 ng/µl, P=0.001; mitochondrial: 3.754±0.384 vs. 0.1517±0.0924 ng/µl, P<0.05) and decreased shortly after PCI. CONCLUSION: Both plasma nuclear and mtDNA levels are elevated in AMI patients, but return to normal levels immediately after PCI, suggesting that they are potentially novel biomarkers for AMI.


Assuntos
Núcleo Celular/genética , DNA Mitocondrial/sangue , DNA/sangue , Infarto do Miocárdio/genética , Biomarcadores/sangue , Humanos
16.
Nanomicro Lett ; 7(4): 347-352, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-30464981

RESUMO

In this work, three-dimensional hierarchical nickel-cobalt alloy coating for hydrogen evolution cathode was fabricated by electrodeposition processes. The coatings' morphology evolves from sea cucumber-like nanostructure to caterpillar-like one with the increase of cobalt content. A large amount of nanometric "steps," served as the active sites for hydrogen evolution reaction, were observed. According to Tafel polarization measurements, the exchange current density of the as-synthesized coating with hierarchical nanostructure was 21.9 times compared with that of flat nickel coating. In addition, the hierarchical coating also displayed good electrochemical stability from the galvanostatic test.

17.
Nanoscale ; 6(16): 9720-6, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-24995507

RESUMO

Silver films with different morphologies were chemically deposited by controlling the bath composition. It is found that the wettability and surface enhanced Raman scattering (SERS) properties were closely connected with the surface morphology. Due to the perfect 3D morphology and the 3D electromagnetic field enhanced by three types of nanogaps distributed uniformly, the 3D microball/nanosheet (MN) silver film shows better SERS properties than those of 2D nanosheets (NSs) and nanoparticles (NPs). The MN silver film showed high adhesive superhydrophobic properties after an oxidation process without any functionalization. It can hold the liquid droplet and trace the target molecules in a rather small volume. The SERS properties of the oxidized MN substrate were enhanced remarkably compared to those of the freshly prepared substrate because of the concentrating effect of the superhydrophobicity. The as-prepared 3D MN silver substrate has also exhibited good performances in reproducibility and reutilization which makes it a promising substrate for molecule tracing.

18.
Chem Commun (Camb) ; 50(61): 8405-7, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-24946911

RESUMO

Lotus leaf-like and petal-like substrates were fabricated by chemical deposition, which have quite different superhydrophobic properties. Excellent, non-sticky, self-cleaning and durable properties were obtained based on the lotus leaf-like substrate.


Assuntos
Prata/química , Interações Hidrofóbicas e Hidrofílicas , Lotus/química , Nanoestruturas/química , Espectroscopia Fotoeletrônica , Folhas de Planta/química , Propriedades de Superfície , Molhabilidade
19.
Chem Commun (Camb) ; 50(67): 9473-6, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-24969077

RESUMO

Hollow nitrogen-doped carbon spheres (HNCSs) were prepared by a facile method as non-precious catalysts for the oxygen reduction reaction (ORR). The HNCS catalysts exhibited ORR activity comparable with a commercial Pt/C catalyst and superior stability in alkaline electrolyte medium.

20.
Chem Commun (Camb) ; 49(88): 10391-3, 2013 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-24072017

RESUMO

Non-sticky and highly adhesive superhydrophobic microball-nanosheet hierarchically structured silver films were obtained after surface modification and storage respectively.

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