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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 225: 117484, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31521003

RESUMO

The interaction of plasmonic nanoparticles with a dielectric platform gives rise to unique optical behaviors and this can be maneuvered to improve the plasmonic/SERS performances of a substrate. Herein, dielectric modified plasmonic-paper SERS substrate is developed by assembling Ag@SiO2 nanocubes on Fe-TiO2 nanosheets (NS) modified paper. The Fe-TiO2 NS being visible light responsive significantly alters the optical property of the paper and serves as a dielectric underlay for the Ag nanocubes. Hence, the incident light reflected back from the dielectric nanosheets couples with the scattered light from the Ag nanocubes leading to spatially enhanced electromagnetic field improving the SERS enhancement. The prepared dielectric modified plasmonic-paper has an average enhancement factor (EF) of 1.49 × 107 using R6G as a probe molecule. This value is superior to unmodified plasmonic-paper highlighting the coupling effect of the dielectric nanosheets. The substrate shows robust detection performance for thiabendazole and achieves a limit of detection (LOD) of 19 µg/L, which is 4-fold more sensitive than unmodified plasmonic paper. Direct swabbing test of thiabendazole sprayed apple fruit shows a discernible Raman signal down to 15 ppb indicating the utility of the substrate for point-of-need applications in food safety.

2.
Eur J Cardiovasc Nurs ; 18(8): 658-666, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31232097

RESUMO

BACKGROUND: Stroke, a medical condition that causes physical disability and mental health problems, impacts negatively on quality of life. Post-stroke rehabilitation is critical to restoring quality of life in these patients. OBJECTIVES: This study was designed to evaluate the effect of a mind-body interactive qigong intervention on the physical and mental aspects of quality of life, considering bio-physiological and mental covariates in subacute stroke inpatients. METHODS: A randomized controlled trial with repeated measures design was used. A total of 68 participants were recruited from the medical and rehabilitation wards at a teaching hospital in northern Taiwan and then randomly assigned either to the Chan-Chuang qigong group, which received standard care plus a 10-day mind-body interactive exercise program, or to the control group, which received standard care only. Data were collected using the National Institutes of Health Stroke Scale, Hospital Anxiety and Depression Scale, Short Form-12, stroke-related neurologic deficit, muscular strength, heart rate variability and fatigue at three time points: pre-intervention, halfway through the intervention (day 5) and on the final day of the intervention (day 10). RESULTS: The results of the mixed-effect model analysis showed that the qigong group had a significantly higher quality of life score at day 10 (p<0.05) than the control group. Among the covariates, neurologic deficit (p=0.04), muscle strength (p=0.04), low frequency to high frequency ratio (p=0.02) and anxiety (p=0.04) were significantly associated with changes in quality of life. Conversely, heart rate, heart rate variability (standard deviation of normal-to-normal intervals, low frequency and high frequency), fatigue and depression were not significantly associated with change in quality of life (p >0.05). CONCLUSIONS: This study supports the potential benefits of a 10-day mind-body interactive exercise (Chan-Chuang qigong) program for subacute stroke inpatients and provides information that may be useful in planning adjunctive rehabilitative care for stroke inpatients.

3.
J Microbiol Immunol Infect ; 52(4): 556-562, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30360951

RESUMO

BACKGROUND: In Taiwan, the majority of chronic hepatitis C carriers with HIV co-infection are intravenous drug users and inmates in correctional facilities. Peginterferon and ribavirin (PegIFN/RBV) have been the standard-of-care for chronic hepatitis C virus (HCV) infection more than decades. We evaluated the estimated cost-effectiveness of PegIFN/RBV from the National Health Insurance Research Database, covering the population of Taiwan from 1998 to 2013. MATERIALS AND METHODS: This is an observational study, and study during was 2010-2016 and a total of 239 patients were treated with PegIFN/RBV. Of them, 156 patients were treated in the correctional facilities of Taipei, Taoyuan, Taichung and Taitung prisons, and 83 patients were treated in communities. The cost-effectiveness was analyzed in regimens of PegIFN/RBV and direct-acting antiviral agents. RESULTS: By multivariate analysis, the patients completed PegIFN/RBV in prison (adjusted odds ratio [aOR]: 4.56, 95% confidence interval [CI]: 1.58-13.12, p = 0.005), HCV RNA level <800,000 IU/mL (aOR: 4.0, 95% CI: 1.27-12.66, p = 0.02) at baseline, and the presence of early virologic response (EVR) (aOR: 7.67, 95% CI: 1.89-31.06, p = 0.004) were independent predictors for sustained virologic response (SVR). For the subgroups of prisoners, HIV-infected prisoners and HIV-infected patients in communities, the SVR rate was 73.8%, 72.0% and 36.8%, and the average medical-care cost was US$7,701, $7,893, and $15,443 per SVR achieved, respectively. Also, the estimated medical-care cost for genotype 6 was US$9211. CONCLUSIONS: Chronic HCV/HIV co-infected patients with genotype 1 and 6 in the community setting could benefit from DAAs in Taiwan.


Assuntos
Antivirais/economia , Coinfecção/economia , Análise Custo-Benefício , Infecções por HIV/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Prisões , Ribavirina/economia , Adulto , Antivirais/uso terapêutico , Coinfecção/tratamento farmacológico , Quimioterapia Combinada/economia , Feminino , Genótipo , Infecções por HIV/complicações , Custos de Cuidados de Saúde , Hepatite C Crônica/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ribavirina/uso terapêutico , Taiwan , Carga Viral
4.
Anal Chem ; 90(12): 7283-7291, 2018 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-29787232

RESUMO

Stereospecific recognition of chiral molecules is ubiquitous in chemical and biological systems, thus leading to strong demand for the development of enantiomeric drugs, enantioselective sensors, and asymmetric catalysts. In this study, we demonstrate the ratio of d-Cys and l-Cys playing an important role in determining the optical properties and the structures of self-assembled Cys-Au(I) supramolecules prepared through a simple reaction of tetrachloroaurate(III) with chiral cysteine (Cys). The irregularly shaped -[d-Cys-Au(I)] n- or - [l-Cys-Au(I)] n- supramolecules with a size larger than 500 nm possessing strong absorption in the near-UV region and chiroptical characteristics were only obtained from the reaction of Au(III) with d-Cys or l-Cys. On the other hand, spindle-shaped -[d/l-Cys-Au(I)] n- supramolecules were formed when using Au(III) with mixtures of d/l-Cys. Our results have suggested that Au(I)···Au(I) aurophilic interactions, and stacked hydrogen bonding and zwitterionic interactions between d/l-Cys ligands are important in determining their structures. The NaBH4-mediated reduction induces the formation of photoluminescent gold nanoclusters (Au NCs) embedded in the chiral -[d-Cys-Au(I)] n- or -[l-Cys-Au(I)] n- supramolecules with a quantum yield of ca. 10%. The as-formed Au NCs/-[d-Cys-Au(I)] n- and Au NCs/-[l-Cys-Au(I)] n- are an enantiospecific substrate that can trap l-carnitine and d-carnitine, respectively, and function as a nanomatrix for surface-assisted laser desorption/ionization mass spectrometry (LDI-MS). The high absorption efficiency of laser energy, analyte-binding capacity, and homogeneity of the Au NCs/-[Cys-Au(I)] n- allow for quantitation of enantiomeric carnitine down to the micromolar regime with high reproducibility. The superior efficiency of the Au NCs/-[d-Cys-Au(I)] n- substrate has been further validated by quantification of l-carnitine in dietary supplements with accuracy and precision. Our study has opened a new avenue for chiral quantitation of various analytes through LDI-MS using metal nanocomposites consisting of NCs and metal-ligand complexes.


Assuntos
Carnitina/análise , Nanocompostos/química , Cisteína/química , Ouro/química , Lasers , Reprodutibilidade dos Testes , Estereoisomerismo
5.
Sci Rep ; 8(1): 6062, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29643348

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

6.
Liver Int ; 38(4): 627-635, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28857411

RESUMO

BACKGROUND & AIMS: The kinetics of serum hepatitis B surface antigen (HBsAg) levels during long-term nucleos(t)ide analogue (NA) therapy in chronic hepatitis B (CHB) patients remains unclear. We investigated the patterns of serum HBsAg kinetics and their association with therapeutic outcomes in genotype B- or C-infected CHB patients receiving long-term NA therapy. METHODS: We enrolled 329 treatment-naive CHB patients receiving NA therapy for >5 years to analyse the kinetic patterns by using group-based trajectory models (GBTMs). RESULTS: Most patients (82.4%) received entecavir therapy. The median treatment duration was 83.6 (68.5-89.7) months. The GBTMs revealed three groups for both the hepatitis B e antigen (HBeAg)-positive and -negative patients. The median annual decline in serum HBsAg levels during the first 5 years was significantly higher in Group 1 than in Groups 2 and 3 in HBeAg-positive (0.78 vs 0.10 vs 0.10 log10 IU/mL) and HBeAg-negative (0.71 vs 0.08 vs 0.09 log10 IU/mL) patients. HBsAg levels at the baseline and 12 months combined with an HBsAg decline from the baseline to 12 months of treatment predicted trajectory pattern 1 in HBeAg-positive (sensitivity, 77.8%; specificity, 99.1%; positive predictive value [PPV], 87.5%; and negative predictive value [NPV], 98.2%) and HBeAg-negative (sensitivity, 100%; specificity, 99.5%; PPV, 88.9%; and NPV, 100%) patients. The trajectory patterns were significantly associated with HBeAg loss in the HBeAg-positive patients and the achievement of HBsAg <100 IU/mL or HBsAg loss in HBeAg-positive and HBeAg-negative patients. CONCLUSIONS: The trajectory of serum HBsAg levels predicts HBsAg loss in CHB patients receiving long-term NA therapy.


Assuntos
Antivirais/administração & dosagem , Guanina/análogos & derivados , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Adulto , DNA Viral/sangue , Feminino , Guanina/administração & dosagem , Vírus da Hepatite B/genética , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Sensibilidade e Especificidade , Taiwan
7.
ACS Omega ; 3(12): 16576-16584, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31458290

RESUMO

Roughing the metallic surface via oxidation-reduction cycles (ORC) to integrate the surface plasmon resonance and surface-enhanced Raman scattering (SERS) is predominant in developing sensor systems because of the facile preparation and uniform distribution of nanostructures. Herein, we proposed a distinctive ORC process: the forward potential passed through the oxidation of Au and reached the oxygen evolution reaction, and once the potential briefly remained at the vertex, the various reverse rates were employed to control the reduction state. The created hybrid Au-AuO x possessed electromagnetic and chemical enhancements concurrently, wherein the rough surface provided the strong local electromagnetic fields and significant interaction between AuO x and molecule to improve the charge transfer. The synergistic effects significantly amplified the intensity of Raman signal with an enhancement factor of 5.5 × 106 under the optimal conditions. Furthermore, the prepared SERS substrate can simultaneously identify and quantify the mixed edible pigments, Brilliant Blue FCF and Indigo Carmine, individually. This result suggested that the development of SERS sensor based on the proposed SERS-activated methodology is feasible and reliable.

8.
Sci Rep ; 7(1): 3259, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28607450

RESUMO

We developed an optimal noninvasive index comprising routine laboratory parameters for predicting cirrhosis in chronic hepatitis B (CHB) and chronic hepatitis C (CHC) patients. This study included 992 CHB patients and 1,284 CHC patients who received liver biopsy. We developed the new index, named modified Fibrosis-4 (mFIB-4) according to four independent variables of the model: age, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and platelet count. The formula of the mFIB-4 index is 10 × Age(years) × AST(U/L)/Platelet count(109/L) × AST(U/L). For predicting cirrhosis, the bootstrap areas under the receiver operating characteristic curve for platelet count, AST/ALT ratio (AAR), AAR/platelet ratio index (AARPRI), AST/platelet ratio index (APRI), FIB-4, Pohl score, age-platelet (AP) index, Lok index, fibrosis quotient (FibroQ), and mFIB-4 were 0.7680, 0.7400, 0.8070, 0.6090, 0.7690, 0.6990, 0.7850, 0.7960, 0.8110, and 0.8070 in CHB patients, and 0.8170, 0.7210, 0.8400, 0.7310, 0.8310, 0.6730, 0.8220, 0.8440, 0.8570, and 0.8480 in CHC patients, respectively. FibroQ and mFIB-4 exhibited the highest diagnostic performance levels for liver cirrhosis in CHB and CHC despite the inclusion of the international normalised ratio in the formulation of FibroQ. Thus, mFIB-4 is a simple, inexpensive, and readily available method for assessing the liver fibrosis stage of Asian patients with CHB or CHC.


Assuntos
Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Adulto , Fatores Etários , Idoso , Alanina Transaminase/sangue , Grupo com Ancestrais do Continente Asiático , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Biópsia , Feminino , Hepatite B Crônica/sangue , Hepatite C Crônica/sangue , Humanos , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas
9.
Biosens Bioelectron ; 96: 167-172, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28494368

RESUMO

The binding of organometallic osmium carbonyl clusters onto the surface of gold nanoparticles (10OsCO-Au NPs) greatly enhanced the CO stretching vibration signal at ~2100cm-1, which is relatively free from interference due to the absorbance of biomolecules. By utilizing the acetylcholinesterase (AChE) mediated hydrolysis of acetylthiocholine to thiocholine where the activity of AChE is inhibited by the presence of organophosphate pesticides (OPPs), the subsequent thiocholine-induced aggregation of 10OsCO-Au NPs can be monitored by the change in color of the NPs solution and the variation in intensity of the SERS CO signal. The change in color offers a fast pre-screening method, whereas monitoring via SERS is used for greater accuracy and lower limit of detection (0.1 ppb) for quantitative detection. Its potential as a quick and accurate method of OPPs monitoring in consumer products was demonstrated in the detection of OPPs in real spiked samples such as beer.


Assuntos
Análise de Alimentos/métodos , Ouro/química , Nanopartículas Metálicas/química , Compostos Organofosforados/análise , Praguicidas/análise , Ressonância de Plasmônio de Superfície/métodos , Acetilcolinesterase/química , Acetiltiocolina/química , Cerveja/análise , Glicina/análogos & derivados , Glicina/análise , Hidrólise , Nanopartículas Metálicas/ultraestrutura , Tiocolina/química
10.
Phys Chem Chem Phys ; 19(19): 12085-12093, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28443925

RESUMO

In this study, we prepared photoluminescent l-cysteine (Cys)-capped gold nanoclusters (Cys-Au NCs) via NaBH4-mediated reduction of aggregated coordination polymers (supramolecules) of -[Cys-Au(i)]n-. The -[Cys-Au(i)]n- supramolecules with interesting chiral properties were formed through simple reactions of chloroauric acid (HAuCl4) with Cys at certain pH values (pH 3-7). The -[Cys-Au(i)]n- polymers could self-assemble into -[Cys-Au(i)]n- supramolecules with irregular morphologies and diameters larger than 500 nm through stacked hydrogen bonding and zwitterionic interactions between Cys ligands and through Au(i)Au(i) aurophilic interactions in solutions with pH values ≤7. The photoluminescent Au NCs (quantum yield = 11.6%) dominated by a Au13 core were embedded in -[Cys-Au(i)]n- supramolecules after NaBH4-mediated reduction. The optical and structural properties of Cys-Au NCs/-[Cys-Au(i)]n- nanocomposites were investigated, revealing that the interaction between Cys ligands plays a critical role in the self-assembly of -[Cys-Au(i)]n- supramolecules and in the formation of photoluminescent Cys-Au NCs embedded in the supramolecules. To further demonstrate that the photoluminescence properties and structures of the nanocomposites are mediated by the intermolecular forces of thiol ligands, other thiol ligands (l-penicillamine, l-homocysteine, 3-mercaptopropionic acid, and l-glutathione) and a ligand-crosslinking agent [bis(sulfosuccinimidyl) suberate; BS3] were used. We concluded that the electrostatic interactions, hydrogen bonding and steric effects dominate the polymer self-assembly into thiol-ligand-Au(i) supramolecules and thus the formation of Au NCs. Our study provides insights into the bottom-up synthesis of photoluminescent Au NCs from thiol-ligand-Au(i) complexes, polymers, and supramolecules. The hybrid Au NCs/-[Cys-Au(i)]n- nanocomposites can potentially be employed as drug carriers and bioimaging agents.


Assuntos
Ouro/química , Ligantes , Nanopartículas Metálicas/química , Cloretos/química , Compostos de Ouro/química , Concentração de Íons de Hidrogênio , Luz , Luminescência , Oxirredução , Polímeros
11.
ACS Nano ; 11(3): 3365-3375, 2017 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-28245103

RESUMO

Matrix metalloproteinases (MMPs), specifically MMP-2, MMP-7, and MMP-9, have been discovered to be linked to many forms of vascular diseases such as stroke, and their detection is crucial to facilitate clinical diagnosis. In this work, we prepared a class of optical interference-free SERS nanotags (CO-nanotags) that can be used for the purpose of multiplex sensing of different MMPs. Multiplex detection with the absence of cross-talk was achieved by using CO-nanotags with individual tunable intrinsic Raman shifts of CO in the 1800-2200 cm-1 region determined by the metal core and ligands of the metal carbonyl complex. Boolean logic was used as well to simultaneously probe for two proteolytic inputs. Such nanotags offer the advantages of convenient detection of target nanotags and high sensitivity as validated in the ischemia rat model.


Assuntos
Monóxido de Carbono/química , Metaloproteinases da Matriz/sangue , Nanopartículas/química , Compostos Organometálicos/química , Doenças Vasculares/diagnóstico por imagem , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Ligantes , Masculino , Metaloproteinases da Matriz/metabolismo , Fenômenos Ópticos , Tamanho da Partícula , Ratos , Ratos Wistar , Propriedades de Superfície , Doenças Vasculares/sangue , Doenças Vasculares/metabolismo
12.
Sci Rep ; 7: 42879, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28220833

RESUMO

Early declines in serum hepatitis B surface (HBsAg) levels, their optimal cutoffs, and association with therapeutic endpoints in chronic hepatitis B (CHB) patients receiving entecavir treatment remain unclear. We prospectively enrolled 529 patients (195 hepatitis B e antigen [HBeAg]-positive and 334 HBeAg-negative) with a median treatment duration of 49.2 months. Median HBsAg levels declined significantly in both groups at Month 3, but only at Months 6-12 in the HBeAg-negative group. Both groups exhibited a significant HBsAg decline with each successive year of treatment. An HBsAg decline of ≥75% from baseline, assessed at Months 3 and 12 of treatment in the HBeAg-positive and -negative patients, respectively, independently predicted a virological response and HBeAg seroconversion in the HBeAg-positive patients, an HBsAg level of <100 IU/mL in the HBeAg-negative patients, and HBsAg loss in all the patients during treatment. HBsAg levels of <3,000 IU/mL at baseline combined with an HBsAg decline of ≥75% from baseline provided a predictive algorithm for HBsAg loss (positive and negative predictive values: 70% and 100%, respectively) during 5 years of treatment. The proposed cutoffs for defining an HBsAg decline may assist clinicians in early assessments of treatment responses in genotype B-infected or C-infected CHB patients receiving entecavir therapy.


Assuntos
Antivirais/uso terapêutico , Guanina/análogos & derivados , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/tratamento farmacológico , Adulto , Idoso , Feminino , Genótipo , Guanina/uso terapêutico , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Resultado do Tratamento
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 175: 239-245, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28043067

RESUMO

Surface-enhanced Raman scattering (SERS) and fluorescence microscopy are a widely used biological and chemical characterization techniques. However, the peak overlapping in multiplexed experiments and rapid photobleaching of fluorescent organic dyes is still the limitations. When compared to Ag nanocubes (NCs), higher SERS sensitivities can be obtained with thin shelled silica Ag@SiO2 NCs, in contrast metal-enhanced photoluminescence (MEPL) is only found with NCs that have thicker silica shells. A 'dual functionality' represented by the simultaneous strengthening of SERS and MEPL signals can be achieved by mixing Ag@SiO2 NCs, with a silica shell thickness of ~1.5nm and ~4.4nm. This approach allows both the Ag@SiO2 NCs SERS and MEPL sensitivities to be maintained at ~90% after 12weeks of storage. Based on the distinguished detection of creatinine and flavin adenine dinucleotide in the mixture, the integration of SERS and MEPL together on a stable single plasmonic nanoparticle platform offers an opportunity to enhance both biomarker detection sensitivity and specificity.


Assuntos
Creatinina/análise , Flavina-Adenina Dinucleotídeo/análise , Medições Luminescentes , Nanopartículas Metálicas/química , Dióxido de Silício/química , Prata/química , Análise Espectral Raman , Nanopartículas Metálicas/ultraestrutura , Espectrometria por Raios X , Coloração e Rotulagem , Difração de Raios X
14.
Sci Rep ; 7: 40896, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-28102314

RESUMO

Hydrogenated titanium dioxide has attracted intensive research interests in pollutant removal applications due to its high photocatalytic activity. Herein, we demonstrate hydrogenated TiO2 nanofibers (H:TiO2 NFs) with a core-shell structure prepared by the hydrothermal synthesis and subsequent heat treatment in hydrogen flow. H:TiO2 NFs has excellent solar light absorption and photogenerated charge formation behavior as confirmed by optical absorbance, photo-Kelvin force probe microscopy and photoinduced charge carrier dynamics analyses. Photodegradation of various organic dyes such as methyl orange, rhodamine 6G and brilliant green is shown to take place with significantly higher rates on our novel catalyst than on pristine TiO2 nanofibers and commercial nanoparticle based photocatalytic materials, which is attributed to surface defects (oxygen vacancy and Ti3+ interstitial defect) on the hydrogen treated surface. We propose three properties/mechanisms responsible for the enhanced photocatalytic activity, which are: (1) improved absorbance allowing for increased exciton generation, (2) highly crystalline anatase TiO2 that promotes fast charge transport rate, and (3) decreased charge recombination caused by the nanoscopic Schottky junctions at the interface of pristine core and hydrogenated shell thus promoting long-life surface charges. The developed H:TiO2 NFs can be helpful for future high performance photocatalysts in environmental applications.

15.
Sci Rep ; 6: 22166, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26916099

RESUMO

The strength of hydrogen bond (HB) decides water's property and activity. Here we propose the mechanisms on creation and persistence of innovatively prepared liquid water, which is treated by Au nanoparticles (AuNPs) under resonant illumination of green-light emitting diode (LED) to create Au NP-treated (sAuNT) water, with weak HB at room temperature. Hot electron transfer on resonantly illuminated AuNPs, which is confirmed from Au LIII-edge X-ray absorption near edge structure (XANES) spectra, is responsible for the creation of negatively charged sAuNT water with the incorporated energy-reduced hot electron. This unique electronic feature makes it stable at least for one week. Compared to deionized (DI) water, the resulting sAuNT water exhibits many distinct properties at room temperature. Examples are its higher activity revealed from its higher vapor pressure and lower specific heat. Furthermore, Mpemba effect can be successfully explained by our purposed hypothesis based on sAuNT water-derived idea of water energy and HB.

16.
Biosens Bioelectron ; 77: 1086-94, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26556186

RESUMO

The nanopatterning of gold nanoparticle (AuNP) arrays on an indium tin oxide (ITO) electrode using efficient and low-cost methods is described. This process used nanosphere lithography (NSL) encompassing the deposition of monolayered Polystyrene (PS) followed by a convective self-assembly drop coating protocol onto the ITO substrate that further acted as the mask after the AuNP assembly. The results showed that spin-coating allowed AuNPs to follow the contour and adhere to the PS nanospheres. The final products, after etching the PS, generated a highly ordered Au-nanohole array on an ITO substrate. The Au-nanohole arrays on the ITO electrode provided a greater surface area and successfully enhanced the peak current of electrochemical measurements by 82% compared with bare ITO and was used to detect Staphylococcus aureus 16S rRNA hybridization. In contrast to non-templated AuNP structures, the Au-nanohole arrays on the ITO electrode contributed to an optimum sensitivity improvement in DNA hybridization detection by 23%, along with an impressive limit of detection (LOD) of 10 pM. The high specificity of this distinguished structure was also achieved in the hybridization measurements of multi-analyte pathogens. These findings indicate that the combination of PS nanosphere lithography, followed by the spin-coating of AuNPs, leads to an inexpensive and simple engineering process that effectively generates uniform Au-nanohole arrays on ITO, which provides a greater surface area to optimize the electrochemical performance of the DNA biosensor.


Assuntos
Técnicas Biossensoriais/instrumentação , Nanopartículas Metálicas/química , Nanoporos/ultraestrutura , RNA Ribossômico 16S/genética , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Desenho de Equipamento , Análise de Falha de Equipamento , Ouro/química , Impressão Molecular/métodos , RNA Ribossômico 16S/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Sci Rep ; 5: 13671, 2015 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-26329829

RESUMO

High threading dislocation (TD) density in GaN-based devices is a long unresolved problem because of the large lattice mismatch between GaN and the substrate, which causes a major obstacle for the further improvement of next-generation high-efficiency solid-state lighting and high-power electronics. Here, we report InGaN/GaN LEDs with ultralow TD density and improved efficiency on a sapphire substrate, on which a near strain-free GaN compliant buffer layer was grown by remote plasma atomic layer deposition. This "compliant" buffer layer is capable of relaxing strain due to the absorption of misfit dislocations in a region within ~10 nm from the interface, leading to a high-quality overlying GaN epilayer with an unusual TD density as low as 2.2 × 10(5) cm(-2). In addition, this GaN compliant buffer layer exhibits excellent uniformity up to a 6" wafer, revealing a promising means to realize large-area GaN hetero-epitaxy for efficient LEDs and high-power transistors.

18.
ACS Appl Mater Interfaces ; 7(30): 16486-94, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26177076

RESUMO

We demonstrate semiconducting polymer-based thin-film transistors (PTFTs) with fast switching performance and an uncommon nondecaying feature. These PTFTs based on widely studied poly(3-hexylthiophene) are developed by incorporating the insulating polymer into the active channel and subjecting the compound to specific, spontaneous multiple-scale phase separation (MSPS). An in-depth study is conducted on the interfacial and phase-separated microstructure of the semiconducting/insulating blending active layer and its effect on the electrical characteristics of PTFTs. The polyblends exhibit a confined crystallization behavior with continuously semiconducting crystalline domains between scattered insulator-rich domains. The insulator-rich domains can block leakage current and strengthen the gate control of the channel. A small amount of the insulating polymer penetrates the bottom of the active channel, resulting in effective interface modification. We show specific MSPS morphology of the present blending films to reduce charge trapping effects, enhance charge accumulation, and create a high-seed switching channel. The findings enable us to develop the required morphological conceptual model of the ideal-like field-effect-modulated polymer-based active channel. The polyblend-based PTFTs with MSPS morphology also have promising sensing functions. This study offers an effective approach for overcoming the major drawbacks (instability and poor switching) of PTFTs, thus allowing such transistors to have potential applications.

19.
Hepat Mon ; 15(3): e27148, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25834588

RESUMO

BACKGROUND: Single-nucleotide polymorphisms (SNP) in the inosine triphosphate pyrophosphatase (ITPA) gene correlate with ribavirin (RBV)-induced anemia in patients with chronic hepatitis C (CHC) receiving combination therapy. Managing anemia is an early priority in the treatment process. OBJECTIVES: The aim was to develop a predictive index based on ITPA SNP status to identify CHC patients at risk of anemia. PATIENTS AND METHODS: A total of 418 eligible East Asian patients diagnosed with CHC genotype 1 (G1) received combination therapy in this study. Participant DNA was genotyped for a functional ITPA SNP (C/C, A/A or C/A) on chromosome 20 at rs1127354. A predictive index was constructed by incorporating independent factors identified for severe anemia events (hemoglobin < 10 g/dL). Areas under the receiver-operating characteristic curves (AUCs) represented the diagnostic accuracies of the predictive index in randomly assigned development and validation cohorts. RESULTS: Multiple logistic regressions identified age (≥ 50 y: OR = 9.7, 95% CI = 5.0 - 18.6), ITPA rs1127354 (C/C: OR = 3.3, 95% CI = 1.8 - 5.8) and baseline hemoglobin (< 14.0 g/dL: OR 6.4, 95% CI = 3.3 - 12.1; 14.0 - 14.9: OR = 2.4, 95% CI = 1.2 - 4.6) as predictors of severe anemia throughout the treatment. For severe anemia, the predictive index incorporating age, ITPA SNP status and baseline hemoglobin yielded diagnostic accuracies (AUCs) of 0.830 (95% CI = 0.783 - 0.871) in the development (n = 324) and 0.902 (0.826 - 0.925) in the validation (n = 81) cohorts. CONCLUSIONS: In patients with CHC G1 and receiving combination therapy, ITPA SNP-based index was an accurate and practical solution for prediction of severe anemia.

20.
Anal Chim Acta ; 867: 83-91, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25813031

RESUMO

A water-dispersible multi-walled carbon nanotubes (MWCNTs) derivative, MWCNTs-1-one-dihydroxypyridine (MWCNTs-Py) was synthesis via Friedel-Crafts chemical acylation. Raman spectra demonstrated the conjugated level of MWCNTs-Py was retained after this chemical modification. MWCNTs-Py showed dual hydrogen peroxide (H2O2) and glucose detections without mutual interference by adjusting pH value. It was sensitive to H2O2 in acidic solution and displayed the high performances of sensitivity, linear range, response time and stability; meanwhile it did not respond to H2O2 in neutral solution. In addition, this positively charged MWCNTs-Py could adsorb glucose oxidase (GOD) by electrostatic attraction. MWCNTs-Py-GOD/GC electrode showed the direct electron transfer (DET) of GOD with a pair of well-defined redox peaks, attesting the bioactivity of GOD was retained due to the non-destroyed immobilization. The high surface coverage of active GOD (3.5×10(-9) mol cm(-2)) resulted in exhibiting a good electrocatalytic activity toward glucose. This glucose sensor showed high sensitivity (68.1 µA mM(-1) cm(-2)) in a linear range from 3 µM to 7 mM in neutral buffer solution. The proposed sensor could distinguish H2O2 and glucose, thus owning high selectivity and reliability.


Assuntos
Técnicas Biossensoriais/métodos , Glucose Oxidase/metabolismo , Glucose/análise , Peróxido de Hidrogênio/análise , Nanotubos de Carbono/química , Água/química , Técnicas Biossensoriais/instrumentação , Glicemia/análise , Glicemia/química , Ácidos Carboxílicos/química , Eletroquímica , Eletrodos , Transporte de Elétrons , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Vidro/química , Glucose/química , Glucose Oxidase/química , Humanos , Peróxido de Hidrogênio/química , Piridinas/química
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