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1.
Cell Rep Methods ; : 100754, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38614089

RESUMO

Precision medicine's emphasis on individual genetic variants highlights the importance of haplotype-resolved assembly, a computational challenge in bioinformatics given its combinatorial nature. While classical algorithms have made strides in addressing this issue, the potential of quantum computing remains largely untapped. Here, we present the vehicle routing problem (VRP) assembler: an approach that transforms this task into a vehicle routing problem, an optimization formulation solvable on a quantum computer. We demonstrate its potential and feasibility through a proof of concept on short synthetic diploid and triploid genomes using a D-Wave quantum annealer. To tackle larger-scale assembly problems, we integrate the VRP assembler with Google's OR-Tools, achieving a haplotype-resolved local assembly across the human major histocompatibility complex (MHC) region. Our results show encouraging performance compared to Hifiasm with phasing accuracy approaching the theoretical limit, underscoring the promising future of quantum computing in bioinformatics.

2.
Small ; : e2307350, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38072806

RESUMO

Hydrogen (H2 ), the most abundant element in the universe, has the potential to address the challenges of energy security and climate change. However, due to the lack of a safe and efficient method for storing and delivering hydrogen, its practical application is still in its infancy stages. To overcome this challenge, a promising solution is demonstrated in the form of on-demand production of H2 using nano-Silicon (Si) powders. The method offers instantaneous production of H2 , yielding a volume of 1.3 L per gram of Si at room temperature. Moreover, the H2 production yield and the rate can be effectively controlled by adjusting the reaction pH value and temperatures. Additionally, liquid-phase transmission electron microscopy (LPTEM) is utilized in situ to demonstrate the entire reaction in real-time, wherein H2 bubble formation is observed and illustrated the gradual conversion of crystalline Si particles into amorphous oxides. Moreover, it is confirmed that the purity of the generated gas is 99.5% using gas chromatography mass spectrometry (GC-MS). These findings suggest a viable option for instant H2 production in portable fuel cells using Si cartridges or pellets.

3.
ACS Appl Mater Interfaces ; 15(15): 18845-18856, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37039341

RESUMO

High C-rate capability at 10C is a key performance indicator for the commercialization of the next-generation high-charging lithium microbattery. However, silicon (Si) anode satisfying the prerequisite high specific capacity suffers from poor electron/ionic conductivity, seriously limiting the 10C rate capability. Accordingly, we propose the strategy of inserting highly conductive silver nanoparticles (AgNPs) as an interlayer between two RF-sputtered amorphous Si thin films to form an Si/Ag/Si multilayered anode, with the density and spatial distribution of the AgNPs well-controlled by thermal evaporation. This strategy is exclusively beneficial to scale up film thickness for higher capacity. Without AgNPs, the 10C rate performance of the double-layer Si (D_Si) is worse than the single layer (S_Si) in the same total thickness, suggesting the adverse effect of the interface. However, this situation is progressively improved with the AgNPs density incorporated at the interface, where the densest AgNPs anode (D_SiAg3) demonstrated a noticeable improvement reaching 1250 mAh/g at 10 C with a 46% capacity retention rate. By scaling up to triple layers, T_SiAg3 performed the superior 10C rate capability to T_Si, testifying to the scalable potential of the unique design for boosting high-power batteries. Finally, with electrochemical impedance spectroscopy results, a possible mechanism to explain the enhancement in rate capability is subject to where Li-ion diffusion is accelerated by the charge-induced electric field condensing around the AgNPs. This design for a multilayered nanocomposite can contribute to the design and fabrication of high-charging batteries and battery-on-chip.

4.
Medicine (Baltimore) ; 98(44): e17541, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689755

RESUMO

BACKGROUND: Previous clinical trials indicated that duloxetine may be effective in the treatment of osteoarthritis (OA) pain. This meta-analysis is conducted to evaluate short term analgesic effect and safety of duloxetine in the treatment of OA. METHODS: Electronic databases were searched in February 2019, including PUBMED, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Web of Science. All eligible studies should be randomized controlled trials (RCTs) comparing duloxetine treatment group to placebo about OA pain relief and safety outcomes. RESULTS: Five RCTs with 2059 patients were involved in this systematic review and meta-analysis. Compared to placebo, duloxetine treatment showed significant better result, with higher reduction pain intensity (mean difference [MD] = -0.77, P < .00001), higher rates of both 30% and 50% reduction in pain severity (risk ratio [RR] = 1.42, P < .00001; RR = 1.62, P < .00001), lower mean Patient Global Improvement-Inventory (PGI-I) score (MD = -0.48, P < .00001). The results of the Western Ontario and McMaster Universities (WOMAC) score change from baseline to endpoint also favored duloxetine treatment group in all four categories, including total (MD = -5.43, P < .00001), pain (MD = -1.63, P = .001), physical function (MD = -4.22, P < .00001), and stiffness score (MD = -0.58, P < .00001). There were higher rates of treatment-emergent adverse events (TEAEs) (RR = 1.32, P < .00001) and discontinuation (RR = 1.88, P < .00001) in duloxetine group. However, there was no significant difference in the incidence of severe adverse events (SAEs) between these 2 groups (RR = 0.84, P = .68). CONCLUSION: Duloxetine was an effective and safe choice to improve pain and functional outcome in OA patients. However, further studies are still needed to find out the optimal dosage for OA and examine its long-term efficacy and safety. TRIAL REGISTRATION NUMBER: CRD42019128862.


Assuntos
Analgésicos/uso terapêutico , Cloridrato de Duloxetina/uso terapêutico , Osteoartrite/tratamento farmacológico , Analgésicos/efeitos adversos , Cloridrato de Duloxetina/efeitos adversos , Humanos , Ontário , Medição da Dor , Gravidade do Paciente , Desempenho Físico Funcional , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Nanoscale ; 8(1): 634-40, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26646378

RESUMO

Surface free energy, as an intrinsic property, is essential in determining the morphology of materials, but it is extremely difficult to determine experimentally. We report on the derivation of the SE of different facets of ZnO and GaN experimentally from the holes developed using electron beam drilling with transmission electron microscopy. Inverse Wullf's construction is employed to obtain polar maps of the SE of different facets to study different nanomaterials (ZnO and GaN) in different morphologies (nanorod, nanobelt and thin film) to prove its versatility and capability. The results show that the SE of ZnO{10-13} is derived to be 0.99 J m(-2), and the SE of ZnO{10-10} is found to be less than {0002} and {11-20}. A GaN thin film also exhibits a similar trend in the SE of different facets as ZnO and the SE of GaN{10-13} is determined to be 1.36 J m(-2).

6.
Sci Rep ; 5: 12533, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26211998

RESUMO

The island nucleation in the context of heterogeneous thin film growth is often complicated by the growth kinetics involved in the subsequent thermodynamics. We show how the evolution of sputtered Zn island nucleation on Si(111) by magnetron sputtering in a large area can be completely understood as a model system by combining reflective second harmonic generation (RSHG), a 2D pole figure with synchrotron X-ray diffraction. Zn dots are then oxidized on the surfaces when exposed to the atmosphere as Zn/ZnO dots. Derived from the RSHG patterns of Zn dots at different growth times, the Zn dots grow following a unique transition from kinetic to thermodynamic control. Under kinetic-favoring growth, tiny Zn dots prefer arranging themselves with a tilted c-axis to the Si(111) substrate toward any of the sixfold in-plane Si<110> directions. Upon growth, the Zn dots subsequently evolve themselves to a metastable state with a smaller tilting angle toward selective <110> directions. As the Zn dots grow over a critical size, they become most thermodynamically stable with the c-axis vertical to the Si(111) substrate. For a system with large lattice mismatch, small volume dots take kinetic pathways with insignificant deviations in energy barriers.

8.
Opt Express ; 20(3): 2015-24, 2012 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-22330442

RESUMO

A combined method of modified oblique-angle deposition and hydrothermal growth was adopted to grow an optically anisotropic nanomaterial based on single crystalline ZnO nanowire arrays (NWAs) with highly oblique angles (75°-85°), exhibiting giant in-plane birefringence and optical polarization degree in emission. The in-plane birefringence of oblique-aligned ZnO NWAs is almost one order of magnitude higher than that of natural quartz. The strong optical anisotropy in emission due to the optical confinement was observed. The oblique-aligned NWAs not only allow important technological applications in passive photonic components but also benefit the development of the optoelectronic devices in polarized light sensing and emission.


Assuntos
Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Ressonância de Plasmônio de Superfície/métodos , Óxido de Zinco/química , Anisotropia , Birrefringência , Luz , Teste de Materiais , Espalhamento de Radiação , Propriedades de Superfície
9.
Nano Lett ; 12(2): 562-8, 2012 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-22208722

RESUMO

This paper proposes an obliquely aligned InN nanorod array to maximize nanorod deformation in the application of nanopiezotronics. The surface-dependent piezotronic I-V characteristics of the InN nanorod array with exposed polar (0002) and semipolar ( ̅1102) planes were studied by conductive atomic force microscopy. The effects of the piezopotential, created in the InN under straining, and the surface quantum states on the transport behavior of charge carriers in different crystal planes of the InN nanorod were investigated. The crystal plane-dependent electron density in the electron surface accumulation layer and the strain-dependent piezopotential distribution modulate the interfacial contact of the Schottky characteristics for the (0002) plane and the quasi-ohmic behavior for the ( ̅1102) plane. Regarding the piezotronic properties under applied forces, the Schottky barrier height increases in conjunction with the deflection force with high current density at large biases because of tunneling. The strain-induced piezopotential can thus tune the transport process of the charge carriers inside the InN nanorod over a larger range than in ZnO. The quantized surface electron accumulation layer is demonstrated to modulate the piezopotential-dependent carrier transport at the metal/InN interfaces and become an important factor in the design of InN-based piezotronic devices and nanogenerators.


Assuntos
Índio/química , Nanotecnologia/instrumentação , Nanotubos/química , Cristalização , Transporte de Elétrons , Tamanho da Partícula , Propriedades de Superfície
10.
J Hazard Mater ; 203-204: 158-68, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22195520

RESUMO

This investigates the concentrations of Mn, Zn, Cr, Cu, and Pb ambient air in total suspended particulates (TSPs) and dry deposition. The ratios of the calculated to measured dry deposition fluxes of ambient-air Mn, Zn, Cr, Cu and Pb at five characteristic sampling sites from 2009 to 2010 were determined using two dry deposition models. Experimental results demonstrate that the mean concentrations of metallic elements in TSPs and dry deposition were highest at the Quan-xing (industrial) sampling site, which is surrounded by various industrial factories and is in a severely polluted area. The mean seasonal concentrations of metallic elements in TSPs were highest in the winter and fall at all five sites. The analytical concentrations of metallic elements in fall and winter at these five sites were elevated in low winds. The Baklanov model yielded more accurate predictions concerning the dry deposition of metallic elements in ambient air when the sizes of the deposited particles were <5.6 µm, and the Noll and Fang model yielded better predictions when the sizes of the particles were >5.6 µm.


Assuntos
Poluentes Atmosféricos/química , Metais/química , Tamanho da Partícula , Controle de Qualidade , Taiwan
11.
Environ Monit Assess ; 184(2): 729-40, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21448627

RESUMO

The main purpose for this study is to observe the seasonal and monthly variations for arsenic (As) in total suspended particulates (TSP) concentration and dry deposition at five characteristic sampling sites during the years 2009 and 2010 in central Taiwan. The results show that the highest and lowest monthly average As concentrations in TSP occurred in January and May at Bei-shi (suburban/coastal) and Quan-xing (industrial) sampling sites. In addition, the results show that the highest and lowest monthly average As dry deposition occurred in October and May at Chang-hua (downtown) and Gao-mei (wetland) sampling sites. This study reflected that the mean highest As concentrations in TSP and mean highest As dry deposition occurred at Quan-xing (industrial). However, the mean lowest As concentrations in TSP and mean lowest As dry deposition also occurred at Gao-mei (wetland). Regarding seasonal variation, the results show that the As average seasonal concentration order in TSP was winter > spring > fall > summer, respectively, at Chang-hua (downtown) and He-mei (residential) sampling sites. Finally, the order of As average seasonal dry deposition was fall > winter > spring > summer, respectively, at Chang-hua (downtown), He-mei (residential), and Gao-mei (wetland) sampling sites.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Arsênio/análise , Atmosfera/química , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Taiwan
12.
ACS Nano ; 5(8): 6707-13, 2011 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-21774517

RESUMO

We studied the dependence of the output of the piezoelectric nanogenerator (NG) on the inclining orientation of the ZnO nanowire arrays (NWAs). The oblique-aligned NWAs were grown by combing a modified oblique-angle sputtering technique for preparing the seed layer and hydrothermal growth. The piezoelectric output of the NWAs was studied by scanning the tip of an atomic force microscope along four different directions in reference to the inclining direction of the NWs. The statistical outputs were analyzed in reference to the theoretically calculated piezopotential distribution in the NWs. Our study provides in-depth understanding about the performance of NGs.

13.
Environ Monit Assess ; 181(1-4): 273-89, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21161583

RESUMO

The main purpose for this study is to observe the seasonal and month variations for particulates-bound mercury Hg(p) in total suspended particulates (TSP) concentration, dry deposition at five characteristic sampling sites during years of 2009-2010 in central Taiwan. The results show that the highest and lowest monthly average particulates-bound mercury Hg(p) concentrations in TSP were occurred in Dec. and Oct. at Gao-mei (wetland), Chang-hua (downtown) and He-mei (residential) sampling site. In addition, the results show that the highest and lowest monthly average particulates-bound mercury Hg(p) dry deposition was occurred in Feb. and Oct. at Quan-xing (industrial) sampling site. This study reflected that the mean highest particulates-bound mercury Hg(p) concentrations in TSP and mean highest particulates-bound mercury Hg(p) dry deposition were occurred at Gao-mei (wetland) and Quan-xing (industrial). However, the mean lowest particulates-bound mercury Hg(p) concentrations in TSP and mean lowest particulates-bound mercury Hg(p) dry deposition were also occurred at Gao-mei (wetland). Regarding seasonal variation, the order of mean-particulates-bound mercury Hg(p) concentrations in TSP in winter and spring were Gao-mei (wetland) > Quan-xing (industrial) > Bei-shi (suburban/coastal) > Chang-hua (downtown) > He-mei (residential). Finally, the order of mean-particulates-bound mercury Hg(p) dry deposition in fall, spring and summer were Quan-xing (industrial) > Bei-shi (suburban/coastal) > Chang-hua (downtown) > He-mei (residential) > Gao-mei (wetland).


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Mercúrio/análise , Material Particulado/análise , Poluição do Ar/estatística & dados numéricos , Atmosfera/química , Tamanho da Partícula , Estações do Ano , Taiwan
14.
Nanotechnology ; 21(50): 505703, 2010 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-21098939

RESUMO

Gallium implantation of ZnO by a focused-ion beam is used to create a mask for ZnO dry etching with hydrogen. Effects of Ga(+) fluence on the etch stop properties and the associated mechanisms are investigated. The fluence of 2.8 × 10(16) cm(-2) is determined to be optimum to render the best mask quality. While lower fluences would cause less etching selectivity, higher fluences would cause erosion of the surface and particles to be precipitated on the surface after H(2) treatment at high temperature. In contrast to the commonly adopted gallium oxide formation on Si, transmission electron microscopy analysis reveals that, for the fluences ≤ 2.8 × 10(16) cm(-2), Ga(+) ions are incorporated as dopants into ZnO without any second phases or precipitates, indicating the Ga-doped ZnO layer behaves as a mask for H(2) etching due to the higher electronegativity of Ga(+) towards oxygen. However, for the fluences ≥ 4.6 × 10(16) cm(-2), the surface particles are responsible for the etch stop and are identified as ZnGa(2)O(4). We finally demonstrate a complicated pattern of 'NCKU' on ZnO by using this technique. The study not only helps clarify the related mechanisms, but also suggests a feasible extension of the etch stop process that can be applied to more functional material.

15.
J Hazard Mater ; 180(1-3): 115-21, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20435413

RESUMO

The main purpose of this study is to observe the concentration variations for metallic elements in the atmosphere in Asian countries during 2000-2007. These metallic elements typically generated by human activities are directly or indirectly detrimental to human health. The results show that the highest average metallic elements concentrations of Fe, Cu, Zn and Mn in total suspended particles (TSP) were in China, while the lowest average concentrations were in Japan. For metallic elements Cr and Ni, the highest average concentrations in Japan. The highest average concentrations for metallic element Pb were in China while the lowest average concentrations were in Hong-Kong. These analytical results show that the highest average metallic elements concentrations of Pb, Mn, Cr and Ni in PM(10) occurred in Hong-Kong while the lowest average concentrations were in India. In addition, the lowest average concentrations for Zn and Fe occurred in India. These analytical results demonstrate that the highest average concentrations of Pb in PM(2.5) occurred in Hong-Kong while the lowest average concentration was in Japan. The lowest average concentrations for Cu, Mn, Cr and Ni, the average lowest concentrations occurred in Bangladesh. Taiwan had the lowest average concentrations of Cu and Ni among all Asian countries studied during 2000-2007.


Assuntos
Poluentes Atmosféricos/análise , Metais/análise , China , Japão
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