Qiang Li

Zhejiang University, Hang-hsien, Zhejiang Sheng, China

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Publications (126)324.21 Total impact

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    ABSTRACT: Background Tuberculosis (TB) patients in China encounter heavy financial burdens throughout the course of their treatment and it is unclear how China’s health insurance systems affect the alleviation of this burden under the integrated approach. This study aimed to measure reimbursement for TB services under the New Cooperative Medical Scheme (NCMS) in rural China and to evaluate changes in catastrophic health expenditure (CHE) caused by the reimbursement policies. Methods Reimbursement data were obtained from routine data systems for the NCMS in Yichang (YC) and Hanzhong (HZ). 1884 TB inpatients reimbursed by NCMS from 2010 to 2012 were included. Household surveys were conducted. A total of 494 TB patients under the NCMS were selected in this paper. 12 Focus Group Discussions (FGDs) were held. We measured the impact of the NCMS by counterfactual analysis, which analyzed the financial burden alleviation. Equity was assessed by Concentration Index (CI), and disaggregated by project sites. Results TB inpatients were reimbursed with an effective reimbursement rate of 57.3 %. Average out-of-pocket (OOP) payments for outpatient and inpatient services after diagnosis were 1413 yuan and 430 yuan, and 3572 yuan and 3013 yuan in YC and HZ, respectively. The reimbursement level for TB outpatient care after diagnosis was very low due to a limited outpatient quota. TB patients in HZ incurred higher effective reimbursement rates, but the incidence of CHE remained higher. The reduction of CHE incidence after the NCMS showed no difference statistically (P > 0.05). The severity of CHE was alleviated slightly. CIs after reimbursement were all below zero and their absolute values were higher than those before reimbursement. Conclusions Low reimbursement for TB patients could lead to heavy financial burden. Poor TB patients incurred high rates of CHE. The NCMS was found to be a protective factor for CHE, but the impact was modest and the equity of CHE did not improve. The NCMS reimbursement policies should be improved in the future to include a more comprehensive coverage of care. Supplemental programs may be necessary to expand coverage for TB care. Electronic supplementary material The online version of this article (doi:10.1186/s40249-015-0094-5) contains supplementary material, which is available to authorized users.
    No preview · Article · Dec 2016 · Infectious Diseases of Poverty

  • No preview · Article · Dec 2016 · Infectious Diseases of Poverty
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    ABSTRACT: Background Treatment of tuberculosis (TB) in China is partially covered by national programs and health insurance schemes, though TB patients often face considerable medical expenditures. For some, especially those from poorer households, non-medical costs, such as transport, accommodation, and nutritional supplementation may be a substantial additional burden. In this article we aim to evaluate these non-medical costs induced by seeking TB care using data from a large scale cross-sectional survey. Methods A total of 797 TB cases from three cities were randomly selected using a stratified cluster sampling design. Inpatient medical costs, outpatient medical costs, and direct non-medical costs related to TB treatment were collected using in-person interviews by trained interviewers. Mean and median non-medical costs for different sub-groups were calculated and compared using Kruskal-Wallis and Mann–Whitney U tests. Regression analysis was conducted to assess the influence of different patient characteristics on total non-medical cost. Results The median non-medical cost was RMB 1429, with interquartile range RMB 424–2793. The median non-medical costs relating to inpatient treatment, outpatient treatment, and additional nutrition supplementation were RMB 540, 91, and 900, respectively. Of the 797 cases, 20 % reported catastrophic expenditure on non-medical costs. Statistically significant differences were detected between different cities, age groups, geographical locations, inpatient/outpatient care, education levels and family income groups. Conclusions Non-medical costs relating to TB treatment are a serious financial burden for many TB patients. Financial assistance that can limit this burden is urgently needed during the treatment period, especially for the poor. Electronic supplementary material The online version of this article (doi:10.1186/s40249-016-0101-5) contains supplementary material, which is available to authorized users.
    No preview · Article · Dec 2016 · Infectious Diseases of Poverty
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    Yuanqing Yang · Qiang Li · Min Qiu
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    ABSTRACT: Owing to their high capacity and flexibility, broadband wireless communications have been widely employed in radio and microwave regimes, playing indispensable roles in our daily life. Their optical analogs, however, have not been demonstrated at the nanoscale. In this paper, by exploiting plasmonic nanoantennas, we demonstrate the complete design of broadband wireless links and networks in the realm of nanophotonics. With a 100-fold enhancement in power transfer superior to previous designs as well as an ultrawide bandwidth that covers the entire telecommunication wavelength range, such broadband nanolinks and networks are expected to pave the way for future optical integrated nanocircuits.
    Full-text · Article · Jan 2016 · Scientific Reports
  • Jingyi Tian · Qiang Li · Yuanqing Yang · Min Qiu
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    ABSTRACT: All-dielectric nanoantennas have become an emerging branch of optical nanoantennas in recent years, with an outstanding ability to tailor forward and backward unidirectional scattering arising from interference mainly between electric dipoles and magnetic dipoles induced simultaneously inside a nanoparticle. To further control its radiation properties, we demonstrate a silicon stair-like nanoantenna scattering incident near-infrared plane wave off normal due to multipolar interference. The radiation angle can be tailored over a 20-degree range by tuning the geometric parameters of the nanoantenna. A multipolar model till the electric quadrupole is adopted to interpret the interference among one electric dipole, two magnetic dipoles and one electric quadrupole induced inside the nanoantenna. The maximum radiation angle reaches 20° near 1550 nm wavelength. Such stair-like nanoantenna sets a good example for further flexible manipulation of multipolar resonances inside all-dielectric nanoparticles, which is an essential step towards practical application of all-dielectric nanoantennas in the near future.
    No preview · Article · Jan 2016 · Nanoscale
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    ABSTRACT: Two spatially and spectrally resolved narrowband absorbers based on 2D grating nanostructures (polymethylmethacrylate (PMMA) grating and gold grating) on metallic films are designed, fabricated, and characterized. For PMMA grating on a metallic film, the measured absorption bandwidth is 12 nm with a nearly 80% absorption at normal incidence. The transverse electric (TE) localized mode shows a calculated 3.5° angular width. The transverse magnetic (TM) resonant mode supports both a localized mode and a lattice mode. The TM lattice mode shows a calculated angular width of 0.75° and exhibits a large wavelength-angle sensitivity of nearly 15 nm per degree and a large absorption-angle sensitivity of 77.5% per degree. For gold grating on a metallic film, the measured absorption bandwidth is 40 nm with a nearly 70% absorption. Such spatially and spectrally resolved 2D nanostructure arrays with large angle sensitivities have potential applications in angle measurement, thermal emitters, optical filters, and biosensors.
    No preview · Article · Jan 2016 · Advanced Optical Materials
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    ABSTRACT: To evaluate the status of feeding practices and analyze the association between feeding practice and health status among Tibetan infants, a cross-sectional survey of 386 women with children aged under 24 months was conducted in rural areas surrounding Lhasa, Tibet. All participants were selected using simple random sampling and were interviewed face-to-face by trained interviewers. Mothers were interviewed to collect information on their feeding practices. A feeding practices index was created using the rank sum ratio method. Most of the infants had been or were being breastfed at the time of the interview. The feeding practices index was significantly and inversely associated with the prevalence of acute upper respiratory infection, and the odds ratio for the qualified feeding practices index vs. the non-qualified feeding practices index was 0.43 (95% confidence interval: 0.20-0.94). There were no measurable associations observed between acute upper respiratory infection, diarrhea, and the feeding practices index after controlling for selected factors. The method of rank sum ratio provides a flexible way to evaluate feeding practices and is easy to understand. Furthermore, appropriate infant feeding practices might play a protective role in Tibetan infants' health.
    Preview · Article · Dec 2015 · International Journal of Environmental Research and Public Health
  • Hangbo Yang · Min Qiu · Qiang Li
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    ABSTRACT: Leaky plasmon modes (LPMs) in metal nanowires (NWs), which combine the physical characteristic of both “plasmonics” and “leaky radiation”, present distinguished performances in terms of guiding and radiating light. In contrast to traditional light-guiding in metal NWs with one single LPM, multiple LPMs are crucial for advanced uses such as augmenting data transmission channels, enhancing sensing performance, manipulating polarization and converting mode. Here, we demonstrate experimentally the control over multiple LPMs in pentagonal silver NWs. By combining far-field real-space imaging and leakage radiation microscopy, the three typical LPMs with fields mainly concentrating in corners surrounded by air are specifically identified. By manipulating excitation wavelengths and NW diameters, the number of the excited LPMs can be controlled. These findings reveal the physics of LPMs in silver NWs, thereby paving the way towards applying the high-order leaky modes in silver NWs for photonic integrated circuits, nanoscale confinement, plasmonic sensing, QD-nanowire coupling, etc.
    No preview · Article · Dec 2015 · Laser & Photonics Review
  • Weichun Zhang · Qiang Li · Lijun Meng · Ding Zhao · Min Qiu
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    ABSTRACT: Knowledge of temperatures at the nanoscale is essential for studying and controlling the heat-induced local thermal responses. The temperature rise of a heated nanoparticle (NP) near the interface of two kinds of media with different thermal conductivities is numerically investigated. We find that the temperature rise becomes size independent if it is scaled by the temperature rise in the case where the particle-interface distance is zero and the distance is scaled by the equivalent radius of the NP. This universal scaling behavior can be understood with the principle of dimensional homogeneity. An empirical equation is retrieved to predict the actual particle temperature at a given position. Our results may benefit precise control of heat at the nanoscale with applications in plasmonic absorbers, immunotargeted photothermal cancer cell killing, etc. © 2015 Society of Photo-Optical Instrumentation Engineers (SPIE).
    No preview · Article · Oct 2015 · Journal of Nanophotonics
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    ABSTRACT: Au nanoparticles show large third-order nonlinear effect and ultra-fast response. Here a high nonlinear aggregate film based on self-assembled gold nanoparticles is reported and its third-order nonlinear refractive index coefficient is measured by Z-scan experiment. The third-order nonlinear refractive index coefficient of the Au nanoparticle aggregate film (r1 = 9.2�*10-9 cm2/W) is found to be larger than that of an 8-nm-thick sputtered Au film (r2 = 6.5�*10-�9 cm2/W). This large nonlinear effect can be attributed to the strong field enhancement due to localized plasmon resonances between Au nanoparticles. The result shows that the self-assembled Au nanoparticle aggregate film could be a promising candidate as a third-order nonlinear optical material
    Full-text · Article · Oct 2015 · Applied Physics Letters
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    ABSTRACT: Surface plasmon polaritons (SPPs) propagating at metal nanostructures play an important role in breaking the diffraction limit. Chemically synthesized single-crystalline metal nanoplates with atomically flat surfaces provide favorable features compared with traditional polycrystalline metal films. The excitation and propagation of leaky SPPs on micrometer sized (10-20 μm) and thin (30 nm) gold nanoplates are investigated utilizing leakage radiation microscopy. By varying polarization and excitation positions of incident light on apexes of nanoplates, wave-vector (including propagation constant and propagation direction) distributions of leaky SPPs in Fourier planes can be controlled, indicating tunable SPP propagation. These results hold promise for potential development of chemically synthesized single-crystalline metal nanoplates as plasmonic platforms in future applications.
    Full-text · Article · Aug 2015 · Scientific Reports
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    ABSTRACT: A plasmonic trimer composed of three closely packed identical gold nanospheres for manipulating nanoscale temperature distribution is proposed. It is shown that heat can be unevenly distributed among the three particles, creating a high temperature gradient in the nanoscale space despite the strong thermalization effect. Moreover, the difference in temperature increment among the particles is sensitive to the polarization of incident light and can be continuously tuned. The dependence of the achievable temperature difference on the trimer parameters is also investigated. The ability of nanoscale selective heating provides a possible way of remotely manipulating the nanoscale thermally induced physical or chemical processes with unprecedented spatial precision.
    Full-text · Article · Aug 2015 · Plasmonics
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    Yuanqing Yang · Qiang Li · Min Qiu
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    ABSTRACT: Dielectric nanoantennas have generated much interest in recent years owing to their low loss and optically induced electric and magnetic resonances. In this paper, we investigate the coupling between a single emitter and dielectric patch nanoantennas. For the coupled system involving non-spherical structures, analytical Mie theory is no longer applicable. A semi-analytical model is proposed instead to interpret the coupling mechanism and the radiation characteristics of the system. Based on the presented model, we demonstrate that the angular emission of the single emitter can be not only enhanced but also rotated using the dielectric patch nanoantennas.
    Full-text · Article · Jul 2015 · Applied Physics Letters
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    ABSTRACT: Hypertensive patients have more complex health care needs and are more likely to have poorer health-related quality of life than normotensive people. The awareness of hypertension could be related to reduce health-related quality of life. We propose the use of quantile regression to explore more detailed relationships between awareness of hypertension and health-related quality of life. In a cross-sectional, population-based study, 2737 participants (including 1035 hypertensive patients and 1702 normotensive participants) completed the Short-Form Health Survey. A quantile regression model was employed to investigate the association of physical component summary scores and mental component summary scores with awareness of hypertension and to evaluate the associated factors. Patients who were aware of hypertension (N = 554) had lower scores than patients who were unaware of hypertension (N = 481). The median (IQR) of physical component summary scores: 48.20 (13.88) versus 53.27 (10.79), P < 0.01; the mental component summary scores: 50.68 (15.09) versus 51.70 (10.65), P = 0.03. adjusting for covariates, the quantile regression results suggest awareness of hypertension was associated with most physical component summary scores quantiles (P < 0.05 except 10th and 20th quantiles) in which the β-estimates from −2.14 (95% CI: −3.80 to −0.48) to −1.45 (95% CI: −2.42 to −0.47), as the same significant trend with some poorer mental component summary scores quantiles in which the β-estimates from −3.47 (95% CI: −6.65 to −0.39) to −2.18 (95% CI: −4.30 to −0.06). The awareness of hypertension has a greater effect on those with intermediate physical component summary status: the β-estimates were equal to −2.04 (95% CI: −3.51 to −0.57, P < 0.05) at the 40th and decreased further to −1.45 (95% CI: −2.42 to −0.47, P < 0.01) at the 90th quantile. Awareness of hypertension was negatively related to health-related quality of life in hypertensive patients in rural western China, which has a greater effect on mental component summary scores with the poorer status and on physical component summary scores with the intermediate status.
    Preview · Article · Jul 2015 · Medicine
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    ABSTRACT: An uncooled microbolometer based on metamaterial absorbers is investigated. The absorption peak reaches 90%, and the peak wavelength can be tailored from 2.4 to 10.2 $muhbox{m}$ with corresponding bandwidth varying from 0.5 to 1.5 $muhbox{m} $ by tuning the geometric parameters of the absorbers, covering two atmosphere windows (3–5 $muhbox{m}$ and 8–14 $muhbox{m} $) . The thermal distribution in the microbolometer can be adjusted to realize a strong thermal response. In the given situation with a pixel size of 25.07 $muhbox{m} $, the temperature response of the detector reaches 1.3 K. The microbolometer can be potentially used in thermal imaging at selected wavelengths in the mid-infrared and far-infrared regimes.
    Full-text · Article · Jun 2015 · IEEE Photonics Journal
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    ABSTRACT: Objective To assess the status of the vitamin B12 and folate of Chinese women living in northwest China. Methods A population-based cross-sectional study was conducted in 2008 among Chinese women aged 10–49 years living in Shaanxi province of northwest China. A stratified multistage random sampling method was adopted to obtain a sample of 1170 women. The women were interviewed for collection of their background information and their plasma vitamin B12 and folate were measured with the immunoassay method. The status of both vitamins was evaluated and the prevalence of deficiency was estimated. Results The median value of the women was 214.5 pg/mL for vitamin B12 and 4.6 ng/mL for folate. The urban women had a significantly higher vitamin B12 (254.1 vs. 195.9 pg/mL) but lower folate (4.4 vs. 4.7 ng/mL) than rural women. Total prevalence of deficiency was 45.5% (95% CI: 42.6%∼48.4%) for vitamin B12 and 14.7% (95% CI: 12.6%∼16.8%) for folate. About 36% of women presented vitamin B12 deficiency alone, 5.2% belonged to folate deficiency alone and 9.5% was combined deficiency in both vitamins. More than 25% of the women were in marginal vitamin B12 status (200–299 pg/mL) and 60% in marginal status of folate (3–6 ng/mL). About 75.2% of rural women with folate deficiency were deficient in vitamin B12 and 46% for urban women. Quantile regression model found decreasing coefficient of folate status across 73 different quantiles of vitamin B12, which indicated that the women with folate deficiency had lower vitamin B12 significantly compared with those with no deficiency. Conclusions The deficiency of vitamin B12 and folate is still prevalent among the Chinese women in northwest China. Vitamin B12 deficiency could be more serious and the improvement of poor vitamin B12 status should be invoked when practicing the supplementation of folate against the neural tube defects in northwest China.
    Preview · Article · Nov 2014 · PLoS ONE
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    ABSTRACT: A non-complicated, controllable method of metallic nanoparticle fabrication at low operating light power is proposed. The method is based on laser-induced forward transfer, using a metamaterial absorber as the donor to significantly enhance the photothermal effect and reduce the operating light fluence to 35 mJ/cm(2), which is much lower than that in previous works. A large number of metallic nanoparticles can be transferred by one shot of focused nanosecond laser pulses. Transferred nanoparticles exhibit good size uniformity and the sizes are controllable. The optical properties of transferred particles are characterized by dark-field spectroscopy and the experimental results agree with the simulation results.
    Full-text · Article · Aug 2014 · Scientific Reports
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    ABSTRACT: We review here our recent studies on plasmonic enhanced photothermal effects in metallic nanostructure, and the applications of such effects. When light is shined on a prefect metamaterial absorber patterned with e-beam lithography, the gold nanoparticles (NPs) forming the absorber can be either transformed to nano-spherical-domes, or to truncated-octahedral shaped or multi-twined nanocrystals with large crystal grain sizes and flat boundary facets. The evolution of morphology and crystallinity of the gold NPs can be also observed. Evidences clearly show that the surface melting and the coalescence mechanism play a key role on nanocrystals formation. These melted gold nanospheres can even be transferred to another substrate, on which the transferred NPs exhibit excellent size uniformity. The strong photothermal effects can also be utilized to tune silicon photonics waveguides and resonators. It is shown that all-optical photothermal switching of Mach-Zehnder interferometers (MZI), silicon disk resonators, and silicon ring resonators is possible with the help of plasmonic nanoheaters. The switching response time and power consumption are all at reasonably low level.
    Full-text · Conference Paper · Jul 2014
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    ABSTRACT: An ultra-narrow band absorber consisting of continuous silver and alumina films is investigated. Owing to Fabry–Pérot resonance and silver's inherent loss, an ultra-narrow spectral range of light can be entirely trapped in the structure. By varying thicknesses of metallic and dielectric films, absorption peak shifts in visible and near-infrared regions. When two such metal-insulator-metal stacks are cascaded, experimental results show that an ultra-narrow absorption bandwidth of 7 nm is achieved, though theoretical results give that of 2 nm. Features of high-efficiency and ultra-narrow band absorption have huge potential in optical filtering, thermal emitter design, etc.
    Full-text · Article · Jun 2014 · Applied Physics Letters
  • Qiang Li · Weichun Zhang · Ding Zhao · Min Qiu
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    ABSTRACT: Plasmonic nanoparticles (NPs) with photothermal effects can be exploited as efficient heat sources in various applications. Here, the photothermal properties in core-shell structured plasmonic NPs, including metal/silica NP, silica/metal NP, and metal/silica/metal NP, are investigated. Compared with bare metal NPs, the core-shell plasmonic NPs not only exhibit extremely agile tunability in the surface plasmon resonances but also show considerably enhanced photothermal effects in terms of the maximum temperature rise. For metal/silica NPs and metal/silica/metal NPs, the SiO2 shells function as effective thermal-protective layers for enhanced photothermal effect. For silica/metal NPs, the SiO2 core and the metal shell show uniform temperature rise. These findings are essential for applying the core-shell structured plasmonic NPs on photothermal imaging, nanofluidics, etc.
    No preview · Article · Jun 2014 · Plasmonics

Publication Stats

2k Citations
324.21 Total Impact Points

Institutions

  • 2012-2015
    • Zhejiang University
      • • State Key Lab of Modern Optical Instrumentation
      • • Department of Optical Engineering
      Hang-hsien, Zhejiang Sheng, China
  • 2004-2015
    • Shanghai Jiao Tong University
      • • Department of Electronic Engineering
      • • Department of Chemical Engineering (CHE)
      • • Department of Materials Science and Engineering (MSE)
      • • School of Medicine
      Shanghai, Shanghai Shi, China
  • 2005-2013
    • Xi'an Jiaotong University
      • School of Medicine
      Ch’ang-an, Shaanxi, China
    • Chinese Academy of Sciences
      • State Key Laboratory of Molecular Biology
      Peping, Beijing, China
  • 2008-2011
    • KTH Royal Institute of Technology
      • • School of Information and Communication Technology (ICT)
      • • Department of Microelectronics and Applied Physics (MAP)
      Tukholma, Stockholm, Sweden
    • University of Sydney
      Sydney, New South Wales, Australia
  • 2010
    • Tohoku University
      Miyagi, Japan
  • 2004-2007
    • Shanghai University
      • • School of Materials Science and Engineering
      • • Department of Chemical Engineering and Technology
      Shanghai, Shanghai Shi, China
  • 2002-2004
    • Shanghai Institutes for Biological Sciences
      Shanghai, Shanghai Shi, China