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Urban dust is an important medium of potential toxic metal (PTM) pollution that affects human health and the urban ecosystems. A total of 374 fugitive dust samples were collected in Nanjing, a fast-developing city in southern China, including six sub-types of dust (residential district, commercial district, industrial district, traffic district, cultural and educational district, green land). Chemical analysis of eighteen metal elements by inductively coupled plasma mass spectrometry was carried out to establish the sub-type sources profiles of fine particles for fugitive dust. The results show that these metals (Cu, Zn, Se, Sr, Mo, Cd, Sb, and Pb) are mainly from anthropogenic sources and present a high degree of pollution; Mn, As, and Ba are moderately affected by human activities and present a significant degree of pollution; Ni, Co, Cr, Tl, V, Be, and Ti mainly originate from natural sources and present significant, moderate and minimal degrees of pollution. For the dust types from different functional areas, the differences of enrichment factor (EF) values were relatively small. Metals were highly concentrated in dust from residential, cultural and educational district, which had high density population and would pose higher health risk. In all types of dust, the metals rich in crust (Ti, Mn, Ba, Sr) and the metals (Cu, Zn, Pb) closely connected with city activities were the main components. Factor analysis revealed that there were six main sources of metals in dust collected from Nanjing: industrial activity, building decoration, soil dust, metal smelting, traffic emissions, and brake abrasion. Generally, noncarcinogenic and carcinogenic health risks of metals found in dust are rarely found for children and adults based on health risk assessments. However, the noncarcinogenic risk of Pb in commercial districts for children should be noted because its hazard quotient was higher than the safety threshold level. For the accumulative health risk of eighteen metals, the noncarcinogenic risk values of dust from six functional areas for children were all over the threshold (1.0), whereas below 1.0 for adults. The difference between children and adults was relatively obvious. All accumulative risk values of carcinogenic metals did not exceed the carcinogenic risk threshold of 1 × 10−4, which suggested that no risk prevention measures were needed.

Perfect absorbers with high quality factors (Q-factors) are of great practical significance for optical filtering and sensing. Moreover, tunable multiwavelength absorbers provide a multitude of possibilities for realizing multispectral light intensity manipulation and optical switches. In this study, we demonstrate the use of vanadium dioxide (VO2)-assisted metasurfaces for tunable dual-band and high-quality-factor perfect absorption in the mid-infrared region. In addition, we discuss the potential applications of these metasurfaces in reflective intensity manipulation and optical switching. The Q-factors of the dual-band perfect absorption in the proposed metasurfaces are greater than 1000, which can be attributed to the low radiative loss induced by the guided-mode resonances and low intrinsic loss from the constituent materials. By utilizing the insulator–metal transition in VO2, we further proved that a continuous tuning of the reflectance with a large modulation depth (31.8 dB) can be realized in the designed metasurface accompanied by a dual-channel switching effect. The proposed VO2-assisted metasurfaces have potential applications in dynamic and multifunctional optical devices, such as tunable multiband filters, mid-infrared biochemical sensors, optical switches, and optical modulators.

A numerical investigation of lateral migration of a neutrally buoyant particle in Couette flow with two different thermal boundary conditions is performed using a lattice Boltzmann method coupled with a discrete element method. The effects of the channel Reynolds number (Re), the Grashof number (Gr) as well as the particle size on the migration behaviour are explored in detail. It was found that when both the top and bottom walls are hot, the equilibrium positions are located below the centerline for all the particle sizes studied, which can be well characterised using a dimensionless force ratio determined by the Richardson number (Ri=Gr/Re2) and the confinement ratio. With the increase of the force ratio, the equilibrium position moves towards the bottom wall. On the other hand, when the top wall is cold and the bottom wall is hot, a transition of the equilibrium position is observed, which switches from below the centerline to above the centerline as the particle size is increased above a certain threshold. It is discovered that the critical Reynolds number at transition can be well described by a power law of the confinement ratio. Furthermore, it is also found that the variation of the equilibrium positions above the centerline is governed by a new dimensionless parameter Gr/Re for a fixed particle size, which is attributed to the finite size effect.

Objective: High-sensitivity cardiac troponins I (hs-cTnI) has been endorsed as a standard biomarker for diagnosis of acute myocardial infarction (AMI) and can provide information for risk stratification. Our study aimed to develop a quantum-dot-labeled magnetic immunoassay for the hs-cTnI detection. Methods: We developed a novel immunomagnetic microparticle and quantum dots-based sandwich assay (QM-cTnI) that employs digital recording of fluorescence. Immunomagnetic microparticle conjugated with two monoantibodies was used as capture antibody, and two biotinylated monoantibodies were used as detection antibody, then quantum dots conjugated streptavidin served as a fluorescence bioprobe and the signal was recorded by the luminescence spectrometer. Results: Hs-cTnI was quantifiable in serum within one hour in the QM-cTnI assay which has a detection limit of 0.047 ng/mL and the effective measuring range was 0–40 ng/mL. The intra-assay and interassay coefficients of variation were 8.56% and 8.92% at 0.2 ng/mL, 5.83% and 7.66% at 4 ng/mL, and 6.21% and 8.76% at 20 ng/mL, respectively. All of the recovery rates were within the range of 98.11–101.89% and the average recovery rate was 99.69%. This assay performed well compared with FDA-approved SIEMENS ADVIA Centaur XP immunoassay system by 104 patient serum samples (R2 = 0.9951). High-concentration interferents (bilirubin, triglycerides, and hemoglobin) did not influence the test results indicating good specificity of the MQ-cTnI assay. Conclusion: Our results demonstrated that hs-cTnI sandwich assay with the immunomagnetic microparticle and quantum dots-based multi-mAb approach is a sensitive, accurate, and quantitative method for the detection of disease biomarkers. Keywords: High-sensitivity, Cardiac troponins I, Assay, Immunomagnetic microparticle, Quantum dots, Fluorescence

Chirality is a nearly ubiquitous natural phenomenon. Its minute presence in most naturally occurring materials makes it incredibly difficult to detect. Recent advances in metasurfaces indicate that they exhibit devisable chirality in novel forms; this finding offers an effective opening for studying chirality and its features in such nanostructures. These metasurfaces display vast possibilities for highly sensitive chirality discrimination in biological and chemical systems. Here, we show that two-layer metasurfaces based on twisted nanorods can generate giant spin-selective transmission and support engineered chirality in the near-infrared region. Two designed metasurfaces with opposite spin-selective transmission are proposed for treatment as enantiomers and can be used widely for spin selection and enhanced chiral sensing. Specifically, we demonstrate that the chirality in these proposed metasurfaces can be adjusted effectively by simply changing the orientation angle between the twisted nanorods. Our results offer simple and straightforward rules for chirality engineering in metasurfaces and suggest intriguing possibilities for the applications of such metasurfaces in spin optics and chiral sensing.

Manipulation of polarization state is of great fundamental importance and plays a crucial role in modern photonic applications such as optical communication, imaging, and sensing. Metamaterials and metasurfaces have attracted increasing interest in this area because they facilitate designer optical response through engineering the composite subwavelength structures. Here we propose a general methods of designing half-wave plate and demonstrate in the near-infrared wavelength range an optically thin plasmonic metasurface half-wave plates that rotate the polarization direction of the linearly polarized incident light with a high degree of linear polarization. The half-wave plate functionality is realized through arranging the orientation of the nanoantennas to form an appropriate spatial distribution profile, which behave exactly as in classical half-wave plates but over in a wavelength-independent way.

Binary adhesive packings of microspheres with certain size ratios are investigated via a 3-D discrete-element method specially developed with adhesive contact mechanics. We found a novel phenomenon that the packing fraction of the binary adhesive mixtures decreases monotonically with the increase of the amount of small components. It was further divulged that this behavior results from the competition between a geometrical filling effect and an adhesion effect. The positive geometrical filling effect only depends on the size ratio, while a dimensionless adhesion parameter Ad is used to characterize the negative adhesion effect, which comes to its maximum at Ad ≈ 10. Structural properties, including contact network, partial coordination number, radial distribution function, and angular distribution function, are analyzed to give a better understanding of such adhesive binary packings. © 2017 American Institute of Chemical Engineers AIChE J, 63: 4296–4306, 2017

With a novel 3D discrete-element method specially developed with adhesive contact mechanics, random loose packings of uniform spherical micron-sized particles are fully investigated. The results show that large velocity, large size or weak adhesion can produce a relatively dense packing when other parameters are fixed, and these combined effects can be characterized by a dimensionless adhesion parameter ( $Ad=\omega/2\rho_pU^2_0R$). Four regimes are identified based on the value of $Ad$: RCP regime with $Ad20$. Force distribution of these adhesive loose packings follows $P(f)\sim f^\theta$ for small forces and $P(f)\sim \exp^{-\beta f}$ for big forces, respectively, which shares a similar form with that in packings without adhesion but results in distinct exponents of $\theta=0.879$, $\beta=0.839$. A local mechanical equilibrium analysis shows that adhesion enhances both sliding and rolling resistance so that fewer neighbours are needed to satisfy the force and torque balance., Comment: 12 pages, 10 figures

Spin-selective manipulation of optical waves is widely utilized in various optical techniques and plays a key role in modern nanophotonics. While numerous efficient approaches have been applied in metasurfaces to realize spin-selective manipulation of optical waves, the implementation of giant spin-selective asymmetric transmission remains a challenge. Here, we propose an all-dielectric metasurface to realize giant tri-band spin-selective asymmetric transmission in the near infrared regime. The proposed giant spin-selective asymmetric transmission is attributed to the excitation of overlapping multipolar resonances in the dielectric elliptic cylinders, which can be well manipulated by changing the structure parameters. This research demonstrates the great potential of all-dielectric metasurfaces for spin-selective transmission manipulation, which provide helpful insights and intriguing possibilities for applications in information optics, quantum optics, optical sensing, and imaging.

We investigate photovoltaic effect of atomtronics induced by artificial gauge field in four optical potentials. Effective magnetic flux gives rise to polarization of atom occupation probability which creates current of atomtronics. The relation between atomic current and magnetic flux behaves like the current-phase property in Josephson junction. The photovoltaic cell is well defined by the atomic opened system which have effective voltage and two different poles that correspond to two internal states of atomtronics. The atom flow is controllable by changing the direction of incident light and other system parameters. Detection of the atomic current intensity is available through light emission optical spectrum in experiments., 6 pages, 5 figures

Background: China has implemented numerous pilots to shift its hospital payment mechanism from the traditional retrospective cost-based system to prospective diagnosis-related-group (DRG) -based system. This study investigated the impact of the DRG payment reform with global budget in Zhongshan, China. Methods: A total of 2895 patients diagnosed with acute myocardial infarction (AMI) were selected from local two largest tertiary hospitals, among which 727 were discharged prior to the payment reform and 2168 afterwards. Difference-in-difference (DID) regression models were used to evaluate the policy effects on patients’ percutaneous coronary intervention (PCI) use, hospital expenditures, in-hospital mortality, and readmission rates within 30 days after discharge. Results: Patients’ PCI use and hospital expenditures increased quickly after the payment reform. With patients with no local insurance scheme as reference, PCI use for local insured patients decreased significantly by 4.55 percent (95 percent confidence interval [CI]: 0.23, 0.72), meanwhile the total hospital expenses decreased significantly by US$986.10 (b=-0.15, P=0.0037) after reform. No changes were observed with patients’ hospital mortality and readmission rates in our study. Conclusion: The innovative DRG-based payment reform in Zhongshan suggested a positive effect on AMI patient’s cost containment but negative effect on encouraging resource use. It had no impacts on patients’ care quality. Cost shifting consequence from the insured to the uninsured was observed. More evidence of the impacts of the DRG-based payment in China’s health scenario is needed before it is generalized nationwide

Objectives Admission rates have increased in China, despite the fact that accessibility to primary care is improving. Hospital care could be cost-inefficient, and little is currently known about the appropriateness of admissions to tertiary hospitals in China. This study aims to measure the extent of inappropriate admissions in the cardiology and orthopedics departments of a tertiary hospital in Shanghai, to explore the factors associated with inappropriateness for each department, and to identify the causes of inappropriate admissions. Methods The records of inpatients discharged on randomly sampled two days each week during March 2013 to February 2014 from the two departments were extracted. Two reviewers were recruited to assess the records according to the Chinese version of the Appropriateness Evaluation Protocol (C-AEP). Demographic, socio-economic, and other admissions-related variables were collected. Logistic regression analysis was adopted to determine the associated factors of inappropriateness. Results 35.0% (N = 120) of the 343 admissions and 38.7% (N = 179) of the 463 admissions of the cardiology and orthopedics departments were not justified by the C-AEP, respectively. Age (OR = 0.717), self-pay (OR = 3.752), admission via outpatient sector (OR = 5.332), and readmission (OR = 2.501) were identified as factors affecting the appropriateness of admissions in the cardiology department. Age (OR = 0.930), self-pay (OR = 2.597), admission during 12:00–17:59 (OR = 3.211), and admission via outpatient sector (OR = 7.060) were determined to be associated with appropriateness of admission in the orthopedics department. The main reason for inappropriateness was premature admission for both departments. Conclusions The magnitude of inappropriate admissions was considerable in the departments. To improve appropriateness, the results suggest that further interventions should be focused on both external and internal factors.

The impaction of a single fly ash particle with a powdery layer consisting of uniform fine particles is numerically studied by means of the discrete element method. The influences of the incident velocity and the packed particle size on the microstructure of the powdery layer as well as the impact crater are systematically investigated. It is found out that with the increase of the impact velocity, the incident particle undergoes a transition from a complete sticking regime to a stable rebounding regime, where almost all the incident particles rebound after impaction. The critical incident velocity to reach the stable rebounding regime increases with the increase of the packed particle size. Furthermore, the evolution of the microstructure of the particle layer is evaluated quantitatively in terms of the local coordination number and void fraction, of which the variations increase with the decrease of the packed particle size, and increase quasi-linearly with the increase of the incident velocity. In addition, the normalized size of the impact crater is found to follow a 1/5 power law of the normalized impact energy. However, with the same incident velocity, the normalized crater size seems to be identical for different packed particle sizes.

Three-dimensional (3D) positioning with the correction of imaging aberrations in the photonic platform remains challenging. Here, we combine techniques from nanophotonics and machine vision to significantly improve the imaging and positioning performance. We use a titanium dioxide metalens array operating in the visible region to realize multipole imaging and introduce a cross-correlation-based gradient descent algorithm to analyze the intensity distribution in the image plane. This corrects the monochromatic aberrations to improve the imaging quality. Analysis of the two-dimensional aberration-corrected information in the image plane enables the 3D coordinates of the object to be determined with a measured relative accuracy of 0.60%–1.31%. We also demonstrate the effectiveness of the metalens array for arbitrary incident polarization states. Our approach is single-shot, compact, aberration-corrected, polarization-insensitive, and paves the way for future integrated photonic robotic vision systems and intelligent sensing platforms that are feasible on the submillimeter scale, such as face recognition, autonomous vehicles, microrobots, and wearable intelligent devices.

BACKGROUND This study investigated how miR-21 expression is reflected in acute myocardial infarction and explored the role of miR-21 and the PTEN/VEGF signaling pathway in cardiac microvascular endothelial cells. MATERIAL AND METHODS We used an in vivo LAD rat model to simulate acute myocardial infarction. MiR-21 mimics and miR-21 inhibitors were injected and transfected into model rats in order to alter miR-21 expression. Cardiac functions were evaluated using echocardiographic measurement, ELISA, and Masson staining. In addition, lenti-PTEN and VEGF siRNA were transfected into CMEC cells using standard procedures for assessing the effect of PTEN and VEGE on cell proliferation, apoptosis, and angiogenesis. MiR-21, PTEN, and VEGF expressions were examined by RT-PCR and Western blot. The relationship between miR-21 and PTEN was determined by the luciferase activity assay. RESULTS We demonstrated that miR-21 bonded with the 3'-UTR of PTEN and suppressed PTEN expressions. Established models significantly induced cardiac infarct volume and endothelial injury marker expressions as well as miR-21 and PTEN expressions (P0.05). MiR-21 mimics exhibited significantly protective effects since they down-regulated both infarction size and injury marker expressions by increasing VEGF expression and inhibiting PTEN expression (P0.05). In addition, results from in vitro research show that lenti-PTEN and VEGF siRNA can notably antagonize the effect of miR-21 on cell proliferation, apoptosis, and angiogenesis (P0.05). CONCLUSIONS MiR-21 exerts protective effects on endothelial injury through the PTEN/VEGF pathway after acute myocardial infarction.

Pharmacogenetics has provided compelling evidence towards the influence of gene polymorphisms on warfarin therapies. This study aimed to determine the impact of CYP2C19 gene polymorphism on warfarin maintenance doses in patients with non-valvular atrial fibrillation for the progress in overcoming obstacles facing warfarin pharmacogenetics.In this study, we utilized polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to investigate the distribution of CYP2C19*2 and *3 gene polymorphism in patients with NVAF. In order to exclude the interference of basic indexes, we compared the association between different genotypes and warfarin maintenance doses. And the comparisons among extensive metabolizer, intermediate metabolizer and poor metabolizer were performed.CYP2C19 mutation accounted for 88.07% of in total NVAF patients, which was 7.38 times of CYP2C19*1/*1 (11.93%). No significant association was observed between different genotypes and basic indexes. The warfarin maintenance dose of patients with CYP2C19*1/*1 was significantly higher than those with other five genotypes (all P0.05). Besides, the warfarin maintenance doses of patients with CYP2C19*1/*2 and *1/*3 were remarkably higher than those with *2/*2 and *2/*3 (P0.05). The warfarin maintenance doses of patients with extensive metabolizer were dramatically higher than those with intermediate metabolizer and poor metabolizer (both P0.05), and also the patients with intermediate metabolizer had higher warfarin maintenance doses than those with poor metabolizer (P0.05).CYP2C19 gene polymorphism can affect maintenance dose of warfarin, with the amount of warfarin dose ranked among different genotypes as follow: CYP2C19*2/*2, CYP2C19*2/*3 and CYP2C19*3/*3CYP2C19*1/*2 and CYP2C19*1*CYP2C19*1/*1.

A simple and fast analytical method for determination of eleven Polyfluorinated Compounds (PFCs) in source water was developed in the present work. The water sample was prepared without filtered through microfiltration membrane and 500mL of source water was enriched by the solid phase extraction (SPE). The targent compounds were analyzed by ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The optimized analytical method was validated in terms of recovery, precision and method detection limits (MDLs). The recovery values after correction with the corresponding labeled standard were between 97.3 and 113.0% for samples spiked at 5ng/L, 10ng/L and 20ng/L. All PFCs showed good linearity and the linear correlation coefficient was over 0.99. The precisions were 1.0-9.0% (n=6). As the result of the enrichment, the MDL values ranged from 0.03 to 1.9ng/L and were enough for analysis of the trace levels of PFCs in the Taihu Lake. The method was further validated in determining the source water and the results showed that PFHxS, PFHxA, PFOA and PFOS were the primary PFCs in Taihu Lake which might be different from the other researches. The method can be used for determination of PFCs in water with a stable recovery, good reproducibility, low detection limit, less solvent consumption, time saving and labor saving. To our knowledge, this is the first method that describes the effect of the filter membrane on the determination of PFCs in water which might acquire more accurate concentration of PFCs in Taihu Lake.

Functional carbon materials have aroused much attention owing to their applications in cellular imaging and sensing. In this paper, we use a hydrothermal approach to prepare luminescent sodium citrate carbon dots (CDs) using glutathione (GSH) as the surface capping reagent. The effects of feed ratio, reaction temperature and reaction time on the luminescent behavior of CDs are investigated. Subsequently, as-prepared CDs are characterized by UV-vis, photoluminescence, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscope (TEM). The luminescent CDs exhibit good stability in the presence of various ions or photo irradiation. Furthermore, the luminescence of the CDs is reversible upon the pH cycling between pH=4 and 6. In addition, the emission intensity of CDs decreases gradually with increasing the concentration of silver nanoparticles (AgNPs) and a linear relationship between the logarithm of emission intensity and the concentration of AgNPs is observed within the investigated concentration ranging from 0 to 40 μmol•L−1. The detection limit is 0.9 μmol•L−1 in terms of signal-to-noise ratio of 3. More importantly, the sensor can be successfully applied to the detection of AgNPs in real lake water, urine of human, Hep-2 cells, E. Coli and Salmonella bacteria, which offers a promising platform for environmental and biological sensing applications.

Highly red luminescent gold nanoclusters (AuNCs) have been prepared at physiological temperature by using glutathione (GSH) as a stabilizing and capping agent in aqueous media. The resultant AuNCs have been characterized by photoluminescence and X-ray photoelectron spectroscopy, transmission electron microscopy and FTIR. The AuNCs exhibit red fluorescence with a quantum yield of 3.1 %, and fluorescence is strongly quenched by copper(II) ion due to aggregation. This finding is exploited in a fluorometric assay for Cu(II) that has a 2.8 nM detection limit. The method was applied to the determination of Cu(II) ion in (spiked) mineral water and Tai Lake water. In addition, the AuNCs display a strongly temperature-dependent emission that can be used for optical determination of temperature in the 0 to 60 °C range. We finally show that the AuNCs are viable nanomaterials for (a) plain imaging of Hep-2 cells by laser scanning confocal microscopy, and for (b) intracellular imaging of Cu(II) and of temperature in Hep-2 cells and E. coli.

Water-soluble and highly fluorescent copper nanoclusters (Cu NCs) using glutathione as a stabilizing agent have been prepared. The as-prepared Cu NCs have an average diameter of about 2.2 nm and are shown to be viable fluorescent probes for the determination of Cr(VI) ions owing to the inner filter effect of Cr(VI) ions. The Cu NCs have been characterized in terms of photoluminescence excitation spectroscopy, photoluminescence spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy. Furthermore, the nanosensor exhibits high sensitivity to Cr(VI) ions with a detection limit of 1.5 μM and has been demonstrated for the determination of Cr(VI) ions in real water samples including tap water, mineral water, and Taihu lake water. In addition, the as-prepared NCs could be used as versatile nanothermometry devices in cellular and in vivo temperature sensing based on obvious temperature dependence on the fluorescence emission intensity, which changes obviously over the physiological temperature range (279–323 K).

It is known that vascular smooth muscle cell (VSMC) proliferation and migration leads to intimal hyperplasia in cases of atherosclerosis and restenosis. In the present study, we investigated the effects of kindlin-2 on VSMC proliferation, migration and intimal hyperplasia, and the underlying mechanisms. The left common carotid artery of Sprague‑Dawley rats were subjected to balloon injury in order to induce intimal hyperplasia, and then transfected with kindlin-2 small interfering RNA (siRNA) lentivirus or negative control siRNA lentivirus. We noted that the degree of intimal hyperplasia 4 weeks after balloon injury was significantly reduced in arteries transfected with kindlin-2 siRNA lentivirus (P

Realizing arbitrary manipulation of optical waves, which still remains a challenge, plays a key role in the implementation of optical devices with on-demand functionalities. However, it is hard to independently manipulate multiple dimensions of optical waves because the optical dimensions are basically associated with each other when adjusting the optical response of the devices. Here, the concise design principle of a chiral mirror is utilized to realize the full-dimensional independent manipulation of circular-polarized waves. By simply changing three structural variables of the chiral mirror, the proposed design principle can arbitrarily and independently empower the spin-selective manipulation of amplitude, phase, and operation wavelength of circular-polarized waves with a large modulation depth. This approach provides a simple solution for the realization of spin-selective full-dimensional manipulation of optical waves and shows ample application possibilities in the areas of optical encryption, imaging, and detection.

The impact of formal care (co-paid by long term care (LTC) insurance) on informal care is critical to the improvement and promotion of public policy. We conducted an interview-based survey to examine how the use of formal care impacts the use of informal care in Shanghai, which was one of China&rsquo, s first long-term insurance pilots in 2016. In addition to total informal care time, the following four types of informal care were considered: (1) household activities of daily living (HDL) tasks, (2) activities of daily living (ADL) tasks, (3) instrumental activities of daily living (IADL) tasks, and (4) supervision tasks. Of the 407 families, an average of 12.36 h (SD = 6.70) of informal care was crowded out each week. Among them, ADL tasks, HDL tasks, and supervision tasks were reduced an average of 4.60 (SD = 3.59), 5.50 (SD = 3.38), and 2.10 h (SD = 3.06) per week, respectively. Each additional hour of formal care reduced 0.473 h of informal care. Care recipients&rsquo, gender and health status were also determined to be associated with crowding out hours of informal care. These findings can be utilized as empirical evidence for decision-makers to consider the scope of funding for formal care, and this study provides comparable results to developing countries and regions.

Traditional optical lenses and the corresponding imaging systems, which are based on the optical paths when light propagates inside the bulky media, usually suffer from the bulky size, Abbe-Rayleigh diffraction restricted resolution, and limited responses to different kinds of incident light. Recently, the burgeoning development of metasurfaces comprised of artificial micro- or nano-structures at the subwavelength scale has drawn more and more attentions of the scientific community due to the intriguing abilities such as efficient light–matter interactions and multi-dimensional manipulation of optical waves, which provide profound potentials to realize functional metalens with an ultrahigh numerical aperture (NA) and with super-resolution focal spots on a compact size. Here, the research motivations, the broad outline and the recent advances of planar diffractive metalens are summarized, including the principles of metalens design, the basic components of metalens, and the development of metalens systems. Various approaches to remove the focusing aberrations are presented, which is the essential condition to realize metalens objectives and microscopy. Different types of novel metalenses are revealed, such as label-free sub-resolution metalens, nonlinear metalens, artificial intelligence-aided metalens, multifunctional metalens and reconfigurable metalens. Challenges and future goals are also presented at the end the review.

Introducing a reduced particle stiffness in discrete element method (DEM) allows for bigger time steps and therefore fewer total iterations in a simulation. Although this approach works well for dry non-adhesive particles, it has been shown that for fine particles with adhesion, system behaviors are drastically sensitive to the particle stiffness. Besides, a simple and applicable principle to set the parameters in adhesive DEM is also lacking. To solve these two problems, we first propose a fast DEM based on scaling laws to reduce particle Young’s modulus, surface energy and to modify rolling and sliding resistances simultaneously in the framework of Johnson-Kendall-Roberts (JKR)-based contact theory. A novel inversion method is then presented to help users to quickly determine the damping coefficient, particle stiffness and surface energy to reproduce a prescribed experimental result. After validating this inversion method, we apply the fast adhesive DEM to packing problems of microparticles. Measures of packing fraction, averaged coordination number and distributions of local packing fraction and contact number of each particle are in good agreement with results simulated using original value of particle properties. The new method should be helpful to accelerate DEM simulations for systems associated with aggregates or agglomerates.

In this paper, we consider a Gross-Pitaevskii (GP) equation with a time-dependent nonlinearity and a spatiotemporal complex linear term which describes the dynamics of matter-wave solitons in Bose-Einstein condensates (BECs) with time-dependent interatomic interactions in a parabolic potential in the presence of feeding or loss of atoms. We establish the integrability conditions under which analytical solutions describing the modulational instability and the propagation of both bright and dark solitary waves on a continuous wave background are obtained. The obtained integrability conditions also appear as the conditions under which the solitary waves of the BECs can be managed by controlling the functional gain or loss parameter. For specific BECs, the dynamics of bright and dark solitons are investigated analytically through the found exact solutions of the GP equation. Our results show that under the integrability conditions, the gain or loss parameter of the GP equation can be used to manage the motion of both bright and dark solitons. We show that for BECs with loss (gain) of atoms, the bright and dark solitons during their propagation have a compression (broadening) in their width. Furthermore, under a safe range of parameters and under the integrability conditions, it is possible to squeeze a bright soliton of BECs with loss of atoms into the assumed peak matter density, which can provide an experimental tool for investigating the range of validity of the 1D GP equation. Our results also reveal that under the conditions of the solitary wave management, neither the injection or the ejection of atoms from the condensate affects the soliton peak during its propagation.

Metasurfaces, 2D artificial arrays of subwavelength elements, have attracted great interest from the optical scientific community in recent years because they provide versatile possibilities for the manipulation of optical waves and promise an effective way for miniaturization and integration of optical devices. In the past decade, the main efforts were focused on the realization of single-dimensional (amplitude, frequency, polarization, or phase) manipulation of optical waves. Compared to the metasurfaces with single-dimensional manipulation, metasurfaces with multidimensional manipulation of optical waves show significant advantages in many practical application areas, such as optical holograms, sub-diffraction imaging, and the design of integrated multifunctional optical devices. Nowadays, with the rapid development of nanofabrication techniques, the research of metasurfaces has been inevitably developed from single-dimensional manipulation toward multidimensional manipulation of optical waves, which greatly boosts the application of metasurfaces and further paves the way for arbitrary design of optical devices. Herein, the recent advances in metasurfaces are briefly reviewed and classified from the viewpoint of different dimensional manipulations of optical waves. Single-dimensional manipulation and 2D manipulation of optical waves with metasurfaces are discussed systematically. In conclusion, an outlook and perspectives on the challenges and future prospects in these rapidly growing research areas are provided.

A modified lossless nonlinear Noguchi transmission network with second-neighbor interactions is considered. In the semidiscrete limit, we apply the reductive perturbation method and show that the dynamics of modulated waves propagating through the network are governed by an NLS equation with linear external potential. Classes of exact solitonic solutions of this network equation are derived, proving possible transmission of both bright and dark solitonlike pulses through the network. The effects of both the coupling second-neighbor parameter L_{3} and the strength λ of the linear potential on the dynamics of modulated waves through the network are investigated. One of the main results of our work is that with the introduction of the second neighbors in the network, two solitary signals, either two bright solitary signals or one bright and one dark solitary signal, may simultaneously propagate at the same frequency through the network.

Moreover, the development of a feasible metadevice design that has the ability to dynamically tune the light polarization state has attracted enormous interest. Such metadevices can be employed for realizing not only the polarization encoding but also polarization-division multiplexing (PDM), which is a crucial technique that can signifi cantly increase the transmission capacity of a single physical channel. [ 34 ] The traditional technique for realizing PDM requires a complex optical system and cumbersome volume. Therefore, a metadevice-based polarization modulator offers a new approach for simplifying the optical process and miniaturizing the required volume. Although metasurfaces can transform light polarization, the change of polarization-control characteristic requires variation of the size, shape, and material properties of the structure. Hence, the dynamical manipulation of the polarization state using a metasurface is still challenging. In this work, we propose a metadevice by integrating a single layer of graphene with an anisotropic metasurface, which can dynamically modulate the polarization state of light with wide tunable range in MIR wavelengths. By switching gate voltage applied on the graphene among three different values, the incident linearly polarized (LP) light can be dynamically converted into left circularly polarized (LCP) light, right circularly polarized (RCP) light, or linearly cross-polarized light in the refl ection direction by the proposed metadevice. A continuous polarization evolution from LCP to RCP light can be achieved as the gate voltage gradually increases. In addition, two mutually perpendicular LP light beams and an elliptically polarized (EP) light beam can also be generated in the refl ection direction by the proposed metadevice under EP light illumination. Based on these polarization-control characteristics, the proposed metadevice can realize polarization encoding and the PDM technique. The process of multiplexing and demultiplexing in the PDM technique can be accomplished by metadevices with a more simple approach and in a more compact space than traditional PDM techniques. The new degrees of freedom enabled by the metadevice facilitate the arbitrary manipulation of light polarization states and will profoundly affect a wide range of modern optical communication devices. Control of the light polarization state is an important area of research for metasurfaces. The anisotropy of plasmonic metasurfaces plays a dominant role in manipulating the light polarization state. The different optical responses along two orthogonal principal axes of the nanostructures result in different amplitude attenuation and phase retardation of the Optical Polarization Encoding Using Graphene-Loaded Plasmonic Metasurfaces

Purpose – The purpose of this paper is to explore the effect of surface roughness characterized by fractal geometry on squeeze film damping characteristics in damper of the linear rolling guide, which has not been studied so far. Design/methodology/approach – The stochastic model of film thickness between rail and damper is established by using the two-variable Weierstrass–Mandelbrot function defining multi-scale and self-affinity properties of the rough surface topography. The stochastically averaged Reynolds equation is solved by using the variables separation method to further derive the film pressure distribution, the damping coefficient, the damping force and squeeze film time. The effect of surface roughness on squeeze film damping characteristics of the damper is analyzed and discussed through simulation. Findings – By comparing cases of the rough surface for different fractal parameters and the smooth surface, it is shown that for the isotropic roughness structure, the presence of surface roughness of the damper decreases the squeeze film damping characteristics. It is found that roughness effect on the damping coefficient is associated with the film thickness. In addition, the vibration amplitude effect is negligible for the damper of the linear rolling guide. Originality/value – To investigate the random surface roughness effect, the rough surface topography of damper of the linear rolling guide is characterized by using the fractal method instead of the traditional mathematical statistics method.

Metasurfaces, which are capable of generating structure and wavelength dependent phase shift, have emerged as promising means for controlling the wavefront of electromagnetic waves. Finding new ways to realize broadband frequency response as well as maintaining high conversion efficiency still requires research efforts. For the design of plasmonic metasurfaces, graphene represents an attractive alternative to metals due to its strong field confinement and versatile tunability. Here, a novel metasurface based on graphene is proposed to control the wavefront of light. Dynamically tunable anomalous refraction composed of periodically patterned graphene nanocrosses for circularly polarized waves is achieved in the infrared regime. Broadband properties of anomalous refraction are demonstrated by investigating different frequencies and incident angles. Moreover, the anomalous conversion efficiency can be dynamically tuned and remain as high in a broadband frequency range by varying the Fermi energy without reoptimizing the nanostructures. This work may offer a further step in the development of a tunable wavefront controlling device.

We propose a new method of controlling signal light intensity by changing the polarization direction of pump light that is incident on a phase-gradient metasurface. Theoretical analyses and simulations demonstrate that, when the incident angles for signal and pump light sources conform to a certain relationship, the anomalous refraction of the pump light superposes with the signal light. The intensity of the signal light can be fully tuned across a broadband range by varying the polarization direction of the pump light. Our methods will contribute to the development of promising techniques to be used in photonics devices such as amplitude modulators and photoswitches.

Manipulation of light phase and amplitude by plasmonic metasurfaces has immensely promising applications in optical imaging, information processing, communications, and quantum optics. However, the controllability of efficiency and bandwidth is relatively low for the single-layer metasurfaces. Here, a high efficiency and broadband circularly polarized (CP) beam deflector based on multirod single-layer metasurfaces is presented. Each unit can be regarded as an imperfect polarizer, and the phase and amplitude induced by the mirror effect can be easily controlled. Owing to the plasmonic hybridization, the high efficiency and broadband characteristics of the proposed metasurfaces are theoretically and experimentally demonstrated. Meanwhile, an easy way to determine the polarization degree of the incident light based on Poincare sphere is also proved by the multirod metasurfaces. Our work provides a simple alternative way to enhance the efficiency of CP anomalous light and thus has robust applications in nanophotonics and nanooptics.

We present the underlying theory, the design specifications, and the simulated demonstration of a high performance broadband asymmetric polarization conversion composed of an L-shaped gold particle and a gold nanoan- tenna array for the near-infrared regime. It can transform linearly polarized light to its cross polarization in the trans- mission mode for one propagation direction and efficiently reflect the light for the opposite propagation direction. The broadband asymmetric polarization conversion can be attributed to the polarization-dependent reflection of the nanoantenna array, which enhances the polarization con- version efficiency of the L-shaped particle and makes it asymmetric and devisable. This work offers a further step in the development of a high efficiency broadband optical activity device.

Objective: To explore the clinical significance of heparin-binding epidermal growth factor-like growth factor (HB-EGF), interleukin-18 (IL-18), and interleukin-10 (IL-10) in restenosis after percutaneous coronary intervention (PCI). Methods: A total of 198 patients with acute coronary syndrome underwent coronary drug-eluting stent implantation and were divided into the restenosis group and non-restenosis group on the basis of second coronary angiography. Biological parameters and HB-EGF, IL-18, and IL-10 levels were measured. Patients in the restenosis group were further divided into 3 subgroups according to Gensini score: group A (Gensini score of 20 but 40). Results: Compared with the non-restenosis group, HB-EGF and IL-18 levels were significantly higher but serum IL-10 levels were significantly lower in the restenosis group. Furthermore, HB-EGF levels increased with the Gensini score among the 3 subgroups. Spearman’s correlation analysis showed that HB-EGF levels were associated with IL-18 levels and the number of diseased vessels. Multivariate logistic regression analysis showed that diabetes, HB-EGF, and IL-18 were risk factors for restenosis [odds ratio with 95% confidence interval: 3.902 (1.188-4.415), 2.185 (1.103-4.014), and 2.079 (1.208-4.027), respectively]. Conclusion: The present study has demonstrated that HB-EGF may be used to evaluate the severity of restenosis and coronary artery lesion and that inflammatory responses may be involved in the process of restenosis.

Highly red luminescent and water-soluble Ag2S nanoclusters (NCs) are synthesized using glutathione as a stabilizing and capping agent. The as-prepared NCs have been characterized in terms of photoluminescence excitation spectrum, photoluminescence spectrum, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The NCs are shown to be viable fluorescent probes for the determination of Cu2+ ions due to aggregation-induced quenching of fluorescence. Furthermore, the nanosensor exhibits high sensitivity to Cu2+ ions with a detection limit of 2.5 nmol L−1 and has been demonstrated for determination of Cu2+ ions in real water samples including tap water, mineral water, and Taihu lake water. In addition, the as-prepared NCs could be used as versatile nanothermometry devices in cellular and in in vivo temperature sensing based on obvious temperature dependence on the logarithm of fluorescence emission intensity, which changes obviously over the physiological temperature range (6–50 °C).

We present a plasmonic lens with a dynamically tunable focal length in the mid-infrared region that is composed of gold film with annular slits and embedded vanadium dioxide (VO2) nanorings. When illuminated with radially polarized light, a perfect circularly symmetric focusing spot can be dynamically tuned between the near and far fields by decreasing temperature, and it can always be focused beyond the diffraction limit. A physical model of the tunable plasmonic lens is also proposed to explain the mechanisms by which the focal length is dynamically tuned. The field enhancement and the focal length can be further tuned by adding concentric annular slits and VO2 nanorings, respectively, while keeping the focusing spot size small. This provides a further step in the development of a perfect tunable plasmonic lens.

Preclinical Research The abnormal migration and proliferation of vascular smooth muscle cells (VSMCs) plays a pivotal role in the development of neointimal hyperplasia after vascular injury. Nobiletin, a citrus bioflavonoid, exhibits anti-inflammatory and anti-oxidative activities. The present study evalutaed whether nobiletin could inhibit platelet-derived growth factor (PDGF)-BB- stimulated VSMC proliferation and migration and decrease neointimal hyperplasia in a rat carotid artery injury model. Cultured VSMCs from rat thoracic aortas were treated with nobiletin before being stimulated with 20 ng/ml PDGF-BB, and rats were subjected to carotid artery injury. Nobiletin inhibited PDGF-BB-induced VSMC proliferation and migration, attenuated reactive oxygen species (ROS) production and reduced phosphorylation of ERK1/2 and the expression of nuclear NF-κB p65 in PDGF-BB-stimulated VSMCs. Nobiletin decreased the intima area and the ratio of neointima to media in balloon-injured rat carotid arteries. Serum levels of TNF-α and IL-6 in nobiletin-treated rats were decreased. These results indicated that nobiletin could be a potential protective agent for the prevention and treatment of restenosis after angioplasty.

The contact stiffness of joint surface plays a significant role in the overall static and dynamic characteristics of mechanical systems. When considering joint interfaces with two rough surfaces, the traditional model based on Hertz contact theory between a sphere and a plane is difficult to use, especially for increasingly complex engineering surfaces. In order to overcome the weakness, here we propose a new contact stiffness model in view of the influence of domain extension factor between two rough surfaces. We study the deformation mechanism and the critical contact parameters. Subsequently, we analyze evolution of the elastic-plastic contact involving three distinct stages ranged from complete elastic through elastic-plastic to fully plastic deformation. Our fractal model is more universal than the traditional model based on some strict assumptions which simplify the contact of two rough surfaces to a rough surface and a rigid plane. In fact, the traditional model could be regarded as a special case in our new model. Simulations show that non-dimensional normal contact stiffness increases with dimensionless contact total load under the mechanism of elastic-plastic transition when the fractal dimension is between 1.1 to 1.5. The results indicate that contact stiffness of our fractal model is appropriate and the theoretical contact stiffness is consistent with the experiment data. DOI: http://dx.doi.org/10.5755/j01.mech.23.5.19356

Biqi capsule is a well-known traditional Chinese medicine (TCM) formula that has been widely applied for the clinical treatment of such diseases as rheumatoid arthritis, scapulohumeral periarthritis, and cervical spondylopathy. However, there is concern regarding the toxicity of Biqi capsule due to its active ingredients, strychnine and brucine. To investigate the toxicokinetics of strychnine and brucine after the oral administration of Biqi capsule to rats, a sensitive and simple rapid-resolution liquid chromatography/tandem mass spectrometry (RRLC-MS/MS) method was developed to determine the levels of strychnine and brucine in rat plasma. Chromatographic separation was performed on a CAPCELL PAK C18 MG II (3.0 μm, 2.0×35 mm) column by gradient elution with acetonitrile and 0.2% formic acid as the mobile phase. The method was validated over the range of 0.25 to 250 ng/mL for strychnine and 0.025 to 25 ng/mL for brucine. The intra- and inter-day accuracies of strychnine and brucine in rat plasma were 100.3%-106.6% and 90.75%-106.1% respectively, and the precisions were within 14.2%. The established method was successfully applied to the toxicokinetic study of strychnine and brucine after single and multiple oral administration of Biqi capsule to male and female rats at 0.4-, 0.8-, and 1.6-g/kg doses. The results showed different toxicokinetic characteristics in the different groups.