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Abstract Purpose This study aimed to verify that aerosolization ocular surface microorganisms (AOSMs) accumulated during non-contact tonometry (NCT) measurements. Methods A total of 508 participants (740 eyes) were enrolled in the study. In Experiment 1, before NCT was performed on each eye, the air was disinfected, and environment air control samples were collected via Air ideal® 3P (Bio Merieux). During NCT measurements, microbial aerosol samples were collected once from each eye. In Experiment 2, we collected initial blank control samples and then repeated Experiment 1. Finally, in Experiment 3, after the background microbial aerosol investigation, we cumulatively sampled AOSMs from each 10 participants then culture once, without any interventions to interrupt the accumulation. The collected samples were incubated and identified using matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Results Pathogenic Aerococcus viridans and other microorganisms from human eyes can spread and accumulate in the air during NCT measurements. The species and quantity of AOSMs produced by NCT measurements can demonstrate an accumulation effect. Conclusion AOSMs generated during NCT measurements are highly likely to spread and accumulate in the air, thereby may increase the risk of exposure to and transmission of bio-aerosols.

In remote sensing problems, broadband scattering investigation becomes increasingly important than ever before. The scattering characteristic changes significantly with the variation of range. Thus, the conventional evaluation method becomes invalid in many situations. Meanwhile, an efficient method for the simulation of electromagnetic wave propagation in electrically large remote sensing problem is also an urgently demanding. In order to alleviate such problems, an alternative Crank-Nicolson Direct-Splitting algorithm is proposed in open regions. To infinite extension of the computational domain, convolutional perfectly match layer with higher order formulation is proposed not only to further enhance the absorption at low-frequency band but also to decrease the reflections during the entire time domain simulation. Efficient method is proposed for scattering characteristics evaluation which ranges from near-field to far-field. Radar remote sensing Problems including ground penetrating radar and early warning radar are introduced to demonstrate the effectiveness of the algorithm. Through the results, it can be concluded that the proposed algorithm shows considerable performance in the simulation of remote sensing problems.

Abstract Purpose To compare the effect of traditional conjunctival sac swab sampling (A) with aerosolization ocular surface microorganism sampling (B),a novel microbial sampling method, in detecting ocular microbial infection. Methods The study included 61 participants (122 eyes) enrolled at the Eye Hospital, Wenzhou Medical University from December, 2021 to March, 2023. Each eye of the participants underwent sampling first with method A then B.Before aerosolization sampling, the air environment was disinfected and sampled as blank air control sample. Subsequently, the air pulses impinging the ocular surface causes dehiscence of the tear film covering the ocular surface and aerosols are formed.The microorganisms from the ocular surface attach to the aerosols generated as aerosolization ocular surface microorganism and be sampled as subject sample by bio-aerosol sampler.The samples were collected and incubated at 25℃ for 3–5 days and 37℃ for 24–48 h.The colonies were counted and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Results The accuracy in Group B was higher than that in Group A (45.8% vs. 38.3%, P = 0.289). There was a slight level of agreement between the results from both the sampling methods (k = 0.031, P = 0.730). The sensitivity in Group B was higher than that in Group A (57.1% vs. 35.7%, P = 0.453). The specificity results in Group B was higher than that in Group A (44.3% vs. 38.7%, P = 0.480). There were 12 and 37 types of microbes detected in Groups A and B, respectively. Conclusions Compared with traditional swab sampling, the novel aerosolization sampling method shows higher accuracy and more comprehensive detection of microbes; however, it cannot completely replace swab sampling. The novel method can be a novel conducive strategy and supplement swab sampling to auxiliary diagnose ocular surface infection.

Context Morinda officinalis F.C. How. (MO) (Rubiaceae) can strengthen bone function.Objective To examine the functional mechanism and effect of MO polysaccharides (MOPs) in rats with glucocorticoid-induced osteoporosis (GIOP).Materials and methods Rats with GIOP were treated with 5, 15 or 45 mL/kg of MOP [n = 15 for each dose, intraperitoneal (i.p.) injection every other day for 8 weeks]. The body weight of rats and histomorphology of bone tissues were examined. Bone marrow mesenchymal stem cells (BMSCs)-derived exosomes (Exo) were collected and identified. Bone marrow-derived macrophages (BMMs) were induced to differentiate into osteoclasts and treated with BMSC-Exo for in vitro studies.Results MOP reduced the body weight (5, 15, or 45 mg/kg MOP vs. phosphate-buffered saline: 8%, 15% and 25%, p

H _2 O _2 is part of Europa’s water-ice radiolytic cycle and a potential source of oxidants to Europa’s subsurface ocean. However, factors controlling the concentration of this critical surface species remain unclear. Though laboratory experiments suggest that Europa’s H _2 O _2 should be concentrated in the coldest, most ice-rich regions toward the poles, Keck adaptive optics observations have shown the strongest H _2 O _2 signatures in comparatively warm, salt-bearing terrain at low latitudes. As a result, it was suggested that the local non-ice composition of these terrains—particularly hypothesized enrichments of CO _2 —may be a more dominant control on H _2 O _2 than temperature or water-ice abundance. Here we use observations of Europa from the NASA Infrared Telescope Facility, Keck Observatory, and JWST to disentangle the potential effects of temperature and composition. In order to isolate the effect of temperature on Europa’s H _2 O _2 , we use the ground-based observations to assess its response to temperature changes over timescales associated with Europa’s daily eclipse and diurnal cycle. We use JWST Cycle 1 data to look for any geographic correlation between Europa’s H _2 O _2 and CO _2 . Changes in Europa’s 3.5 μ m H _2 O _2 absorption band both from pre- to post-eclipse and across a local day suggest minimal effects of the local temperature on these timescales. In contrast, the JWST observations show a strong positive correlation between Europa’s H _2 O _2 and CO _2 bands, supporting the previously suggested possibility that the presence of CO _2 in the ice may enhance H _2 O _2 concentrations via electron scavenging.

For the simulation of gyrotropic plasma structure with fine geometry details along a single direction in open regions, the hybrid implicit-explicit (HIE) algorithm with improved absorbing boundary condition is modified based on the finite-difference time-domain (FDTD) algorithm. More precisely, incorporating the perfectly matched layer (PML) formulation, the higher order concept and the HIE procedure, the proposed implementation shows its significant superiority in terms of efficiency, accuracy and absorption. To simulate the unique anisotropic characteristic inside the gyrotropic plasma regions, the bilinear transform (BT) method is employed during the calculation. The effectiveness can be further demonstrated theoretically and numerically. Through the results, it can be concluded that the proposed scheme exhibits remarkable behaviors in the gyrotropic plasma open region problems. It can not only obtain considerable accuracy compared with the theoretical solution but also receive better absorption and efficiency compared with the published work. In addition, the results also indicate that the proposed scheme can maintain the stability of the algorithm with dissatisfaction of the Courant-Friedrichs-Levy condition between time step and mesh size.

By incorporating higher order formulation with perfectly matched layer (PML) implementation, unconditionally stable computationally efficient locally one-dimensional (LOD) algorithm with improved absorption is proposed for simulating ground penetrating radar and its open region problems in finite-difference time-domain (FDTD) algorithm. To take advantages of these methods, the proposed implementation shows characteristics of maintaining considerable accuracy, enhancing computational efficiency and improving the entire absorption. These above-mentioned advantages are illustrated through the ground penetrating radar related problem in open regions. It can be concluded from the calculation results that the proposal shows advantages of higher order formulation, PML implementation and LOD procedure which are efficient in remarkable accuracy, considerable efficiency and improved absorption with increment of CFLNs. Meanwhile, the simulation results also indicate that the proposal is an unconditionally stable procedure with the dissatisfaction of Courant-Friedrichs-Levy stability condition.

Low-pressure discharge causes air ionization resulting in performance degeneration or failure for the satellite sensors in outer space. Here, a one-step Crank-Nicolson Direct-Splitting (CNDS) algorithm is proposed to evaluate the electrical behavior of satellite sensors under the low-pressure discharge circumstance. To be more specific, the CNDS algorithm is proposed in the Lorentz medium, which can accurately analyze the ionized air and generated plasma. Higher order perfectly matched layer (PML) is modified in the Lorentz medium to efficiently terminate the unbounded lattice. It can be concluded that the proposed algorithm shows entire considerable performance in the low-pressure discharge evaluation. The proposed PML formulation behaviors enhanced absorbing performance compared with the existing algorithm. Through the experiments, it can be observed that the low-pressure discharge phenomenon causes performance variation, which shows a significant influence on the satellite sensors. Meanwhile, results show considerable agreement between the simulation and experiment results which indicates the effectiveness of the algorithm.

Abstract Objective To evaluate the clinical effect of the second puncture and injection technique during a percutaneous vertebroplasty (PVP) procedure. Methods Patients treated with a second puncture and injection (group A) or a single puncture and injection (group B) during PVP at our institution during 2010–2017 were reviewed. Vertebral height loss, visual analogue scale (VAS) score, Oswestry disability index (ODI), adjacent vertebral fractures, and cement leakage were compared between the groups. Results A total of 193 patients were enrolled (86 cases in group A, 107 cases in group B). The follow-up period was 15.64 (12–20) months. The loss of anterior (group A 0.01 ± 0.03; group B 0.14 ± 0.17) and middle (group A 0.13 ± 0.12; group B 0.16 ± 0.11) vertebral height in group B was significantly higher than that in group A (P < 0.05). The VAS score and ODI were also significantly higher in group B than in group A at the final follow-up; the VAS score and ODI in group B were 1.65 ± 0.70 and 14.50 ± 4.16, respectively, and those in group A were 1.00 ± 0.74 and 12.81 ± 4.02, respectively (P < 0.05). Three patients in group A and two in group B experienced adjacent vertebral fractures. Regarding mild, moderate, and severe cement leakage, there were 25 (29%), 5 (5%), and 0 cases, respectively, in group A and 28 (26%), 3 (2.8%), and 1 (0.009%) case, respectively, in group B (P > 0.05). Conclusions The second puncture and injection technique may effectively increase the dispersion of cement, thus preventing recompression of the cemented vertebral body, and it does not increase the risk of cement leakage or adjacent vertebral fracture.

A large number of sensors work in the narrow bandpass circumstance. Meanwhile, some of them hold fine details merely along one and two dimensions. In order to efficiently simulate these sensors and devices, the one-step leapfrog hybrid implicit-explicit (HIE) algorithm with the complex envelope (CE) method and absorbing boundary condition is proposed in the narrow bandpass circumstance. To be more precise, absorbing boundary condition is implemented by the higher order convolutional perfectly matched layer (CPML) formulation to further enhance the absorption during the entire simulation. Numerical examples and their experiments are carried out to further illustrate the effectiveness of the proposed algorithm. The results show considerable agreement with the experiment and theory resolution. The relationship between the time step and mesh size can break the Courant–Friedrichs–Levy condition which indicates the physical size/selection mesh size. Such a condition indicates that the proposed algorithm behaviors are considerably accurate due to the rational choice in discretized mesh. It also shows decrement in simulation duration and memory consumption compared with the other algorithms. In addition, absorption performance can be improved by employing the proposed higher order CPML algorithm during the whole simulation.

Most terahertz (THz) radar systems can only work in the near-field region, because the THz source power is limited and the size of the target scattered near field is up to tens of kilometers. Such conditions will result in the conventional radar range equation being unsuitable. Therefore, the near-field radar cross section (RCS) formula is given according to the numerical simulation on different targets. By modifying the parameters in the near field, including the gain of radar antennas and the RCS of targets, the generalized radar range equation is proposed. The THz radar working efficiency in the whole range and the simulation of the near-field RCS simulation model were employed to validate its effectiveness. Through comparison with the radar range equation, it can be concluded that the calculation results of the proposed equation are smaller in the near field, and the outcomes in the far field are identical. The proposed generalized radar range equation can be applied to the whole radiation area including the near field and the far field. Furthermore, more complicated real targets are calculated according to the generalized radar range equation and it can be extended from the submillimeter wave band to a much wider band range. Finally, the near-field radar theory is established, which shows its potential application to the radar cross section estimation in the extremely high frequency and fine design of THz radar systems.

This study investigates the characteristics of electromagnetic scattering in complex electromagnetic environments by using half-space theory with multiple radiators. We identify differences in the characteristics of the target scatterings between single and multiple radiators of a radar in the half-space through a comparison between the half-space and free space and single and multiple radiators. Numerical examples featuring a prismatic model of the perfect electronic conductor and the cruise missile model are used to show that the distribution of surface current density is affected by both the half-space and multiple radiators. The variation in surface current density changes the characteristics of scattering, and such a condition is reflected in the patterns of radiation. To further examine the influence of this phenomenon on multiple radiators, factors such as the amplitude of the electric field, phase difference, and mode of polarization were considered. The results show that the characteristics of scattering are significantly influenced by a number of factors.

According to the two-dimensional aperture principle, directivity and gain are expected to be proportional to the aperture area of an antenna or antenna array. Our simulations and measurements of an end-fire radiation antenna array overturn this conventional wisdom. The gain of an end-fire antenna array is found to be much higher than that calculated by the two-dimensional aperture principle. We introduce a length component into the two-dimensional aperture principle and propose a three-dimensional aperture principle. A four-element end-fire antenna array is designed and measured to verify the correctness of this new principle. The three-dimensional aperture principle opens a pathway to novel types of aperture utilization.

By incorporating the higher-order concept with the perfectly matched later (PML) scheme, unconditionally stable approximate Crank–Nicolson algorithm is proposed for plasma simulation in open region problems. More precisely, the proposed implementation is based on the CN Direct-Splitting (CNDS) procedure for the finite-difference time-domain (FDTD) unmagnetized plasma simulation. The unmagnetized plasma can be regarded as frequency-dependent media which can be calculated by the piecewise linear recursive convolution (PLRC) method. The proposed implementation shows the advantages of higher-order concept, CNDS procedure, and PLRC method in terms of improved absorbing performance, enhanced computational efficiency, and outstanding calculation accuracy. Numerical examples are introduced to indicate the effectiveness and efficiency. It can be concluded from results that the proposed scheme shows considerable efficiency, accuracy, absorption, and unconditional stability.

In order to investigate the influence of multi-radiators, active scattering characteristics, which can be reflected by the active radar cross section (ARCS), are investigated by incorporating the multi-radiators with the radar-radiator. The proposed implementation takes advantage of the ARCS concept in terms of considerable accuracy and close to reality especially in the complex electromagnetic environment. The metal sphere model is analyzed to demonstrate the effectiveness of the proposed implementation. Several procedures are employed during the investigation. The ARCS of the metal sphere model is compared with its radar cross section with a single radar-radiator. The frequency characteristic of the ARCS for a metal sphere model with multi-radiators is calculated. The changes in the ARCS with different phases, field intensities, field polarization directions are given. An example is given to illustrate the change in the maximum detection range caused by multi-radiators. Through the results, it can be concluded that the active scattering characteristics of the metal sphere model can be significantly influenced by the multi-radiators.

Several models on the circadian effect have been applied to indoor circadian lighting design, but applications in road lighting have not yet been clarified. Based on existing models and circadian research, we examined equivalent melanopic lux (EML), circadian light (CLA), and circadian stimulus (CS) representing the circadian effect and the S/P ratio representing the mesopic vision effect, among a dataset of light sources at photopic adaptation illuminance values of 1, 3, 10, 30, and 100 lx. The results show that the S/P ratio correlates with EML and CS (or CLA) much stronger than it correlates with color temperature. The EMLs of light sources are below 50 EML in mesopic vision, and the CSs of most light sources are below or around the threshold value of 0.05. We conclude that the circadian effect is not a significant issue in mesopic vision under most conditions and that optimization for mesopic efficiency is still a good strategy. There are quite a few light sources that may achieve both ideal mesopic efficiency and low CS. This work clarifies the circadian effect and mesopic vision effect performance of light sources in mesopic vision and will help guide choosing suitable light sources and optimization strategies for road lighting.

In this work, we investigated the luminous and melanopic efficiency of the radiation (LER/MER) performances of phosphor-converted LEDs (PC LEDs) with tunable spectral characteristics, namely peak wavelength, full width at half maximum (FWHM), and emission intensity. We constructed theoretical PC LED spectra based on the characteristics extracted from the database of IES TM-30-15, analyzed the relations between LER/MER and different spectral characteristics, and proposed spectral composition strategies at various correlated color temperatures (CCTs). Results showed that both MER and LER are linear with the FWHM of phosphor within the peak wavelength range in practical use, but the change in values by tuning emission intensity varies with spectral compositions. Hence, different spectral characteristics should be considered comprehensively. We further explored the trade-off between luminous and melanopic efficiency. Lowering the FWHM of phosphor and the intensity distribution of the blue LED can obtain higher LER and low circadian effect at lower CCT. As CCT increases, considering color rendering and the increase in the blue intensity distribution, besides reducing FWHM, tuning the peak wavelength close to the peak wavelength of V(λ) helps to reduce the circadian effect. These investigations provide optimization strategies for ideal melanopic and luminous performance of PC LED light sources.

In order to analyze the scattering properties in multi-radiator problems, the active radar cross section (ARCS) concept is proposed under complex electromagnetic (EM) environments. The corresponding calculation methods and formulation are proposed by incorporating the monostatic radar cross section (RCS) concept with external disturbances. By introducing the phase characteristics into the ARCS concept, the coherent problems can be accurately solved. Through analyzing the external disturbance and the radar waves by employing the finite element method, the coherent and the incoherent characteristics of the external disturbance can be simulated in complex structures. Numerical examples and an experiment are carried out to further demonstrate the effectiveness of the proposed ARCS concept. The results demonstrate that the proposed ARCS concept obtains better universality compared with the existing incoherent multi-radiator formulation. Meanwhile, the ARCS can be identical with the solution which is obtained by the single radar wave. Compared with the existing incoherent methods for external disturbances calculations, the proposed ARCS concept is more rational. Through the experiment, the effectiveness of the calculation method and formulation is further demonstrated and validated.

We fabricated graphene-thermopolyurethane (G-TPU) flexible conductive film by a blending method and systematically investigated the electrical, thermal and self-healing properties of the G-TPU flexible conductive film by infrared light and electricity. The experimental results demonstrate that the G-TPU composite films have good conductivity and thermal conductivity in the appropriate mass content of graphene in the composite film. The composite films have the good electro-thermal and infrared light thermal response performances and electro-thermal response performance is closely related to the mass content of graphene in the composite film, but the infrared light thermal response performance is not. The scratch on the composite film can be completely healed, using electricity or infrared light. The healing efficiency of the composite film healed using infrared light is higher than that of using the electricity, while the healing time of the composite film is shorter. Regardless of the self-healing method, the temperature of the self-healing is a very important factor. The self-healing conductive composite film still exhibits a good conductivity.