Miniaturized Active-Frequency Selective Surfaces for Low-Power Internet of Things Devices.

With the proliferation of smart devices, the Internet of Things (IoT) is rapidly expanding. This study proposes a miniaturized controllable metamaterial with low control voltage for achieving low-power and compact designs in IoT node devices. Operating at a target frequency of 2.4 GHz, the proposed metamaterial requires only a 3.3 V control voltage and occupies approximately one-third of the wavelength in size. Experimental validation demonstrates its excellent reflective control performance, positioning it as an ideal choice for low-power IoT systems, particularly in the context of miniaturized and low-power IoT node applications.

Generation and control of the circle Olver beams: erratum.

We have found an error in our work reported in [Opt. Express31(4), 6241 (2023)10.1364/OE.483433], which we correct in this erratum. The authors apologize for this error and emphasize that none of the results are affected by this error.

Generation and control of the circle Olver beams.

The circle Olver beams (COBs) generated by modulation on the basis of a new type of Olver beam are presented numerically and experimentally. The zeroth order COB is the circle Airy beam. We demonstrate auto-focusing of the COBs with both inward and outward accelerations, where the odd order COBs display auto-defocusing while the even order COBs (ECOBs) tend to focus more abruptly. We also explore the effect of the decay factor and the scaling factor on the beams' focusing properties, such as the initial energy distribution, the focusing position, the focusing intensity and the focusing depth, by using the parity mode. In addition, we verify the self-healing property of the COBs. Finally, we set up an experimental platform to implement particle capture and manipulation with the ECOBs. Our results offer practical applications for particle manipulation, laser processing, etc.

Airy-Talbot plasmon: an accelerating self-imaging surface wave.

In this Letter, a new class of an accelerating self-imaging surface plasmonic wave, the Airy-Talbot plasmon, is introduced for the first time, to the best of our knowledge. Our research shows that such a surface wave propagates at the interface between metal (silver) and a dielectric material (air) and causes a strong interference along curved trajectories, which generates the Talbot effect in the surface. The propagation properties have potential value in nanoscale plasmonic devices. A scheme for generating this novel plasmon theoretically is proposed, and we prove it by finite difference time-domain numerical simulations.

Generation and control of tornado waves by means of ring swallowtail vortex beams.

Tornado waves (ToWs), which refer to a light that accelerates and twists over both the radial and the angular directions, have gained a great deal of interest since the concept was introduced by Brimis et al [Opt. Lett.45, 280 (2020)10.1364/OL.45.000280]. In this paper, we superimpose two pairs of ring swallowtail vortex beams (RSVBs) to generate ToWs and we call them tornado swallowtail waves (ToSWs). Each pair consists of RSVBs while carrying orbital angular momentum of opposite helicity and slightly different with the radius of the main ring of RSVBs. The waves spiral forward and reveal intensity maxima, exhibiting a tornado-like intensity profile during propagation. Meanwhile, the angular acceleration of the ToSWs is illustrated via tracing the angular position of the high-intensity main lobes. It is found that ToSWs present very high values of angular acceleration. Compared with typical tornado waves, ToSWs are more diverse and tunable, giving a new degree of freedom to tailor the propagation dynamics due to the flexibility of the swallowtail diffraction catastrophe. In addition, we confirm such waves experimentally and the results match well with the numerical ones. Also, we demonstrate the ability of optical manipulation of ToSWs for the first time in that they allow for particles not only to be trapped but also to be rotated. Finally, we analyze the poynting vectors and power exchange of ToSWs to demonstrate convincingly the physical mechanism.

Multiple and off-axis optical bottles from the chirped circular Pearcey Gaussian vortex beams.

We introduce a new type of multiple and off-axis optical bottles (OBs) based on the chirped circular Pearcey Gaussian vortex beam. This kind of beam allows the generation of the OBs with a perfect bottle shape through coherent superposition. Also, we show that the number and the position of the OBs can be precisely and flexibly controlled. The experimental results agree well with our numerical simulations, and we observe stable trapping of the mesocarbon microbeads particles by the proposed bottle beam.

Shaping autofocusing Airy beams through the modification of Fourier spectrum.

A new type of Airy beam arisen from the modification of Fourier spectrum is introduced numerically and experimentally. The autofocusing Airy beam (AAB) exhibits the features of off-axis autofocusing and transverse self-accelerating, producing a needle-like focus in the longitudinal direction and a tiny focal spot at the focusing plane. Furthermore, the focusing properties such as focusing position, focal spot size, focusing intensity and depth of focus can be adjusted by modulating parameters of the AAB. Experimental demonstrations of particle trapping and manipulation with the AAB are also presented. The number of trapped particles can be controlled by changing the focal spot size at the autofocusing plane. Our results offer practical applications in particle manipulation, fluorescent imaging technology, laser spectroscopy and so on.

Propagation dynamics of the odd-Pearcey Gaussian beam in a parabolic potential.

In this paper, the propagation properties of the odd-Pearcey Gaussian beam (OPGB) in a parabolic potential are investigated analytically and numerically. Except for the auto-focusing at the focal plane, the OPGB performs a weak off-axis focusing unexpectedly. The focusing distance and the focal intensity can be adjusted by choosing an appropriate parabolic parameter. Also, the Poynting vector of the OPGB is demonstrated. In addition, we investigate the radiation forces of the OPGB and find that the trapping points can be generated during propagation.

Fabrication of InxGa1-xN Nanowires on Tantalum Substrates by Vapor-Liquid-Solid Chemical Vapor Deposition.

InxGa1-xN nanowires (NWs) have drawn great attentions for their applications in optoelectronic and energy conversion devices. Compared to conventional substrates, metal substrates can offer InxGa1-xN NW devices with better thermal conductivity, electric conductivity, and mechanic flexibility. In this article, InxGa1-xN NWs were successfully grown on the surface of a tantalum (Ta) substrate via vapor-liquid-solid chemical vapor deposition (VLS-CVD), as characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), scanning and transmission electron microscope (STEM), and photoluminescence spectroscopy (PL). It was found that the surface pretreatment of Ta and the composition of metallic catalysts played important roles in the formation of NWs. A dimpled nitrided Ta surface combined with a catalyst of nickle is suitable for VLS-CVD growth of the NWs. The obtained InxGa1-xN NWs grew along the [1100] direction with the presence of basal stacking faults and an enriched indium composition of ~3 at.%. The successful VLS-CVD preparation of InxGa1-xN nanowires on Ta substrates could pave the way for the large-scale manufacture of optoelectronic devices in a more cost-effective way.

Development of an In-Patient Satisfaction Questionnaire for the Chinese Population.

BACKGROUND: Patients' satisfaction has been considered as a crucial measurement of health care quality. Our objective was to develop a reliable and practical questionnaire for the assessment of in-patients' satisfaction in Chinese people, and report the current situation of in-patients' satisfaction in the central south area of China through a large-scale cross-sectional study. DESIGN: In order to generate the questionnaire, we reviewed previous studies, interviewed related people, held discussions, refined questionnaire items after the pilot study, and finally conducted a large cross-sectional survey to test the questionnaire. SETTING: This study was conducted in three A-level hospitals in the Hunan province, China. RESULTS: There were 6640 patients in this large-scale survey (another 695 patients in the pilot study). A factor analysis on the data from the pilot study generated four dimensions, namely, doctors' care quality, nurses' care quality, quality of the environment and facilities, and comprehensive quality. The Cronbach's alpha coefficients for each dimension were above 0.7 and the inter-subscale correlation was between 0.72 and 0.83. The overall in-patient satisfaction rate was 89.6%. CONCLUSION: The in-patient satisfaction questionnaire was proved to have optimal internal consistency, reliability, and validity.

A meta-analysis of anterior cruciate ligament reconstruction with autograft compared with nonirradiated allograft.

BACKGROUND: To compare autograft with non-irradiated allograft for reconstruction of anterior cruciate ligament. METHODS: MEDLINE, EMBASE, and Cochrane Library databases, as well as unpublished and ongoing studies were searched through up to 20 July 2013 to identify studies meeting the pre-stated inclusion criteria. RESULTS: A total of 12 studies (n=1167, including 597 patients in the autograft group and 570 patients in the allograft group) were included. The methodological scores for randomized controlled trials ranged from two to four (total score: seven), and for non-randomized prospective studies and cohort studies ranged from four to seven (total score: 12). Except for the Lysholm score (WMD, -1.46; P<0.05) showing a statistically significant difference but a small and clinically irrelevant difference, there was no significant difference between autograft and non-irradiated allograft with respect to the overall IKDC (International Knee Documentation Committee) level, subjective IKDC score, Tegner score, complication, ROM (range of motion), Pivot-shift test, Anterior drawer test, Lachman test, Daniel's one-leg hop test, Harner's vertical jump test, and Instrumented knee laxity test. The results were consistent across a series of sensitivity analyses and subgroup analyses. CONCLUSIONS: Patients with autograft exhibited little clinical advantage over non-irradiated allograft with respect to knee stability, function and side effects. The robustness of the findings might need to be further validated due to the relatively small number of randomized controlled trials. LEVEL OF EVIDENCE: Level II, meta-analysis of prospective studies.

The association between dietary selenium intake and diabetes: a cross-sectional study among middle-aged and older adults.

BACKGROUND: Selenium is an important trace element for human health. Although numerous epidemiological and interventional studies have examined the association between selenium and diabetes, their findings have been inconclusive. Moreover, no research has specifically focused on the association between dietary selenium and diabetes in the Asian population. The objective of this study was to evaluate the relationship between dietary selenium and diabetes in middle-aged and elderly Chinese adults. METHODS: A cross-sectional study including 5,423 subjects was carried out. The basic characteristics, biochemical test results, and dietary intake were collected from each subject for analysis. The adjusted odds ratio (OR) and the corresponding 95% confidence interval (CI) were used to determine the relationship between dietary selenium intake and diabetes through logistic regression. RESULTS: The prevalence of diabetes in the study population was 9.7%, and the average level of dietary selenium intake was 43.51 µg/day. The multivariate adjusted OR was 1.52 (95% CI: 1.01 to 2.28, P = 0.04) for the highest quartile of dietary selenium intake in comparison with the lowest quartile. There was a significant positive association between dietary selenium intake and diabetes (P for trend = 0.03). CONCLUSION: There was a significant positive correlation between dietary selenium intake and the prevalence of diabetes.

[Risk factors for type 2 diabetes complicated with hypertension in adult residents in Liuyang].

OBJECTIVE: To investigate the risk factors for type 2 diabetes complicated with hypertension in adult residents in Liuyang, Hunan Province, P. R. China.
 METHODS: The residents aged at or over 18 were selected through a method of multi-stage cluster random sampling from 10 towns in Liuyang. Questionnaires, physical measurements and laboratory tests were conducted. Type 2 diabetes complicated with hypertension were served as an experimental group, while simple diabetes, non-diabetes and non-hypertension (healthy control), or non-complication and healthy group (simple hypertension, simple diabetes, and healthy group) were served as control group, respectively. Three kinds of logistic regression model were used to analyze the risk factors for type 2 diabetes complicated with hypertension.
 RESULTS: A total of 5 669 residents were included in the analysis, and the response rate was 97.74%. The results showed that the prevalence of type 2 diabetes complicated with hypertension of residents at or over 18 years old in Liuyang was 2.6% (95%CI: 2.2%, 3.1%). Logistic regression analyses demonstrated that for people at or over 60 years old, obesity and abnormal triglyceride were the independent risk factors for type 2 diabetes complicated with hypertension.
 CONCLUSION: Aging, obesity and abnormal triglyceride can increase the risk of type 2 diabetes complicated with hypertension in adult residents in Liuyang.

Single-dose intra-articular bupivacaine after knee arthroscopic surgery: a meta-analysis of randomized placebo-controlled studies.

PURPOSE: The purpose of this meta-analysis was to examine the efficacy and safety of single-dose intra-articular bupivacaine in the management of pain after knee arthroscopic surgery. METHOD: The comprehensive literature search, using MEDLINE, the Cochrane Central Register of Controlled Trials, and Embase databases, was conducted to identify randomized controlled trials that used single-dose intra-articular bupivacaine for postoperative pain. The relative risk (RR), weighted mean difference (WMD), and their corresponding 95 % confidence intervals (CIs) were calculated using RevMan(®) statistical software. RESULT: Twenty-three studies (n = 1287) were included (647 subjects in bupivacaine group and 640 subjects in the control group). Statistically significant differences were observed in the VAS values (WMD -1.1; 95 % CI -1.7 to -0.5), number of patients requiring supplementary analgesia (RR 0.83; 95 % CI 0.74-0.94), and time to first analgesic request (WMD 129.3; 95 % CI 15.4-243.1) among the bupivacaine group when compared to the control group. However, short-term side effects had no significant difference between these two groups (RR 0.73; 95 % CI 0.44-1.24). CONCLUSIONS: On the basis of the currently available literature, single-dose intra-articular bupivacaine was shown to be significantly better than placebo at relieving pain after knee arthroscopic surgery. More high-quality randomized controlled trials with long follow-up are highly required for examining the safety of single-dose intra-articular bupivacaine. Besides, routine use of single-dose intra-articular bupivacaine is still an effective way for pain management after knee arthroscopic surgery.