Higher-order exceptional points in parity-time symmetry and the optical gyroscope.

The practical application of integrated gyroscopes in engineering has not yet been fully realized due to the linear correlation between the Sagnac effect and dimensions. In recent demonstrations, gyroscopes operating near exceptional points (EPs) under parity-time (PT) symmetry have shown significant potential in enhancing their response to rotational rates. However, constructing higher-order EPs with refined physical properties poses a considerable challenge. Additionally, current methods for constructing higher-order EPs with robustness primarily rely on passive cavities, with almost no reports on constructing robust EPs using PT-symmetric systems that encompass both gain and loss. Here, we propose a robust design for a scalable fabrication of higher-order EP gyroscopes with PT-symmetric structure. We investigate the influence of perturbations on the frequency splitting of the higher-order EP gyroscope and demonstrate that it is possible to achieve a resonance splitting eight orders of magnitude higher than that obtained through the classical Sagnac effect. In comparison to the previously proposed PT-symmetric gyroscope, our solution allows a tunable frequency splitting by adjusting the phase shift, making it more measurable at the output power spectrum.

Intense electric field optical sensor based on Fabry-Perot interferometer utilizing LiNbO3 crystal.

A novel intense electric field optical sensor based on Fabry-Perot interferometer utilizing LiNbO3 crystal is proposed and demonstrated. Compared to the traditional bulk-type electric field optical sensors, this sensor unit requires only a LiNbO3 and two collimators, eliminating the need for quarter wave-plate and allowing for measurement of electric field without limitation by half wave voltage. The Vernier effect, generated by birefringence of LiNbO3, is utilized to enhance the sensitivity of electric field measurement, which does not require additional reference cavity. Both theoretical and experimental results illustrate that the wavelength shift of the sensor is linear function of the measured electric field. In the range of 0∼1010 kV/m, the sensor's measurement sensitivity is 2.22 nm/E (V/µm) with detection limit of 1.27 × 10-2 E. Additionally, an MZI is proposed for temperature compensation, resulting in a standard deviation of spectrum variation after compensation of only 5.01 × 10-3. Applications using this sensor confirmed that it is expected to find widespread use in measurements of intense transient electric fields.

Mueller transform matrix neural network for underwater polarimetric dehazing imaging.

Polarization dehazing imaging has been used to restore images degraded by scattering media, particularly in turbid water environments. While learning-based approaches have shown promise in improving the performance of underwater polarimetric dehazing, most current networks rely heavily on data-driven techniques without consideration of physics principles or real physical processes. This work proposes, what we believe to be, a novel Mueller transform matrix network (MTM-Net) for underwater polarimetric image recovery that considers the physical dehazing model adopting the Mueller matrix method, significantly improving the recovery performance. The network is trained with a loss function that combines content and pixel losses to facilitate detail recovery, and is sped up with the inverse residuals and channel attention structure without decreasing image recovery quality. A series of ablation experiment results and comparative tests confirm the performance of this method with a better recovery effect than other methods. These results provide deeper understanding of underwater polarimetric dehazing imaging and further expand the functionality of polarimetric dehazing method.

miR-31-5p modulates cell progression in lung adenocarcinoma through TNS1/p53 axis.

OBJECTIVE: To clarify the modulatory mechanism of miR-31-5p in lung adenocarcinoma (LUAD) progression in vivo and in vitro. METHODS: The Cancer Genome Atlas (TCGA) database was employed to access LUAD-related miRNA and mRNA expression data. Downstream targets of miR-31-5p were predicted by public databases. The interaction between miR-31-5p and TNS1 was determined by dual-luciferase reporter assay. Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to measure miR-31-5p and TNS1 expression levels in LUAD cells. Western blot was introduced to test protein expression levels of TNS1, p53, and apoptosis-related proteins. In-vitro functional assays were conducted to evaluate the biological effects of miR-31-5p on cell proliferation, colony formation, migration, and apoptosis. In-vivo tumor xenograft experiment was applied to examine the effects of miR-31-5p on LUAD tumor growth, followed by immunochemistry assays for assessing TNS1 and p53 expression levels in the tumor tissue. RESULTS: miR-31-5p was prominently upregulated in LUAD tissue and was identified to present a similar trend in LUAD cell lines H1299, H23, and A549. miR-31-5p overexpression exerted an active role in cell proliferation and migration, but it suppressed cell apoptosis. Additionally, a reverse correlation between miR-31-5p and TNS1 regarding the expression level was identified, and TNS1 was verified to be a direct target of miR-31-5p. Besides, it was further validated by the rescue experiments that the tumor-promoting effects of miR-31-5p on LUAD cell functions were attenuated by TNS1 overexpression to some extent. The results based on the tumor xenograft experiment revealed that LUAD cell growth could be facilitated by miR-31-5p via the TNS1/p53 axis. CONCLUSION: miR-31-5p facilitates LUAD cell progression mediated by the TNS1/p53 axis.

Response of PM2.5-bound elemental species to emission variations and associated health risk assessment during the COVID-19 pandemic in a coastal megacity.

The coronavirus (COVID-19) pandemic is disrupting the world from many aspects. In this study, the impact of emission variations on PM2.5-bound elemental species and health risks associated to inhalation exposure has been analyzed based on real-time measurements at a remote coastal site in Shanghai during the pandemic. Most trace elemental species decreased significantly and displayed almost no diel peaks during the lockdown. After the lockdown, they rebounded rapidly, of which V and Ni even exceeded the levels before the lockdown, suggesting the recovery of both inland and shipping activities. Five sources were identified based on receptor modeling. Coal combustion accounted for more than 70% of the measured elemental concentrations before and during the lockdown. Shipping emissions, fugitive/mineral dust, and waste incineration all showed elevated contributions after the lockdown. The total non-carcinogenic risk (HQ) for the target elements exceeded the risk threshold for both children and adults with chloride as the predominant species contributing to HQ. Whereas, the total carcinogenic risk (TR) for adults was above the acceptable level and much higher than that for children. Waste incineration was the largest contributor to HQ, while manufacture processing and coal combustion were the main sources of TR. Lockdown control measures were beneficial for lowering the carcinogenic risk while unexpectedly increased the non-carcinogenic risk. From the perspective of health effects, priorities of control measures should be given to waste incineration, manufacture processing, and coal combustion. A balanced way should be reached between both lowering the levels of air pollutants and their health risks.

[Reflections on supervision strategies of new Tibetan drug registration].

Tibetan medicine is an essential part of Chinese medicine and has unique theoretical experience and therapeutic advantages. According to the development principle of inheriting the essence, sticking to the truth, and keeping innovative, the supervision department should give clear and reasonable guidance considering the characteristics of Tibetan medicine, establish a standard system for quality control, clinical verification and evaluation, and accelerate the research and commercialization of new drugs. In view of the needs of drug supply-side reform and the current situation of Tibetan medicine and new pharmaceutical research, we ponder and provide suggestions on the confusion faced by the current supervision of Tibetan drug registration, hoping to contribute to the supervision strategy of Tibetan drug registration and the high-quality development of Tibetan medicine industry.

Suppression of Kerr-effect induced error in resonant fiber optic gyro by a resonator with spun fiber.

In order to suppress Kerr-effect induced error in resonant fiber optic gyro (RFOG), a resonator based on spun fiber (SF) is proposed for the first time. The theory of the Kerr-effect induced error in gyro is analyzed first and the suppression method for this issue is explained, highlighting the advantages of circular state of polarization (CSOP) light and SF. Then the structure design and optimization of the resonator are completed to guide resonator fabrication and meet the better noise suppression requirement. Finally, the gyro experiment indicates that the resonator based on SF can suppress the Kerr-effect induced error by at least 96.6 % without a power compensation structure, which is of great significance for simplifying the system. In addition, the method proposed in this article first confirms the potential of CSOP light in optical noise and error suppression of RFOG.

Incoherence suppression method of optical noises in a resonant fiber optic gyro based on the circularly polarized light propagation mechanism in a resonator.

Resonant fiber optic gyros (RFOGs) generally use fiber ring resonator propagating linearly polarized light, so it is inevitably affected by coherent optical noises between two counterpropagation beams such as nonlinear effect and backscattering noise. So, we propose the incoherent suppression method of optical noises in a RFOG based on the circularly state of polarization (CSOP) light. The spun-fiber is used to fabricate a resonator that can realize the reciprocal transmission of CSOP light for the first time, and the highly reciprocal signal processing scheme is applied in RFOG based on the Faraday effect. We demonstrate that the designed resonator realizes orthogonal separation of backscattered light thereby suppressing the backscattering noise, and we confirm that the reciprocal CSOP light can greatly reduce the nonlinear effect due to incoherence. With the closed-loop method based on the Faraday effect and spun-fiber resonator, whose finesse is 6.6 with a length of 11-meter spun-fiber and 6-meter single-polarization fiber, the long-term stability and short-term stability of a RFOG have been greatly improved. The incoherence method based on a reciprocal CSOP light propagation mechanism has great potential in the suppression of coherence optical noises in a RFOG, which provides a new, to the best of our knowledge, idea to solve the problem.

A Spatial-Temporal Approach Based on Antenna Array for GNSS Anti-Spoofing.

The presence of spoofing signals poses a significant threat to global navigation satellite system (GNSS)-based positioning applications, as it could cause a malfunction of the positioning service. Therefore, the main objective of this paper is to present a spatial-temporal technique that enables GNSS receivers to reliably detect and suppress spoofing. The technique, which is based on antenna array, can be divided into two consecutive stages. In the first stage, an improved eigen space spectrum is constructed for direction of arrival (DOA) estimation. To this end, a signal preprocessing scheme is provided to solve the signal model mismatch in the DOA estimation for navigation signals. In the second stage, we design an optimization problem for power estimation with the estimated DOA as support information. After that, the spoofing detection is achieved by combining power comparison and cross-correlation monitoring. Finally, we enhance the genuine signals by beamforming while the subspace oblique projection is used to suppress spoofing. The proposed technique does not depend on external hardware and can be readily implemented on raw digital baseband signal before the despreading of GNSS receivers. Crucially, the low-power spoofing attack and multipath can be distinguished and mitigated by this technique. The estimated DOA and power are both beneficial for subsequent spoofing localization. The simulation results demonstrate the effectiveness of our method.

Compensation method for temperature error of fiber optical gyroscope based on relevance vector machine.

Aiming to improve the bias stability of the fiber optical gyroscope (FOG) in an ambient temperature-change environment, a temperature-compensation method based on the relevance vector machine (RVM) under Bayesian framework is proposed and applied. Compared with other temperature models such as quadratic polynomial regression, neural network, and the support vector machine, the proposed RVM method possesses higher accuracy to explain the temperature dependence of the FOG gyro bias. Experimental results indicate that, with the proposed RVM method, the bias stability of an FOG can be apparently reduced in the whole temperature ranging from -40°C to 60°C. Therefore, the proposed method can effectively improve the adaptability of the FOG in a changing temperature environment.

Clinical evaluation of platelet-rich plasma therapy for osteonecrosis of the femoral head: A systematic review and meta-analysis.

OBJECTIVE: This meta-analysis aims to assess the efficacy and safety of platelet-rich plasma (PRP) for osteonecrosis of the femoral head (ONFH). METHODS: We comprehensively searched randomized controlled trials in PubMed, Web of Science, EMBASE, the Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure, China Science and Technology Journal Database, WanFang, and Chinese BioMedical Literature Database from inception until October 25, 2024. The literature on the clinical efficacy of autologous PRP for ONFH was collated. According to the inclusion and exclusion criteria, the literature was screened, quality evaluated and the data was extracted. Meta-analysis was carried out with the software Review Manager 5.4.1 software and Stata 17.0 software. In addition, potential publication bias was detected by the funnel plot test and Egger's test. The GRADE system was used to evaluate the quality of evidence for outcome indicators. RESULTS: Fourteen studies involving 909 patients were included in this study. Compared with non-PRP, PRP exhibited significant improvements in the Harris hip score (HHS) at 3 months (MD = 3.58, 95% Cl: 1.59 to 5.58, P = 0.0004), 6 months (MD = 6.19, 95% Cl: 3.96 to 8.41, P < 0.00001), 12 months (MD = 4.73, 95% Cl: 3.24 to 6.22, P < 0.00001), ≥ 24 months (MD = 6.83, 95% Cl: 2.09 to 11.59, P = 0.0003), and the last follow-up (MD = 6.57, 95% Cl: 4.81 to 8.33, P < 0.00001). The PRP also showed improvement in HHS compared to baseline than the non-PRP at 3 months (MD = 3.60, 95% Cl: 1.26 to 5.94, P = 0.003), 6 months (MD = 6.17, 95% Cl: 3.74 to 8.61, P < 0.00001), 12 months (MD = 5.35, 95% Cl: 3.44 to 7.25, P < 0.00001), ≥ 24 months (MD = 8.19, 95% Cl: 3.76 to 12.62, P = 0.0003), and the last follow-up (MD = 6.94, 95% Cl: 5.09 to 8.78, P < 0.00001). The change in visual analog scale (VAS) score 3 months post intervention (MD = -0.33, 95% Cl: -0.52 to -0.13, P = 0.001), 6 months (MD = -0.69, 95% Cl: -0.90 to -0.48, P < 0.00001), 12 months (MD = -0.75, 95% Cl: -1.05 to -0.46, P < 0.00001), ≥ 24 months (MD = -1.05, 95% Cl: -1.20 to -0.89, P < 0.00001), and the last follow-up (MD = -0.75, 95% Cl: -0.97 to -0.54, P < 0.00001). The PRP also showed a decrease in VAS score compared to baseline than the non-PRP at 3 months (MD = -0.29, 95% Cl: -0.41 to -0.17, P = 0.003), 6 months (MD = -0.63, 95% Cl: -0.96 to -0.30, P = 0.0002), 12 months (MD = -0.78, 95% Cl: -1.22 to -0.33, P = 0.0006), ≥ 24 months (MD = -1.11, 95% Cl: -1.27 to -0.96, P < 0.00001), and the last follow-up (MD = -0.74, 95% Cl: -1.05 to -0.43, P < 0.00001). Additionally, it was found that the PRP group had the advantages in the following aspects: collapse rate of the femoral head (RR = 0.33, 95% Cl: 0.17 to 0.62, P = 0.0006), rate of conversion to total hip arthroplasty (RR = 0.37, 95% Cl: 0.18 to 0.74, P = 0.005), and overall complications (RR = 0.33, 95% Cl: 0.13 to 0.83, P = 0.02). The GRADE evidence evaluation showed overall complication as very low quality and other indicators as low quality. CONCLUSION: There is limited evidence showing benefit of PRP therapy for treatment of ONFH patients, and most of this evidence is of low quality. Caution should therefore be exercised in interpreting these results. It is recommended that future research involve a greater number of high-quality studies to validate the aforementioned conclusions. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero/ #recordDetails, CRD42023463031.

Research on the thermal relaxation effect of nonplanar four-frequency differential laser gyro.

The nonplanar four-frequency differential laser gyro (NFFDLG, also called ZLG in the United States) has many advantages, such as the absence of mechanical noise, a whole solid state, high stability of scale factor, and no time delay. Because of its excellent performance, NFFDLG is currently the subject of research. In this paper, the error induced by the thermal relaxation effect is investigated both theoretically and experimentally, and some methods and conclusions that could restrain this error effectively are proposed. The experiment data confirm reliably that NFFDLG has a thermal relaxation effect error during overturning. At the same time, it is pointed out that the error can be minimized by reducing the stop interval. Furthermore, since the sum frequency could be affected more seriously by the overturning thermal relaxation effect than the difference frequency could, the former one can be used as one more sensitive condition in actual applications. As far as we know, the overturning thermal relaxation effect was first investigated in China, which is even not mentioned publicly.

Effect of pilose antler polypeptide on the mechanism of bone homeostasis in osteoporosis.

Osteoporosis stands out as a prevalent metabolic disorder, bearing significant repercussions on human well-being and overall quality of life. It remains an urgent concern within the global public health framework due to its widespread occurrence. Osteoporosis arises from an abnormal metabolism in osteoblasts and osteoclasts, resulting in a disruption of the delicate equilibrium between bone formation and bone resorption. Within this context, deer antler peptides emerge as natural active compounds, wielding a pivotal role in governing the differentiation, proliferation, and mineralization of osteoblasts, as well as influencing the activity of osteoclasts. This article aims to consolidate our comprehension of the mechanisms underpinning the dynamic balance between bone formation and resorption, meticulously orchestrated by osteoblasts and osteoclasts in osteoporosis. Furthermore, it offers a comprehensive overview of how deer antler peptides, through their modulation of relevant signaling pathways, contribute to the enhancement of bone homeostasis. These insights deepen our understanding of the pathological processes through which deer antler peptides ameliorate bone homeostasis, while also presenting novel strategies for osteoporosis management.

Atmospheric saccharides over the East China Sea: Assessment of the contribution of sea-land emission and the aging of levoglucosan.

A one-year observation of aerosols on a remote island was conducted and saccharides were applied to reveal the behaviors of organic aerosol in the East China Sea (ECS). The seasonal fluctuations of total saccharides were relatively small, with annual mean concentration of 64.82 ± 26.88 ng/m3, contributing 10.20 % and 4.90 % to WSOC and OC, respectively. However, the individual species showed significant seasonal variations due to the differences in both the emission sources and the influencing factors between marine and terrestrial areas. Anhydrosugars was the highest species and showed little diurnal variation in air mass from land areas. Primary sugars and primary sugar alcohols showed higher concentrations in blooming spring and summer and were higher in daytime than nighttime due to intense biogenic emissions both in marine and mainland areas. Accordingly, secondary sugar alcohols showed obvious different diurnal variation with ratios of day/night reducing to 0.86 in summer but even increasing to 1.53 in winter, attributing to the additional impact of secondary transmission process. Source appointment suggested that biomass burning emission (36.41 %) and biogenic emission (43.17 %) were the main causes of organic aerosol, while anthropogenic related secondary process and sea salt injection accounted for 13.57 % and 6.85 %, respectively. We further elucidate that the biomass burning emission might be underestimated, as levoglucosan undergoes degradation processes in the atmosphere, which are affected by various atmospheric physicochemical factors, and the degradation degree is particularly severe in remote areas like the oceans. In addition, significantly low ratio of levoglucosan to mannosan (L/M) occurred in air mass from marine area, indicating that levoglucosan was likely be more fully aged after hovering over a large-scale of oceanic area.

PM2.5-bound polycyclic aromatic hydrocarbons of a megacity in eastern China: Source apportionment and cancer risk assessment.

Ninety-six fine particulate matter (PM2.5) samples covering four seasons from October 2020 to August 2021 were collected at a 'super' site in Hangzhou, a megacity in eastern China. These samples were analyzed to determine the sources and potential cancer risks to humans of 16 United States Environmental Protection Agency priority polycyclic aromatic hydrocarbons (PAHs). The average concentrations of the PAHs in PM2.5 in autumn, winter, spring, and summer were 8.35 ± 4.90, 27.9 ± 13.6, 8.3 ± 5.97, and 1.05 ± 0.50 ng/m3, respectively, and with an annual average of 11.9 ± 13.2 ng/m3. The source apportionment by positive matrix factorization analysis indicated that, based on the yearly average, the major sources of PAHs were traffic emissions (38.2 %), coal combustion (28.9 %), coke (21.7 %), and volatilization (11.1 %). Strong correlations between high concentrations of carbonaceous aerosols and high-molecular-weight PAHs in winter could be attributed to incomplete combustion. Long-range transport of air from the sea to the southeast resulted in low concentrations of carbonaceous aerosols and low-molecular-weight PAHs in summer. Trajectory clustering and the potential source contribution function both indicated that the Yangtze River Delta was the main source region of PAHs for PM2.5 in Hangzhou in spring and summer. In autumn and winter, it was dominated by long-range transport from northern China. Lifetime lung cancer risk assessment revealed that the PAHs in PM2.5 impose moderate human health risks in Hangzhou due to traffic emissions. The results of this study provide important information for policymakers to establish abatement strategies to reduce PAH emissions in Hangzhou, and perhaps other urban centers across China.

Relationship between light absorption properties of black carbon and aerosol origin at a background coastal site.

As a potent climate forcer, black carbon (BC) optical properties can have significant impacts on the regional meteorology and climate. To unveil the seasonal differences of BC and its contribution by various emission sources, a one-year continuous monitoring of atmospheric aerosols was conducted at a background coastal site in Eastern China. By comparing the seasonal and diurnal patterns between BC and elemental carbon, we observed that BC were evidently aged with varying extents among all four seasons. The light absorption enhancement of BC (Eabs) was calculated as 1.89 ± 0.46, 2.40 ± 0.69, 1.91 ± 0.60, and 1.34 ± 0.28, from spring to winter, respectively, indicating that BC was more aged in summer. Contrary to the negligible impact of pollution levels on Eabs, the patterns of air masses arriving to the sampling site had a significant impact on the seasonal optical characteristics of BC. Sea breezes evidently exhibited higher Eabs than land-sourced breezes, and BC was more aged and light-absorbing with an increased contribution of marine airflows. By applying a receptor model, we resolved six emission sources as ship emission, traffic emission, secondary pollution, coal combustion, sea salt, and mineral dust. The mass absorption efficiency of BC for each source was estimated, showing the highest from the ship emission sector. This explained the highest Eabs observed in summer and sea breezes. Our study highlights that curbing emission from shipping activities is beneficial for reducing the warming effect of BC in coastal areas, particularly in the context of future rapid development of international shipping.

Seasonal source identification and formation processes of marine particulate water soluble organic nitrogen over an offshore island in the East China Sea.

Water soluble organic nitrogen (WSON) had great influences on the aerosol chemistry, hygroscopicity, marine primary productivity, as well as nitrogen biogeochemical cycles. Aerosol sampling was conducted over an offshore island in the East China Sea in four seasons of 2019, aiming to reveal the seasonal sources and secondary formation processes of marine WSON. The annual mean WSON concentration reached 1.05 ± 1.72 µg/m3 with a mean WSON/WSTN fraction of 27 %. In spring, WSON was associated with combustion emissions. The liquid-phase reaction of NH3/NH4+ with VOCs was a potential secondary formation process of WSON. In summer, WSON was mainly formed through the gaseous phase oxidation of marine biogenic precursors. In autumn, WSON showed miscellaneous sources from agricultural activities, biomass burning, and fossil fuel combustion. In addition to the contribution from primary urea, WSON could be also affected by the oxidation of biological proteinaceous matters. This explained the highest WSON concentrations and WSON/WSOC ratios in autumn. In winter, WSON was probably emitted from sea spray aerosols via the bubble-bursting processes. This study indicated that the sources of WSON over the coastal waters in the East China Sea were quite diverse, highlighting the need of more detailed characterization of marine WSON at the molecular level.

Polishing micropollutants in municipal wastewater, using biogenic manganese oxides in a moving bed biofilm reactor (BioMn-MBBR).

Conventional wastewater treatment plants (WWTPs) cannot remove organic micropollutants efficiently, and thus various polishing processes are increasingly being studied. One such potential process is utilising biogenic manganese oxides (BioMnOx). The present study operated two moving bed biofilm reactors (MBBRs) with synthetic sewage as feed, one reactor feed was spiked with Mn(II) which allowed the continuous formation of BioMnOx by Mn-oxidising bacteria in the suspended biofilms (i.e. BioMn-MBBR). Spiking experiments with 14 micropollutants were conducted to investigate if BioMnOx combined with MBBR could be utilised to polish micropollutants in wastewater treatment. Results show enhanced removal by BioMn-MBBR over control MBBR (without BioMnOx) for specific micropollutants, such as diclofenac (36% vs. 5%) and sulfamethoxazole (80% vs. 24%). However, diclofenac removal was significantly inhibited when municipal wastewater was fed, and a further batch experiment demonstrates the reduced removal of diclofenac could be due to (unusual) higher pH in municipal wastewater compared to synthetic sewage. A shift in bacterial community was also observe in BioMn-MBBR over long-term operation. Overall, BioMn-MBBR in this study shows great potential for practical application in removing a larger range of micropollutants, which could be applied as an efficient polishing step for typical municipal wastewater.

Prevalence and Distribution of Osteopenia in Chinese Population: A System Review and Meta-Analysis.

Background: The number of patients with osteoporosis ranks first in the world in China and as a precursor state of osteoporosis, the number and incidence of osteopenia are much higher than that of osteoporosis. This meta-analysis was conducted to evaluate the incidence and distribution of osteopenia in adults in mainland of China over 10 years to provides reference for the early prevention of osteoporosis and policymaking. Methods: Relevant data were extracted from the databases including CNKI, Wanfang, VIP, Web of Science, PubMed, EMBASE, and Medline about the surveys on osteoporosis and bone loss from 2010 to 2021 by searching. The random effects model was adopted for Meta-analysis, and the funnel plot was used to test publication bias. Results: Forty-seven literatures were included in this study, covering 27 provinces and 38 regions in the mainland of China, with the study of 135,688 cases, showing that the prevalence of osteopenia in adults in the past decade was 28.3%(95% CI 24-33%), aged 40∼60 yr old, reaching the highest level. The incidence of osteopenia in males was higher than that in females (P<0.05), without significant difference in south and north China. Conclusion: There is a large population with osteopenia in China, especially middle-aged population, both men and women should pay attention to osteopenia to delay its further progression.

Cost-efficient microbial electrosynthesis of hydrogen peroxide on a facile-prepared floating electrode by entrapping oxygen.

Microbial electrosynthesis of hydrogen peroxide is receiving growing interest for a green substitute for anthraquinone process.However, poor oxygen transmission of electrode remains an obstacle to enhance H2O2 production rate without aeration. Here, a superhydrophobic natural air diffusion floating electrode (NADFE), which naturally and efficiently entraps O2 in the air, was proposed for the first time to improve microbial electrosynthesis of H2O2. Furthermore, a one-step calcined electrode preparation method was developed to reduce energy consumption further. In the microbial electrolysis cell with the NADFE, a high H2O2 production rate of 39 mg/L/h and current efficiency of 86% were achieved without aeration. The production rate of H2O2 was 2.2 times that of a gas diffusion electrode. Importantly, the energy consumption was 34.3 times lower than an electrochemical system. Therefore, the high H2O2 production rate and current efficiency, and low energy consumption of the process provide a superior alternative for environmental remediation.