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Enhancements of stationary planetary waves (SPWs) and traveling planetary waves (TPWs) are commonly observed in the middle atmosphere during sudden stratospheric warming (SSW) events. Based on the least square fitting method (Wu et al., 1995), numerous studies have used satellite measurements to investigate the characteristics of TPWs during SSWs but ignored the effect of the SPWs. However, a rapid and large change in the SPWs during SSWs may lead to significant disturbances in the amplitude of derived TPWs. In this study, we present a new methodology for obtaining the amplitudes and wavenumbers of traveling quasi-5-day oscillations (Q5DOs) in the middle atmosphere during major SSWs. Our new fitting method is developed by inhibiting the effect of a rapid and large change in SPWs during SSWs. We demonstrate the effectiveness of the new method using both synthetic data and satellite observations. The results of the simulations indicate that the new method can suppress the aliasing from SPWs and capture the real variations of TPWs during SSWs. Based on the geopotential height data measured by the Aura satellite from 2004 to 2021, the variations of traveling Q5DOs during eight mid-winter major SSWs are reevaluated using the new method. The differences in the fitted amplitudes between the least square fitting method and the new method are usually over 100 m during the SSW onsets. Our analysis indicates that previously-reported Q5DOs during SSWs might be contaminated by SPWs, which leads to both overestimation and underestimation in the amplitudes of the traveling Q5DOs.

Combining two meteor radar observations at mid-latitudes and MERRA2 reanalysis data, we report an extraordinary quasi-16-day wave (Q16DW) activity in the mesosphere and lower thermosphere (MLT) from about October 2013 to January 2014. The Q16DW is not only active for a long period, but also unrelated to stratospheric sudden warming (SSW), while 7-year radar observations indicate that strong waves and oscillations in the MLT at mid-latitudes occur generally in winter, and are almost always associated with SSW and stratospheric final warming (SFW), except the extraordinary Q16DW. Meanwhile, during the SSW and SFW in February and March 2014, the observation and reanalysis data show that an intense Q16DW arises in the stratosphere but is not present in the MLT. The two Q16DWs are obviously distinguished from each other. The exceptional Q16DW shows a slowly downward phase progression from the MLT to the troposphere with predominant wavenumber 1, while the second Q16DW has a steeper vertical phase in the stratosphere with predominant wavenumber 2. Although the eastward winds prevail, these Q16DWs are weakened and evanescent in the region with the westward wind and negative refractive index. EP flux vector indicates that these waves originate mainly from the lower atmosphere at mid- and high-latitudes, and are intensified in the middle stratosphere. The first Q16DW may make a little contribution to polar vortex intensification due to small EP flux divergence. However, the Q16DW in the SSW has a strong negative divergence almost in the whole polar stratosphere, implying an important role in the stratospheric zonal wind reduction in the SSW. Graphical Abstract

Ischemic cerebrovascular disease is one of the main diseases threatening human health and survival and is a commonly occurring disease in neurology. Due to its high disability rate, ischemic cerebrovascular disease is one of the most important diseases to be prevented and treated at present. The risk factors of cerebral ischemia include atherosclerosis, hypertension, hyperlipidemia, and blood viscosity caused by thrombocytosis. After cerebral ischemia, cerebral ischemia-reperfusion injury may be induced by oxidative stress (OS), inflammatory reaction, nitric oxide damage, apoptosis, excitatory amino acid toxicity, calcium (CaWe conducted a literature search for published manuscripts hesperidin in ischemia/reperfusion up to December 2021 in common English databases (i.e., PubMed, EMBASE, Web of Science, SpringerLink, Wiley, Cochrane Library) and Chinese databases [Chinese BioMedical Literature Service System (CBM), WANFANG database, China Knowledge Resource Integrated Database (CNKI)].In this article, we reviewed the mechanisms of action of hesperidin in the treatment of cerebral ischemia, including antioxidant stress, anti-inflammatory reaction, anti-atherosclerosis, anti-thrombosis, anti-apoptosis, and nitric oxide regulation.In this narrative review, Hesperidin exhibits antioxidant stress, anti-platelet aggregation, vasodilation, anti-atherosclerotic, anti-inflammatory, anti-apoptotic, hypolipidemic, anti-tumor, cardiovascular protection, and nitric oxide-release regulatory properties Such a comprehension of the recent progress of hesperidin will help identify biomarkers for diagnosis and therapeutic targets to cerebral ischemia.

Anomalous changes of zonal wind quasi-biennial oscillation (QBO) in winter 2015−2016 have received close attention. Combining radiosonde and satellite observations and reanalysis data, we investigate anomalous changes in temperature and ozone QBOs from the lower to middle stratosphere. As wind shear direction is reversed due to unexpected changes of zonal wind QBO at about 24−30 km, the shortest cold phase at 21−27 km appears in temperature QBO. This is different from the completely interrupted westward phase in zonal wind QBO, while the longest cold phase above almost 27 km lasts for 2−3 years from 2015 to 2017, owing to the absence of corresponding warm phase. Meridional scale reduction of temperature QBO causes a small temperature anomaly, thus the thermal wind relationship looks seemingly different from that in the other regular QBO cycles. QBO in the ozone mixing ratio anomaly shows a double-peak with inverse phase, and its phase below (above) 30 km is in agreement with (opposite to) the phase of temperature QBO because of different control mechanisms of ozone. Following temperature QBO variation, QBO in the ozone mixing ratio anomaly exhibits a less positive phase at 20−30 km in 2016−2017, and a very long positive phase above 30 km from 2015 to 2017. QBO in total column ozone shows a small peak in winter 2016−2017 since ozone is mainly concentrated at 20 to 30 km. Anomalous changes of temperature and ozone QBOs due to unexpected QBO zonal wind variation can be well-explained according to thermal wind balance and thermodynamic balance.

Oral squamous cell carcinoma (OSCC) is the most predominant type of oral cancer, featured with poor prognosis and high mortality. Circular RNA (circRNA) exerts its function in a variety of human cancers, including OSCC. Circ_0005050, as a novel circRNA, has not been well explored in OSCC so far. This study centered on investigating the impact of circ_0005050 on OSCC cell growth and its molecular mechanism. RNA or protein expression was detected by RT-qPCR or western blot analysis. Functional assays were employed to uncover the changes of OSCC cell biological behaviors. Mechanistic assays were done to verify the underlying mechanism of circ_0005050 in OSCC cells. According to the collected data, circ_0005050 was significantly up-regulated in OSCC cells compared to normal cells. Circ_0005050 depletion hampered proliferative ability of OSCC cells while promoting cell apoptotic ability. As for mechanism analyses, circ_0005050 knockdown led to the reduction of STAT3 expression and JAK/STAT3 signaling pathway activity. Moreover, circ_0005050 competitively bound to miR-23a-3p and miR-625-5p to up-regulate STAT3, thus prompting malignant behaviors of OSCC cells. In conclusion, circ_0005050 regulates miR-23a-3p/miR-625-5p/STAT3 axis to activate JAK/STAT3 signaling pathway, consequently facilitating OSCC cell proliferation and inhibiting cell apoptosis.

Although the characteristics of the traveling 10-day waves (10DWs) above the middle stratosphere have been well explored, little research has been performed on the counterpart in the troposphere and lower stratosphere (TLS). In the present study, we use radiosonde observations and MERRA-2 data in 2020 to characterize traveling 10DWs in mid-latitudes in the TLS. Single-site observations in both hemispheres show that strong 10DW activities are always accompanied by strong eastward jets (10-13 km). MERRA-2 data indicates that in the troposphere the eastward-propagating modes with larger wavenumbers, i.e., E3, E4, E5 and E6 are dominant. While in the lower stratosphere the eastward- and westward-propagating modes with small zonal wavenumbers e.g., 1 and 2, are dominant. Further research on E3, E4, E5 and E6 modes in the troposphere of both hemispheres shows that all the wave activities are positively correlated to the background zonal wind. The refractive index squared reveal that a strong eastward jet is suitable for these four modes to propagate. However, just above the jet, the eastward wind decreases with altitude, and a thick evanescence region emerges above 15 km. E3, E4, E5 and E6 10DWs cannot propagate upward across the tropopause; as such this can explain why these four modes are weak or even indiscernible in the stratosphere and above. In the troposphere, E5 10DW at 32°S is the most dominant mode in 2020. A case study of the anomalously strong E5 10DW activity on May 12, 2020 indicates that the wave amplification resulted from the upward and equatorward transmission of wave energy flows. Moreover, the tropopause and equatorial region can prevent the propagations of wave energy flows of E5 10DW.

Using Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) data in the northern hemisphere at the 10 hPa level, we compared the stratospheric evolution of temperature and geopotential height during two major sudden stratosphere warming events (SSWs) that occurred in the Arctic winter of 2018 and 2019. In the prewarming period, poleward temperature-enhanced regions were mainly located around 120°E with a displaced vortex and around 120°E and 60°W with splitting vortices. The evolution of geopotential height indicated that these temperature-enhanced regions were both on the western side of high-latitude anticyclones. In the postwarming period, the polar vortex turned from splitting to displacement in the 2018 SSW but from displacement to splitting in the 2019 SSW. Both transitions were observed over the Atlantic region, which may have been caused by anticyclones moving through the polar region. Our findings revealed that the evolution of the anticyclone is important during SSWs and is closely related to temperature-enhanced regions in the prewarming periods and to transitions of the polar vortices in postwarming periods.

This study presents an analysis of the quasi-16-day wave (Q16DW) at three stations in the middle latitudes by using a meteor radar chain in conjunction with Aura Microwave Limb Sounder temperature data and MERRA2 (Modern-Era Retrospective Analysis for Research and Applications, Version 2) reanalysis data from 2008 to 2017. The radar chain consists of three meteor radar stations located at Mohe (MH, 53.5°N, 122.3°E), Beijing (BJ, 40.3°N, 116.2°E), and Wuhan (WH, 30.5°N, 114.6°E). The Q16DW wave exhibits similar seasonal variation in the neutral wind and temperature, and the Q16DW amplitude is generally strong during winter and weak around summer. The Q16DW at BJ was found to have secondary enhancement around September in the zonal wind, which is rarely reported at similar latitudes. The latitudinal variations of the Q16DW in the neutral wind and temperature are quite different. The Q16DW at BJ is the most prominent in both neutral wind components among the three stations and the Q16DW amplitudes at MH and WH are comparable, whereas the wave amplitude in temperature decreases with decreasing latitude. The quasi-geostrophic refractive index squared at the three stations in the period from 2008 to 2017 was revealed. The results indicate that the Q16DW in the mesosphere and lower thermosphere (MLT) at MH has a limited contribution from the lower atmosphere. Around March and October, the Q16DW in the troposphere at BJ can propagate upward into the MLT region, whereas at WH, the contribution to the Q16DW in the MLT region is largely from the mesosphere.

Glioma is a common primary craniocerebral malignant tumor, due to the lack of specificity of imaging examination and clinical manifestations, its diagnostic accuracy is relatively low, which may result in misdiagnosis and missed diagnosis. The apparent diffusion coefficient (ADC) in magnetic resonance diffusion weighted imaging (DWI) can reflect the histological characteristics of gliomas, which can be widely applied to classify gliomas and evaluate the extent of metastasis of glioma. The present study aimed to assess the clinical value of magnetic resonance DWI in the pathological grading of glioma and its therapeutic application in clinical surgery.This article retrospectively analyzed the clinical data of 41 patients with glioma confirmed by surgical pathology results from January 1, 2019 to March 31, 2020 in the People's Hospital of Gaozhou. Among them, 16 patients had low-grade gliomas [World Health Organization (WHO) grade I-II] and 25 patients had high-grade gliomas (WHO grade III-IV). They were subjected to conventional T1WI and T2WI plain scans, along with DWI and enhanced scans before surgery. The ADC values of the glioma parenchyma, the peritumoral edema area, the surrounding white matter, and the contralateral normal white matter were measured. We selected some tumor tissues for pathological analysis as well, and conducted pathological grading according to WHO grading standards.We compared and evaluated the ADC values of the observed areas for low-grade gliomas and high-grade gliomas. The ADC values of low-grade gliomas in the tumor parenchyma, peritumoral edema, and white matter around the edema area were significantly lower than those of high-grade gliomas, and the differences were statistically significant (P0.05). The difference in ADC values of normal white matter between the two groups of patients was not statistically significant (P=0.125).DWI has prognostic predictive value in the preoperative differential diagnosis and pathological classification of gliomas. This advanced technology can verify the extent of glioma infiltration in the surrounding brain tissue. It can help clinicians formulate a safer and more effective therapeutic strategy by providing accurate information on prognostic evaluation before the successful surgical intervention of gliomas.

Intracranial hemorrhage following spinal surgery is an infrequent but severe complication. Due to its rarity, the etiology, clinical characteristics, and treatment have not yet been fully elucidated. This literature review analyzed the incidence, clinical manifestations, hemorrhage location, current therapeutic strategies, location of operation, and interval time between surgery and bleeding. The objectives of the article were to provide insights for clinicians to promptly identify and prevent potential cases of intracranial hemorrhage.The authors queried PubMed and Web of Science databases using predefined keywords and included published literature reporting on intracranial hemorrhage after spinal surgery. Relevant case reports, case series, and reviews describing the mechanism of intracranial hemorrhage after spinal surgery and meeting diagnostic criteria for intracranial hemorrhage related to spinal surgery were included. Clinico-demographc data, presentations symptoms, location, index surgery type, and neurological outcomes after brain hemorrhage. Oxford Centre Level of Evidence guidelines was used to evaluate the quality of included studies. Descriptive statistics were used to synthesize the results.A total of 80 publications of level of evidence IV involving 108 patients with median age at diagnosis was 58.5 years (inter-quartile range: 6-85) were analyzed. The incidence of intracranial hemorrhage was 0.08-0.37% among patients who underwent spinal surgery, and this complication occurred predominantly within 48 hours postoperatively. The initial presentation included headache, reduced level of consciousness, dysarthria, nausea, vomiting, hearing loss, blurred vision, neck rigidity, and delayed recovery from anesthesia. More than half (58.3%) of patients improved, while 23.1% still experienced neurological dysfunctions, and 7.4% died.The present study is limited by the levels of evidence of the included studies. There is heterogeneity among cases with respect to patient demographics and medical history. Angiography is critical in assessing the presence and extent of underlying vascular diseases. Intracranial hemorrages may be caused by intraoperative or postoperative cerebrospinal fluid leakage that will lead to intracranial pressure change and induced by intracranial venous or arterial bleeding. The treatment strategies include conservative medical management and surgical treatment. Individualized treatment should be emphasized.

BACKGROUND: Accurate preoperative puncture and localization is a key step in percutaneous endoscopic lumbar discectomy (PELD). This study investigated the benefit of puncture and localization for PELD by C-arm navigation over conventional methods. METHODS: Sixteen adult cadavers were randomly divided into two groups (group A defined as the C-arm navigation method, and group B defined as the conventional localization method). Two junior orthopedic surgeons who specialized in spinal surgeries were randomly allocated to each group. Conventional localization using C-arm fluoroscopy and localization using C-arm navigation were performed during the procedure. The intervertebral foramen on both sides at L3-L4, L4-L5, and L5-S1 levels were punctured using the two methods. Technical parameters, such as fluoroscopy time, puncture time, overall time taken for puncture and localization, as well as the number of fluoroscopies, number of puncture attempts, and success rate of the first puncture were compared between the two methods. The learning curves were plotted for the two methods, and correlations between all technical parameters were analyzed. RESULTS: Puncture and localization for PELD assisted by C-arm navigation had a flatter learning curve compared with the conventional localization method. The fluoroscopy, puncture, and total puncture-localization time for group A were 5.61 (±1.37), 2.29 (±1.22), and 9.78 (±2.66) minutes compared with 15.72 (±3.59), 4.87 (±1.70), and 20.59 (±4.79) minutes for group B, respectively (P

The eastward- and westward-traveling 10-day waves with zonal wavenumbers up to 6 from surface to the middle mesosphere during the recent 12 years from 2007 to 2018 are deduced from MERRA-2 data. On the basis of climatology study, the westward-propagating wave with zonal wave number 1 (W1) and eastward-propagating waves with zonal wave numbers 1 (E1) and 2 (E2) are identified as the dominant traveling ones. They are all active at mid- and high-latitudes above the troposphere and display notable month-to-month variations. The W1 and E2 waves are strong in the NH from December to March and in the SH from June to October, respectively, while the E1 wave is active in the SH from August to October and also in the NH from December to February. Further case study on E1 and E2 waves shows that their latitude–altitude structures are dependent on the transmission condition of the background atmosphere. The presence of these two waves in the stratosphere and mesosphere might have originated from the downward-propagating wave excited in the mesosphere by the mean flow instability, the upward-propagating wave from the troposphere, and/or in situ excited wave in the stratosphere. The two eastward waves can exert strong zonal forcing on the mean flow in the stratosphere and mesosphere in specific periods. Compared with E2 wave, the dramatic forcing from the E1 waves is located in the poleward regions.

By combining observations from three meteor radars and a mesosphere-stratosphere-troposphere radar arranged along the 120 degrees E meridian with reanalysis data from 20 February to 20 May 2015, we study the stratospheric final warming (SFW) in 2015 spring and planetary wave activities from the troposphere to the mesosphere and lower thermosphere (MLT) at different latitudes. There are two successive warming events with the polar mean temperature rises of 24 and 9 K at 10-hPa level. By means of the two warming events separated by only several days, the mean temperature increases by nearly 20 K, and the mean zonal wind decreases from more than 30 m/s to about -10 m/s; thus, seasonal transition of the polar circulation is completed. The investigation shows that the quasi 10- (Q10DW) and 16- (Q16DW)day waves occur around the SFW. In the troposphere, their amplitudes are close to 10 m/s in the wind field. At 10-hPa level of the stratosphere, the strong wave activities arise before the SFW, while in the MLT, the waves are amplified following the SFW with the amplitude peaks about 10 days after the SFW onset. The wave amplitude in the MLT tends to increase in the zonal wind but decrease in the meridional wind with decreasing latitude, which is roughly consistent with the Hough modes. Hence, the Q10DW and Q16DW in the MLT are distinct from those in the stratosphere, and they are likely to be generated and strengthened in situ in the upper stratosphere and MLT.

We demonstrate a sustainable and cost-effective route to fabricate high-sulfur-loading cathode materials with the cooperative interfaces of "sulfiphilic" and "lithiophilic" sites from the removal industry of the pollutant H

Although the characteristics of the traveling 10-day waves (10DWs) above the middle stratosphere have been well explored, little research has been performed on the counterpart in the troposphere and lower stratosphere (TLS). In the present study, we use radiosonde observations and MERRA-2 data from 2020 to characterize traveling 10DWs in mid-latitudes in the TLS. Single-site observations in both hemispheres show that strong 10DW activities are always accompanied by strong eastward jets (10–13 km). MERRA-2 data indicate that in the troposphere, the eastward-propagating modes with larger wavenumbers, i.e., E3, E4, E5 and E6 are dominant, while in the lower stratosphere, the eastward- and westward-propagating modes with small zonal wavenumbers, e.g., 1 and 2, are dominant. Further research on E3, E4, E5 and E6 modes in the troposphere of both hemispheres shows that all the wave activities are positively correlated to the background zonal wind. The refractive index squared reveals that a strong eastward jet is suitable for these four modes to propagate. However, just above the jet, the eastward wind decreases with altitude, and a thick evanescence region emerges above 15 km. E3, E4, E5 and E6 10DWs cannot propagate upward across the tropopause; as such, this can explain why these four modes are weak or even indiscernible in the stratosphere and above. In the troposphere, E5 10DW at 32° S was the most dominant mode in 2020. A case study of the anomalously strong E5 10DW activity on 12 May 2020 indicates that the wave amplification resulted from the upward and equatorward transmission of wave energy flows. Moreover, the tropopause and equatorial region can prevent the propagations of wave energy flows of E5 10DW. The upward-propagating wave energy is deposited near the tropopause, resulting in significant short-term variability in the tropopause height.

Improving tumor accumulation and delivery efficiency is an important goal of nanomedicine. Neutrophils play a vital role in both chemically mediating inflammatory response through myeloperoxidase (MPO) and biologically promoting metastasis during inflammation triggered by the primary tumor or environmental stimuli. Herein, a novel theranostic nanomedicine that targets both the chemical and biological functions of neutrophils in tumor is designed, facilitating the enhanced retention and sustained release of drug cargos for improved cancer theranostics. 5-hydroxytryptamine (5-HT) is equipped onto nanoparticles (NPs) loaded with photosensitizers and Zileuton (a leukotriene inhibitor) to obtain MPO and neutrophil targeting NPs, denoted as HZ-5 NPs. The MPO targeting property of 5-HT modified NPs is confirmed by noninvasive positron emission tomography imaging studies. Furthermore, photodynamic therapy is used to initiate the inflammatory response which further mediated the accumulation and retention of neutrophil targeting NPs in a breast cancer model. This design renders a greatly improved theranostic nanomedicine for efficient tumor suppression, and more importantly, inhibition of neutrophil-mediated lung metastasis via the sustained release of Zileuton. This work presents a novel strategy of targeting neutrophils for improved tumor theranostics, which may open up new avenues in designing nanomedicine through exploiting the tumor microenvironment.

Using meteor radar, radiosonde and digisonde observations and MERRA-2 reanalysis data from 12 August to 31 October 2006, we report a dynamical coupling from the tropical lower atmosphere to the mes...

Using observation data from the Beijing MST radar from December 2013 to November 2014, together with the MERRA data, the dominant planetary waves (PWs) in the lower atmosphere over Xianghe (117.00°E, 39.77°N), i.e., quasi-16-day and quasi-10-day oscillations, were identified and investigated. These two kinds of PWs displayed similar seasonal and height variations, indicating they may have similar generation sources and dissipation processes. For both of them, near the tropospheric jet, significant zonal amplitudes could be observed in winter and spring months; quasi-constant phase or partial vertical wavelength larger than 100 km was present in the zonal wind in December, March and April, indicating they were quasi vertical stasnding waves near the tropospheric jet. The calculated refractive indexes of these two PWs were significantly negative in the lower troposphere (3.5-5 km) and near the tropopause (15-20 km), and the resulted strong wave evanescence or even wave reflection could explain the observed quasi standing structure of these two PWs and height variations of their wind amplitudes. Their estimated zonal wavenumbers in every month both showed the prevailing eastward propagation. Furthermore, we investigated the impact of PWs on the background wind by E-P fluxes and divergences, which indicates that both the quasi-16-day and the quasi-10-day PWs, especially the latter, may contribute significantly to the construction and maintenance of the tropospheric jet. We also found that the tropospheric jet magnitude and height were both intensively modulated by the quasi-16-day and quasi-10-day PWs.