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Using multiple observations such as S-band radar (SPOL) in Shijiazhuang, X-band phased array radar (XPAR) in Xiong'an, and ground-based encrypted automatic stations, detection features and evolutions of EF2 tornado at Donglü Village, Qingyuan District of Baoding City Hebei Province on 21 July 2021 are studied. The tornado occurred within the center of high dew point values and in an area characterized by a significant temperature gradient. There are convergence lines within the center of high dew point temperatures and a temperature gradient zone. From perspectives of environmental conditions such as convective available potential energy (CAPE), 0-6 km vertical wind shear, and the lifting condensation level (LCL), there is a possibility for tornado occurrence. It is evident that the tornado formed within a low-vortex precipitation cloud system, showing significant divergence at high altitudes. The subsequent storm propagation leads to multiple single-cell mergers and a supercell formation. A significant reflectivity factor core moving from southeast to northwest is observed at the top of hook echo, corresponding to the tornado location. Both SPOL and XPAR detected continuous mesocyclones on average radial velocity images, with dimensions ranging from 1.4 to 4.2 km, and rotating speeds of 10-20 m·s-1, indicating weak mesocyclones with short durations (30-35 min). During tornado development, a decrease in the lower angle detection of adjacent rotational speed pairs coincides with mesocyclone downward extension to 1.2-1.4 km and its diameter shrinking to 0.8-1 km, indicating tornado formation. Tornado storm parameters show maximum rotation speed and vorticity at low levels, promoting its intensification. Compared with XPAR storm parameters, SPOL features a larger maximum reflectivity factor (noless than 55 dBZ) and a greater distribution height (8-10 km). The consistency of SPOL and XPAR in detecting the tornado location, radial velocity, and storm diameter is compared. On the radar radial velocity image, there are pairs of positive and negative velocity values arranged symmetrically along the radial direction. The echo top of XPAR radar is approximately 6 km higher than that of SPOL radar, and the peak time of XPAR echo coincides with the storm's appearance. The tornado vortex signature (TVS) reaches its strongest period from 1536 BT to 1542 BT, extending vertically up to 2-4 km.

In order to enhance the understanding of rainfall observation performance of micro-smart (integrated) weather stations and to promote the application in rainfall observation operations, a comparative experiment for the rainfall observation of radar, photoelectric, piezoelectric and tipping bucket micro-smart weather stations is carried out by Hebei Xiong'an New Area Meteorological Service from June to November in 2021. The rainfall observation capability of micro-smart weather stations with different rainfall observation principles are analyzed in terms of total rainfall, rainfall intensity, percentage of rainfall intensity and temporal characteristics. It shows that when the accumulated precipitation exceeds 10 mm, the precipitation measured by the tipping bucket micro-smart weather station can meet observation error control requirements compared with the precipitation observed by the standard station, while results of the radar micro-smart weather station are large and results of the photoelectric and piezoelectric micro-smart weather stations are small. When the cumulative precipitation is less than 10 mm, results of the tipping bucket and piezoelectric micro-smart weather stations can meet observation error control requirements, while results of radar micro-smart weather stations are large and results of photoelectric micro-smart weather stations are small. In terms of rainfall intensity, the double tipping bucket station is suitable for monitoring rainfall extreme, while photovoltaic and piezoelectric stations underestimate the extreme. Radar-based micro-smart weather stations can be calibrated and revised for rainfall extreme monitoring by adjusting internal parameters. Analysis of different rainfall intensities and their corresponding rainfall ratios show that the rain intensity corresponding to a rain intensity accumulation ratio greater than 95% at each micro-smart weather station is[0.3 mm·min-1, 0.6 mm·min-1] and the rain intensity corresponding to a rainfall accumulation ratio greater than 50% is[0.1 mm·min-1, 0.4 mm·min-1]. It shows that within 0.4 mm·min-1, the proportion of rainfall measured by any type of rain sensor accounts for more than half of the total rainfall, so more attention should be paid to accuracy for small rain intensity in the operational rain sensor rate determination. As the resolving capacity increases, the tipping bucket type micro-smart weather station becomes less sensitive to the starting time and will identify the ending time earlier. The radar type micro-smart weather station responds to rainfall relatively more quickly. Finer resolving capacity of the rain sensor will enhance the monitoring effectiveness of fine rainfall and the effective rainfall rate.

The complexity of aerosol particle properties and the diversity of characterizations make aerosol vertical transport flux measurements and analysis difficult. Although there are different methods, such as aerosol particle number concentration flux and aerosol mass flux based on the eddy covariance principle as well as aerosol mass flux measurements based on the light-propagated large-aperture scintillation principle, there is a lack of mutual validation among the different methods. In this paper, a comparison of aerosol mass flux measurements based on the eddy covariance principle and aerosol mass flux measurements based on the light-propagated large-aperture scintillation principle is carried out. The key idea of aerosol mass flux measurements based on the light-propagated large-aperture scintillation principle is the determination of the imaginary part of the atmospheric equivalent refractive index structure parameter (AERISP). In this paper, we first compare the AERISPs measured by two different methods and then compare the aerosol mass vertical transport fluxes obtained by different methods. The experiments were conducted on the campus of the University of Science and Technology of China (USTC). A light propagation experiment was carried out between two tall buildings to obtain the imaginary and real parts of the AERISPs for the whole path, which in turn can be used to obtain the aerosol vertical transport flux. An updated visibility meter is installed on the meteorological tower in the middle of the light path, which is utilized to obtain the single-point visibility, which is then converted to the imaginary part of the atmospheric equivalent refractive index (AERI). The imaginary parts of the AERISP were obtained via spectral analysis with visibility data. The results show that the imaginary parts of the AERISPs obtained by different methods are in good agreement. The imaginary part of the AERI measured by the visibility meter and the vertical wind speed obtained by the ultrasonic anemometer were used for covariance calculations to obtain the aerosol vertical transport flux. The trends in aerosol vertical transport fluxes obtained by the different methods are consistent, and there are differences in some details, which may be caused by the inhomogeneity in the vertical transport of aerosol fluxes. The experimental results also showed that urban green land is a sink area for aerosol particles. [ABSTRACT FROM AUTHOR]

The complexity of aerosol particle properties and the diversity of characterizations make aerosol vertical transport flux measurements and analysis difficult. Although there are different methods, such as aerosol particle number concentration flux and aerosol mass flux based on the eddy covariance principle, and aerosol mass flux measurements based on the light-propagated large-aperture scintillation principle, there is a lack of mutual validation among the different methods. In this paper, a comparison of aerosol mass flux measurements based on the eddy covariance principle and aerosol mass flux measurements based on the light-propagated large aperture scintillation principle is carried out. The key idea of aerosol mass flux measurements based on the light-propagated large-aperture scintillation principle is the determination of the imaginary part of the atmospheric equivalent refractive index structure parameter (AERISP). In this paper, we will first compare the AERISPs measured by two different methods and then compare the aerosol mass vertical transport fluxes obtained by different methods. The experiments were conducted on the campus of the University of Science and Technology of China (USTC). The light propagation experiment was carried out between two tall buildings to obtain the imaginary and real parts of AERISPs for the whole path, which in turn can be used to obtain the aerosol vertical transport flux. An updated visibility meter is installed on the meteorological tower in the middle of the light path, which is utilized to obtain the single-point visibility, which is then converted to the imaginary part of the atmospheric equivalent refractive index (AERI). The imaginary parts of the AERISP were obtained using spectral analysis with visibility data. The results show that the imaginary parts of the AERISPs obtained by different methods are in good agreement. The imaginary part of the AERI measured by the visibility meter and the vertical wind speed obtained by the ultrasonic anemometer were used for covariance calculation to obtain the aerosol vertical transport flux. The trends of aerosol vertical transport fluxes obtained by different methods are consistent, and there are differences in some details, which may be caused by the inhomogeneity of the vertical transport of aerosol fluxes. The experimental results also show that urban green land is a sink area for aerosol particles. [ABSTRACT FROM AUTHOR]

Urban green and blue infrastructure (GBI) is effective in urban heat mitigation. However, the diurnal variations in the thermal regulation of GBI on different types of urban pedestrian walkways in the subtropical humid climate zone are unclear. Based on traverse measurements in January 2022, this study investigates how outdoor air temperature (Ta) and wet-bulb temperature (Tw) at the pedestrian level are affected by various urban morphology and GBI characteristics in the central urbanized area of Guangzhou (China). Six building-related, three vegetation-related, and three water-related parameters were applied in the analyses. Results show that green infrastructure (GI) has the strongest cooling effect (Pearson's coefficient r = −0.33~−0.54) on Ta on cloudy evenings and the weakest cooling effect (r = −0.22~−0.32) on clear evenings. Blue infrastructure (BI) exhibits the highest correlations with the cooling effect for Ta on clear afternoons (r = −0.35~−0.51) and weaker, but more consistent, correlations throughout cloudy days (r = −0.23~−0.43). Strong correlations between GI and Tw cooling are observed in the morning and evening on clear days (r = −0.13~−0.48), while BI exhibits the strongest correlation with Tw cooling on clear afternoons (r = −0.13~−0.37). In addition, both GI and BI show a greater cooling effect on both Ta and Tw in low-rise areas compared to high-rise areas. Compared to the individual GI or BI, the integrated GBI has a higher cooling intensity for both Ta and Tw in high-rise areas. However, the cooling potential of integrated GBI is slightly lower for both Ta and Tw during noon and afternoon in low-rise areas. The findings of this study give insights into urban GBI planning and design of specific urban microclimate regulation strategies. [ABSTRACT FROM AUTHOR]

Genistein (Gen) has shown protective effects against ageing process. To explore the role of Gen on the senescence of H2O2-induced human umbilical vein endothelial cells (HUVECs) and investigate the possible mechanism. HUVECs were treated with different concentrations of H2O2 (50, 100, 200 and 400 μmol/L) for 1 h or Gen administration (20, 40, 80 and 160 μg/mL) for 24 h. Functional experiments (cell counting kit-8, β-galactosidase staining and flow cytometry) were used to detect the effect of Gen on H2O2-induced HUVECs. After HUVECs were transfected with TXNIP overexpression plasmids, the expression of p16, p21, thioredoxin-interacting protein (TXNIP), nucleotide-binding and oligomerization domain-like receptor 3 (NLRP3), cleaved caspase-3 and cleaved caspase-1 in HUVECs were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. H2O2 (200 and 400 μmol/L) inhibited the proliferation of HUVECs. At concentrations of >50 μmol/L, H2O2 induced the cell cycle progression arrests in G1 phase and promoted cell senescence of HUVECs. Gen had no obvious cytotoxicity to HUVECs below 160 µg/mL. H2O2-induced HUVEC senescence and the expression of TXNIP and NLRP3 in HUVECs were down-regulated by Gen (40 and 80 µg/mL). Expressions of TXNIP and NLRP3 in HUVECs were up-regulated by H2O2 but down-regulated by Gen. Overexpressed TXNIP partially reversed the suppressive effect of Gen on H2O2-induced senescence and apoptosis of HUVECs. Expressions of p16, p21, TXNIP, NLRP3, cleaved caspase-3 and cleaved caspase-1 in H2O2-treated HUVECs were inhibited by Gen, while the inhibition as such was partially reversed by overexpressed TXNIP. H2O2-induced HUVEC senescence was alleviated by Gen via suppressing the TXNIP/NLRP3 axis, which may offer a potential therapeutic approach for improving HUVEC senescence and provide a new direction for the treatment of cardiovascular disease. [ABSTRACT FROM AUTHOR]

Summary: Vertebrate eye development and homoeostasis critically depend on the regulation of proliferation of cells forming the retinal pigment epithelium (RPE). Previous results indicated that the death‐associated protein like‐1 DAPL1 cell autonomously suppresses RPE proliferation in vivo and in vitro. Here, we show in human RPE cell lines that the pigment cell transcription factor MITF regulates RPE cell proliferation by upregulating DAPL1 expression. DAPL1 regulation by MITF is, however, mediated predominantly by (−) MITF, one of two alternative splice isoforms of MITF that lacks six residues located upstream of the DNA‐binding basic domain. Furthermore, we find that the regulation of DAPL1 by MITF is indirect in that (−) MITF stimulates the transcription of Musashi homolog‐2 (MSI2), which negatively regulates the processing of the anti‐DAPL1 microRNA miR‐7. Our results provide molecular insights into the regulation of RPE cell proliferation and quiescence and may help us understand the mechanisms of normal RPE maintenance and of eye diseases associated with either RPE hyperproliferation or the lack of regenerative proliferation. [ABSTRACT FROM AUTHOR]

Chlorogenic acid (CGA), derived from dicotyledons and ferns, has been demonstrated with anti-inflammatory, anti-bacterial, and free radical-scavenging effects and can be used to treat pulmonary fibrosis (PF). However, the specific mechanism by which CGA treats PF needs to be further investigated. In this study, in vivo experiment was firstly performed to evaluate the effects of CGA on epithelial-mesenchymal transition (EMT) and autophagy in bleomycin (BLM)-induced PF mice. Then, the effects of CGA on EMT and autophagy was assessed using transforming growth factor beta (TGF-β) 1-induced EMT model in vitro. Furthermore, autophagy inhibitor (3-methyladenine) was used to verify that the inhibitory mechanism of CGA on EMT was associated with activating autophagy. Our results found that 60 mg/kg of CGA treatment significantly ameliorated lung inflammation and fibrosis in mice with BLM-induced PF. Besides, CGA inhibited EMT and promoted autophagy in mice with PF. In vitro studies also demonstrated that 50 µM of CGA treatment inhibited EMT and induced autophagy related factors in TGF-β1-induced EMT cell model. Moreover, the inhibitory effect of CGA on autophagy and EMT in vitro was abolished after using autophagy inhibitor. In conclusion, CGA could inhibit EMT to treat BLM-induced PF in mice through, activating autophagy.

Context: Genistein (Gen) has shown protective effects against ageing process., Objective: To explore the role of Gen on the senescence of H 2 O 2 -induced human umbilical vein endothelial cells (HUVECs) and investigate the possible mechanism., Materials and Methods: HUVECs were treated with different concentrations of H 2 O 2 (50, 100, 200 and 400 μmol/L) for 1 h or Gen administration (20, 40, 80 and 160 μg/mL) for 24 h. Functional experiments (cell counting kit-8, β-galactosidase staining and flow cytometry) were used to detect the effect of Gen on H 2 O 2 -induced HUVECs. After HUVECs were transfected with TXNIP overexpression plasmids, the expression of p16, p21, thioredoxin-interacting protein (TXNIP), nucleotide-binding and oligomerization domain-like receptor 3 (NLRP3), cleaved caspase-3 and cleaved caspase-1 in HUVECs were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot., Results: H 2 O 2 (200 and 400 μmol/L) inhibited the proliferation of HUVECs. At concentrations of >50 μmol/L, H 2 O 2 induced the cell cycle progression arrests in G1 phase and promoted cell senescence of HUVECs. Gen had no obvious cytotoxicity to HUVECs below 160 µg/mL. H 2 O 2 -induced HUVEC senescence and the expression of TXNIP and NLRP3 in HUVECs were down-regulated by Gen (40 and 80 µg/mL). Expressions of TXNIP and NLRP3 in HUVECs were up-regulated by H 2 O 2 but down-regulated by Gen. Overexpressed TXNIP partially reversed the suppressive effect of Gen on H 2 O 2 -induced senescence and apoptosis of HUVECs. Expressions of p16, p21, TXNIP, NLRP3, cleaved caspase-3 and cleaved caspase-1 in H 2 O 2 -treated HUVECs were inhibited by Gen, while the inhibition as such was partially reversed by overexpressed TXNIP., Discussion and Conclusions: H 2 O 2 -induced HUVEC senescence was alleviated by Gen via suppressing the TXNIP/NLRP3 axis, which may offer a potential therapeutic approach for improving HUVEC senescence and provide a new direction for the treatment of cardiovascular disease.

Objective : To explore the effects of interventional therapy (IT) on Aquaporin-4 (AQP4) gene expression and neuron apoptosis in rabbits with ischemic brain injury caused by carotid artery stenosis, and to further optimize the therapeutic regime of clinical ischemic brain injury (IBI). Methods : 30 New Zealand rabbits were randomly divided into three groups: Sham group (n=10), IBI group (n=10) and IBI+IT group (n=10). A rabbit model of carotid artery stenosis was established to induce IBI. 12 hours later, interventional therapy was achieved through percutaneous transluminal coronary angioplasty (PTCA) by pumping up the balloon to widen the catheter. The expression of AQP4 mRNA and protein were determined by reverse transcription polymerase chain reaction (RT-PCR) and western blot, respectively. The distributions of rabbit hippocampus and cerebral cortex were detected by Nissl staining. The neuronal function of rabbits in the three groups after surgery was assessed with mNSS score. TUNEL (Terminal Transferase-mediated dUTP Nick End-labelling) staining was used to observe neuron apoptosis in rabbit brain tissue. The expressions of Bax and Bcl-2 protein were detected by western blot. Markers of oxidative stress in rabbit brain tissues were detected by Reactive Oxygen Species ELISA Kits. Morphology of the organelles in rabbit brain tissues was observed with transmission electron microscopy (TEM). Results : The protein and mRNA expressions of AQP4 in rabbit brain tissues were significantly decreased in the IBI group. Nissl staining results showed that IT improved IBI in rabbit hippocampus. In addition, IT significantly ameliorated the neuronal function of rabbits, and reduced the apoptosis and oxidative stress level of neurons in brain tissues. Furthermore, we found that after IT, organelle damage was significantly reduced in rabbit neurons. Conclusion : After receiving IT, AQP4 gene level and neuron apoptosis were significantly reduced in rabbit brain tissues with ischemic brain injury from carotid artery stenosis., Competing Interests: None., (IJCEP Copyright © 2021.)