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Wind gusts are common environmental hazards that can damage buildings, bridges, aircraft, and cruise ships and interrupt electric power distribution, air traffic, waterway transport and port operations. Accurately predicting peak wind gusts in numerical models is essential for saving lives and preventing economic losses. This study investigates the climatology of peak wind gusts and their associated gust factors (GFs) using observations in the coastal and open ocean of the northern South China Sea (NSCS), where severe gust-producing weather occurs throughout the year. The stratified climatology demonstrates that the peak wind gust and GF vary with seasons and particularly with weather types. Based on the inversely proportional relationship between the GF and mean wind speed (MWS), a variety of GF models are constructed through least squares regression analysis. Peak gust speed (PGS) forecasts are obtained through the GF models by multiplying the GFs by observed wind speeds rather than forecasted wind speeds. The errors are thus entirely due to the representation of the GF models. The GF models are improved with weather-adaptive GFs, as evaluated by the stratified MWS. Nevertheless, these weather-adaptive GF models show negative bias for predicting stronger PGSs due to insufficient data representation of the extreme wind gusts. The evaluation of the above models provides insight into maximizing the performance of GF models. This study further proposes a stratified process for forecasting peak wind gusts for routine operations. [ABSTRACT FROM AUTHOR]

Chemical composition, an important quality index for perlite, has great influence on the expansion characteristics of perlite. At present, the component analysis of perlite is mainly traditional chemical methods such as capacity, weight, Spectrophotometry and Atomic Absorption Spectrometry. These methods are not only complicated, but it is also impossible to determine the analysis results of all target elements simultaneously. The X-ray Fluorescence Spectrometry (XRF) method for determining major elements of Si, Al, Fe, Ca, Mg, Ti, K and Na in perlite has been established with fusion sampling preparation and is described in this paper. The perlite samples were fused with lithium tetraborate-lithium metaborate (mass ratio of 67:33) as the fusing reagent, the mixed solvent dilution ratio was 1:10 and the fusing temperature was 1050℃. The results show that these experimental conditions satisfy the requirements of analysis and overcome the problem of lower measurement results of silicon due to uneven expansion when fusing perlite samples at high temperature. After the instrument parameters were optimized, working curves were established and the matrix effect was corrected by using various national standard materials and self-made perlite management samples. The determination values obtained by using the XRF method are in good agreement with those measured by traditional chemical methods. The method detection limit is lower than 0.05% and the method precision degree(RSD, n=12) is lower than 1.5%. Compared with classical analysis methods, the XRF method has many advantages such as high efficiency, is environmentally-friendly, has high precision and accuracy, and is simple to conduct. The results show that the major elements in perlite can be determined rapidly and simultaneously by the XRF method with one time fusion sampling preparation.

Macrophages are a double-edged sword with potential cancer-promoting and anticancer effects. Controversy remains regarding the effect of macrophages, especially M1 macrophages, on tumor promotion and suppression. We aimed to investigate the role of M1 macrophages in the occurrence and progression of esophageal squamous cell carcinoma (ESCC). Analyzing the data in Gene Expression Omnibus database by the CIBERSORT algorithm found that M1 macrophages were one of the important components of many immune cells in ESCCs, and the increase in their number was obviously negatively correlated with tumor T staging. This result was verified by our experimental data: the density of CD68/HLA-DR double-stained M1 macrophages in ESCC tumor nest and tumor stroma was significantly higher than that in cancer-adjacent normal (CAN) tissues. The density of M1 macrophages in ESCC tumor nest was negatively correlated with the patient's lymph node metastasis and clinical stage (P < 0.05), and the negative tendency was more obvious for M1 macrophages in ESCC tumor stroma (P < 0.001). Exposure to M1 macrophage-conditioned medium inhibited ESCC cell migration and invasion ability significantly (P < 0.05). Moreover, the increased M1 macrophage density in ESCC tumor stroma correlated positively with good prognosis of ESCC. M1 macrophages were involved in inhibiting ESCC cell migration and invasion, which could serve as a good prognostic factor in patients with ESCC. [ABSTRACT FROM AUTHOR]

To investigate the values of 10-m drag coefficient (CD) in different coastal areas under the influence of tropical cyclones, the present study used the observational data from four towers in different coastal areas of the South China Sea (SCS) during six tropical cyclone (TC) passages, and employed the eddy covariance method and the flux profile method. The analysis of footprint showed that the fluxes at Zhizai Island (ZZI), Sanjiao Island (SJI) and Donghai Island (DHI) were influenced basically by the ocean, and the flux at Shangyang Town (SYT) was influenced mainly by the land. The results showed that the dependence relationships of CD on 10-m wind speed (U10) in four different coastal areas under the influence of TCs were different. CD at ZZI and SJI initially increased and then decreased as U10 increased, similar to the pattern over the ocean. CD at ZZI and SJI represented the values over shallow water with seawater depths of ~7 m and ~2 m, respectively. Moreover, the critical wind speed at which CD peaked gradually decreased as the seawater depth became shallower in the coastal areas. CD at DHI and SYT decreased monotonously as U10 increased, similar to the pattern over the land. CD at DHI represented the value over the transition zone from shallow water to coastal land, and CD at SYT represented the value over the coastal land. Meanwhile, the eddy covariance method and the flux profile method were compared at ZZI and SYT during TC passages. It was found that their CD values obtained by the two methods were close. Finally, the parameterizations of observed u* and CD as a function of U10 over four different coastal areas were given under the influence of high winds. These parameterizations of observed CD may be used in high-resolution numerical models for landfalling TC forecast. [ABSTRACT FROM AUTHOR]

Background: Immunosuppressant non-adherence is a widespread problem among solid organ recipients. With the newly published clinical trials, the randomized controlled trials (RCTs) based systematic review of adherence-enhancing interventions on immunosuppressant adherence in solid organ recipients has not been completed. In this systematic review and meta-analysis, we compared the efficacy of adherence-enhancing interventions versus routine intervention, as performed with RCTs, on immunosuppressant adherence in solid organ transplantation recipients. Methods: PubMed, Embase, Cochrane Library, CINAHL full text, and PsycINFO were searched from database inception to December 2019. This review was conducted following the PRISMA's reporting guidelines and according to the principles recommended by Cochrane Handbook for Systematic Review. Results: The search yielded 10,479 articles. A total of 27 articles (26 studies) with 715 participants were included in our analysis. Results from the meta-analysis revealed that as compared with that of the routine intervention group, the rates of overall adherence, dosing adherence, and timing adherence were significantly increased within the adherence-enhancing intervention group, with the pooled risk ratio (RR) of overall adherence = 1.17, [95% confidence interval (CI): 1.07 to 1.28; p = 0.0006]; RR of dosing adherence = 1.21 (95% CI: 1.08 to 1.36, p = 0.001); RR of timing adherence = 1.16 (95% CI: 1.03 to 1.29, p = 0.01). There was a significantly increased adherence score in the adherence-enhancing intervention group; however, no statistical significance on the immunosuppressant blood concentration was found between the two study groups. Results obtained from a subgroup analysis shown interventions led by a multidisciplinary team, both the assessment time at 6 months and 12 months demonstrated a significantly increased adherence rate in the intervention group compared with the control group. Conclusions: The findings of this report indicate that clinicians (doctors and nurses) should maintain a long-term intervention protocol to ensure immunosuppressant adherence within solid organ transplant recipients. To accomplish this goal, we recommend a multidisciplinary team-led, comprehensive intervention approach combined with mobile health monitoring for the administration of an effective immunosuppressive therapy regimen. [ABSTRACT FROM AUTHOR]

Following previous studies of the rainfall forecast in Shenzhen owing to landfalling tropical cyclones (TCs), a nonparametric statistical scheme based on the classification of the landfalling TCs is applied to analyze and forecast the rainfall induced by landfalling TCs in the coastal area of Guangdong province, China. All the TCs landfalling with the distance less than 700 kilometers to the 8 coastal stations in Guangdong province during 1950-2013 are categorized according to their landfalling position and intensity. The daily rainfall records of all the 8 meteorological stations are obtained and analyzed. The maximum daily rainfall and the maximum 3 days'accumulated rainfall at the 8 coastal stations induced by each category of TCs during the TC landfall period (a couple of days before and after TC landfalling time) from 1950 to 2013 are computed by the percentile estimation and illustrated by boxplots. These boxplots can be used to estimate the rainfall induced by landfalling TC of the same category in the future. The statistical boxplot scheme is further coupled with the model outputs from the European Centre for Medium-Range Weather Forecasts (ECMWF) to predict the rainfall induced by landfalling TCs along the coastal area. The TCs landfalling in south China from 2014 to 2017 and the corresponding rainfall at the 8 stations area are used to evaluate the performance of these boxplots and coupled boxplots schemes. Results show that the statistical boxplots scheme and coupled boxplots scheme can perform better than ECMWF model in the operational rainfall forecast along the coastal area in south China. [ABSTRACT FROM AUTHOR]

The co‐factors independent cypridina bioluminescence was often used to detect molecular oxygen. Whereas the native cypridina oxyluciferin and the majority analogues only emit blue light, it limits the application of the cypridina oxyluciferin derivative in detection active oxygen species. To overcome these limitations, we design two series of oxyluciferin derivatives: 2‐acetamido‐5‐aryl‐3‐(p‐trifluoromethylphenyl)pyrazine and 2‐acetamido‐5‐aryl‐3‐(p‐methoxylphenyl)pyrazine. The results found that the fluorescence emissions of the cypridina oxyluciferin derivatives cover the whole region of visible light. Especially, 2‐acetamido‐5‐(trans‐2,3,6,7‐tetrahydro‐1H,5H‐benzo[i,j]quinolizine‐ethenyl)‐3‐(p‐trifluoromethyl phenyl)pyrazine (1 h) can emit red light. By comparison of the emission spectra and oscillator strengths, it found that electron‐donating group in C3 position contributed to blue shift wavelength and improve luminous efficiency. The increasing conjugated length by introducing a conjugated double bond made the emission spectra shift to red and the luminescence strengths much stronger. Moreover, the analysis of the relative stabilities at the ground and excited states indicates that neutral forms, not amide ions, are dominant at physiological pH. [ABSTRACT FROM AUTHOR]

Aim: To explore the association between the determinant factors including HLA-DQB1*03, DRB1-*07, -*13 and high-risk HPV infection, the cervical squamous cell carcinoma (CSCC) pathogenesis among Chinese Uighur and Han population.Materials& Methods: HLA alleles were genotyped by PCR sequence-specific primers.Results: HPV16 infection rate was significantly higher among the Uighurs and Hans with CSCC as compared with healthy controls, respectively. HLA-DQB1*03 significantly increased among Uighurs with CSCC, while HLA-DRB1*07 significantly increased among Hans with CSCC. Similar tendencies were observed for DQB1*03 with HPV16-positive Uighurs CSCC and DRB1*07 with HPV16-positive Hans CSCC.Conclusion: This study suggests that HLA-DQB1*03 and DRB1*07 alleles may influence the immune response to HPV16 infection and increase the risk of CSCC among the Uighurs and Hans in China. [ABSTRACT FROM AUTHOR]

Summary: Synovial sarcoma (SS) is a mesenchymal malignant neoplasm showing characteristics of epithelial–mesenchymal biphasic differentiation. SS is of uncertain cellular origin; however, studies have suggested that SS originates from a somatic stem cell population. In this study, we aim to determine whether differential morphological features of the epithelial–mesenchymal transition (EMT) contributed to the tumourigenesis of SS invasion and metastasis. Twelve paraffin‐embedded formalin‐fixed tissue (FFPE) SS tissue specimens were obtained, and laser capture microdissection (LCM) with the ArcturusXT system and small chip method (SCM) were used to isolate and purify spindle and epithelial cells from SS specimens. The TRIzol method was used to extract RNA, and the mRNA levels of EMT‐related genes in epithelial and spindle cells of SS specimens were measured using real‐time fluorescent quantitative reverse transcription polymerase chain reaction (qRT‐PCR). The results show that collection of about 2 × 104 cells from FFPE samples using LCM was sufficient for qRT‐PCR, with an efficiency of 75%. Compared with LCM, 72.2% (13 of 18) RNA samples were successfully extracted using SCM to isolate cells from FFPE SS tissues. In the 16 samples (11 spindle cell samples and 5 epithelial cell samples), Snail mRNA was significantly upregulated in spindle cell areas compared with that in epithelial cell areas (P = .001). Expression levels of the epithelial marker E‐cadherin and the mesenchymal marker N‐cadherin were not significantly different between epithelial and spindle cell areas. In spindle cells of recurrent SS samples, the mRNA levels of E‐cadherin, N‐cadherin, Snail, and Slug were higher in primary SS samples than in recurrent samples. Taken together, our results indicated that in SS samples, Snail mRNA was upregulated in spindle cell areas compared with that in epithelial cell areas and that the expression of EMT‐related genes was increased in primary SS. LCM could be used to isolate and purify RNA from FFPE samples. [ABSTRACT FROM AUTHOR]

This paper investigates processing of fast-response data and corrections of turbulent fluxes obtained by using eddy covariance method based on data collected at an offshore observation tower during three Coldintrusion (CI) events in the South China Sea in 2010. This study presents the data processing procedure in detail and compares frictional velocities (u*), sensible heat fluxes (H) and latent heat fluxes (LE) yielded by using different averaging periods and different coordinate rotation methods; evaluates the sonic temperature correction for sensible heat flux and the Webb correction for latent heat flux as a function of 10 m wind speed (u10) during the CIs. The results show (1) that the different averaging periods of 30 min and 10 min cause biases of u*(H,LE) within 5% (15%, 62%). The values of u(u* H,LE) averaged from 30 mins are mostly larger than those averaged from 10 mins. We suggest that the averaging period of 10 min is not sufficiently long to capture all scale eddies and recommend 30 min averaging period in calculating turbulent fluxes using eddy covariance method during CIs; (2) that the values of u*(H,LE) obtained from double rotation (DR2) and those obtained from planar fit rotation (PF) have good agreements and correlation coefficients between them are larger than 0.99. BecausePF method requires unchanged environment and it is easier to applyDR2 method, we suggestDR2 coordinate rotation method in processing fast-response data; and (3) that the median values of frictional velocity (sensible heat flux and latent heat flux) binned according to 2 m s-1 intervals of u10 increase (decrease, increase) by less than 9% (4%, 10%) by Coriolis corrections (sonic temperature corrections, Webb corrections), which decreases (decreases, increases) with increasing u10when u10are 5-17 m s-1. [ABSTRACT FROM AUTHOR]

Because of its high fluorescence quantum yield, high sensitivity and high signal-to-noise ratio, firefly oxyluciferin is widely used in the field of fluorescent probe. However, there are six chemical forms which can possibly co-existence in solution. Reliable relative stability of the different forms in solution made the analysis of their photophysical properties difficult. In order to address this issue and gain insights into the nature of spectra feature observed in the experiments, we designed six oxyluciferin derivatives. The distribution of the species at the ground and excited states demonstrate that only keto(0), keto(−1) and enol(−2) are present for all oxyluciferin derivatives. The majority of molecules are surprisingly more acidic at the ground state than at the excited state, which indicate that they are photobases. The distribution of the species at the excited state indicate that the most pH-sensitive molecules are 2-(6′-hydroxybenzothiazol-2-yl)-2,3-dihydro-4-hydroxypyrrole (Oxyan-1) and 1-(5′-brominated-6′-hydroxybenzothiazol-2-yl)-2-(4-hydroxythiazole) ethylene (Oxyan-4), as their chemical equilibria consist on the same three species: keto(0), keto(−1) and enol(−2). While the first deprotonation occurs at acidic pH, the second occurs at basic pH, with a single deprotonated species existing at more neutral pH. This indicates that both Oxyan-1 and Oxyan-4 can be good candidates for fluorescent pH probing. Exhaustive analyses of the emission spectra in water revealed that the firefly OxyLH 2 analogues can emit in the UV–visible and near-infrared wavelength range. [ABSTRACT FROM AUTHOR]

Benzothienobenzothiophene (BTBT) liquid-crystalline semiconductors are arousing a lot of interest due to their long-range ordered, self-organizational abilities and high-charge carrier transport properties. In this work, we report the design and the straightforward synthesis of a homologous series of compounds containing the BTBT substructure by the successive Suzuki cross-coupling and FeCl3 oxidative Scholl cyclodehydrogenation reaction. Target π-conjugated aromatic, H-shaped sanidic mesogens self-organize into a classical hexagonal columnar mesophase over wide temperature ranges as deduced from polarized optical microscopy (POM), differential scanning calorimetry (DSC), and small-angle X-ray scattering (SAXS) investigations. UV/Vis absorption and photoluminescence spectra, measured in both solution and films, revealed strong photoluminescence with high quantum yields. The charge carrier mobility measured by the time-of-flight (TOF) technique showed a balanced ambipolar hole and electron mobility in the range of 10−3 cm2 V−1 s−1 between 100 and 230 °C in the mesophase. These BTBT-based columnar liquid crystals may represent attractive candidates to be incorporated within one-dimensional organic optoelectronic devices. [ABSTRACT FROM AUTHOR]

Based on observed rainfall data, this study makes a composite analysis of rainfall asymmetry in tropical cyclones (TCs) after making landfall in Guangdong province (GD) during 1998-2015. There are 3.0 TCs per year on average making landfall in GD and west of GD (WGD) has the most landfall TCs. Most of TCs make landfall in June, July, August, and September at the intensities of TY, STS, and TS. On average, there is more rainfall in the southwest quadrant of TC in CGD (center of GD), WGD, and GD as a whole, and the maximum rainfall is located in the southwest near the TC center. The mean TC rainfall in the east of GD (EGD) leans to the eastern side of TC. The TC rainfall distributions in June, July, August, and September all lean to the southwest quadrant and the maximum rainfall is located in the southwest near the TC center. The same features are found in the mean rainfall of TD, TS, STS, TY, and STY. The maximum rainfall is mainly in the downshear of vertical wind shear. Vertical wind shear is probably the dominate factor that determines asymmetric rainfall distribution of TCs in GD. Storm motion has little connection with TC rainfall asymmetry in GD. [ABSTRACT FROM AUTHOR]

This study uses numerical simulations to examine a case of sea fog that was observed from 20 to 22 March 2011 on the southern China coast. The observation dataset includes observatory data, cloud-top temperature from MODIS, GPS sonde, and data from the Integrated Observation Platform for Marine Meteorology (IOPMM). The simulations are based on the Weather Research and Forecasting (WRF) model with four distinct parameter settings. Both the observations and simulations focus on the characteristics of the fog extent, boundary layer structure, and meteorological elements near the air-sea interface. Our main results are as follows: (1) The extent of mesoscale sea fog can be well simulated when the sea surface temperature has at least 0.5x0.5 horizontal resolution. (2) To accurately model the vertical structure of the sea fog, particularly the surface-based inversion, vertical levels must be added in the boundary layer. (3) When these model conditions are met, the simulations faithfully reproduce the measured downward shortwave radiation, downward longwave radiation, and surface sensible heat flux during the sea fog period. [ABSTRACT FROM AUTHOR]

Large-scale integration of renewable energy resources in the Alternating Current (AC) grids will have a serious impact on power system operation. The development of the Direct Current (DC) is presented as a solution to overcome some of the negative impacts on massive micro-generation deployment. Over 100 years later, from the time when AC was proving superior over DC, the existing AC electric power grids, equipment, and transmission method facing a big challenge from DC. In this paper, what has changed since Edison and Westinghouse public battle are firstly discussed? Then the high voltage DC (HVDC) transmission system is depicted the developmental history and the system׳s structure, and the HVDC applications based on voltage-source converters (VSCs) combined with the renewable generation are introduced, such as onshore, offshore wind, and City Power Supply. Then, those key technologies are represented. Finally, how to build future electricity grid network and VSCs-HVDC may improve the world is explored, and some recommendations are proposed. [ABSTRACT FROM AUTHOR]