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Top-down atmospheric inversion infers surface–atmosphere fluxes from spatially distributed observations of atmospheric composition in order to quantify anthropogenic and natural emissions. In this study, we developed a Regional multi-Air Pollutant Assimilation System (RAPAS v1.0) based on the Weather Research and Forecasting–Community Multiscale Air Quality (WRF–CMAQ) modeling system model, the three-dimensional variational (3D-Var) algorithm, and the ensemble square root filter (EnSRF) algorithm. This system can simultaneously assimilate hourly in situ CO, SO 2 , NO 2 , PM 2.5 , and PM 10 observations to infer gridded emissions of CO, SO 2 , NO x , primary PM 2.5 (PPM 2.5), and coarse PM 10 (PMC) on a regional scale. In each data assimilation window, we use a "two-step" scheme, in which the emissions are inferred first and then input into the CMAQ model to simulate initial conditions (ICs) of the next window. The posterior emissions are then transferred to the next window as prior emissions, and the original emission inventory is only used in the first window. Additionally, a "super-observation" approach is implemented to decrease the computational costs, observation error correlations, and influence of representative errors. Using this system, we estimated the emissions of CO, SO 2 , NO x , PPM 2.5 , and PMC in December and July 2016 over China using nationwide surface observations. The results show that compared to the prior emissions (2016 Multi-resolution Emission Inventory for China – MEIC 2016)), the posterior emissions of CO, SO 2 , NO x , PPM 2.5 , and PMC in December 2016 increased by 129 %, 20 %, 5 %, 95 %, and 1045 %, respectively, and the emission uncertainties decreased by 44 %, 45 %, 34 %, 52 %, and 56 %, respectively. With the inverted emissions, the RMSE of simulated concentrations decreased by 40 %–56 %. Sensitivity tests were conducted with different prior emissions, prior uncertainties, and observation errors. The results showed that the two-step scheme employed in RAPAS is robust in estimating emissions using nationwide surface observations over China. This study offers a useful tool for accurately quantifying multi-species anthropogenic emissions at large scales and in near-real time. [ABSTRACT FROM AUTHOR]

Many important engineering systems can be classified as Euler–Lagrange (EL) systems. In this work we develop a new Proportional‐Integral‐Derivative (PID) ‐based tracking control solution for uncertain EL systems subject to actuation failures and saturation. Two set of control algorithms are developed using robust adaptive and neuroadaptive methods, which are shown to exhibit several salient features: (1) the control schemes are of PID form, hence is characterized with simplicity in structure and intuition in concept; (2) the PID gains in the scheme are automatically updated by analytic algorithms with no need for manual tuning, rendering the control scheme more user‐friendly; and (3) the developed control algorithms are robust against nonvanishing disturbances, adaptive to unknown virtual parameter and immune to partial actuation effectiveness faults. [ABSTRACT FROM AUTHOR]

In this paper, Ho3+/Yb3+ co-doped Sodium Gadolinium Fluoride (NaGdF4) phosphors were synthesized by a facile and efficient hydrothermal method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy spectrum (EDS), and photoluminescence (PL). The results of XRD and SEM indicated that the prepared NaGdF4 samples have the hexagonal structure and good orientation in the case of changing the concentration of Yb3+. The results of pump power dependence of up-conversion intensity indicated that the energy transfer mechanism from Yb3+ to Ho3+ is a two-photon process. The energy transfer between Ho3+ and Yb3+ under 448 nm excitation was determined by PL spectra and fluorescence lifetimes. All the results proved that the doping of Yb3+ ions can effectively improve the up-conversion luminescence of NaGdF4 phosphors and achieve quantum cutting efficiency of up to 179.8%. Overall, NaGdF4:Ho3+/Yb3+ have potential application in the field of optoelectronic materials. [ABSTRACT FROM AUTHOR]

Fluoroquinolones are a kind of synthetic drugs commonly used in clinical treatment. They have good broad-spectrum antimicrobial properties. They are not only convenient to administer, but also have remarkable therapeutic effects. In this paper, we selected 70 patients with adverse reactions of central nervous system during the use of fluoroquinolones as the research object. We reviewed and analyzed the basic data, main manifestations and outcomes of adverse reactions, and summarized the influencing factors. The results showed that dizziness, irritability and insomnia were the main symptoms in 42 patients with mild adverse reactions. In 28 patients with moderate to severe adverse reactions, neuropsychiatric symptoms such as restlessness, depression, nervous excitation, phonism and hallucination were found. 54 patients were able to recover after stopping the medication. The remaining 16 patients were treated with drugs, and the effective rate was 87.5%. By analyzing the related factors, it can be seen that elderly patients over 60 years old, intravenous administration, combination of drugs and past history of neurological diseases are the main factors leading to adverse reactions of the central nervous system. In this survey, there were 7 kinds of adverse drug reactions, of which 31 cases (44.28%) were caused by levofloxacin. Therefore, fluoroquinolones have adverse effects on the central nervous system in the course of treatment, and the occurrence of adverse reactions is related to patients’ age, route of administration, drug combination and past history of illness. It is important to grasp the above factors and make rational use of drugs. [ABSTRACT FROM AUTHOR]

El Niño has two different flavors, eastern Pacific (EP) and central Pacific (CP) El Niños, with different global teleconnections. However, their different impacts on the interannual carbon cycle variability remain unclear. Here we compared the behaviors of interannual atmospheric CO2 variability and analyzed their terrestrial mechanisms duringthese two types of El Niños, based on the Mauna Loa (MLO) CO2 growth rate (CGR) and the Dynamic Global Vegetation Model's (DGVM) historical simulations. The composite analysis showed that evolution of the MLO CGR anomaly during EP and CP El Niños had three clear differences: (1) negative or neutral precursors in the boreal spring during anEl Niño developing year (denoted as "yr0"), (2) strong or weak amplitudes, and (3) durations of the peak from December (yr0) to April during an El Niño decaying year (denoted as "yr1") compared to October (yr0) to January (yr1) for a CP El Niño, respectively. The global land-atmosphere carbon flux (FTA) simulated by multi-models was able to capture the essentials of these characteristics. We further found that the gross primary productivity (GPP) over the tropics and the extratropical Southern Hemisphere (TropCSH) generally dominated the global FTA variations during both El Niño types. Regional analysis showed that during EP El Niño events significant anomalous carbon uptake caused by increased precipitation and colder temperatures, corresponding to the negative precursor, occurred between 30°S and 20°N from January (yr0) to June (yr0). The strongest anomalous carbon releases, largely due to the reduced GPP induced by low precipitation and warm temperatures, occurred between the equator and 20°N from February (yr1) to August (yr1). In contrast, during CP El Niño events, clear carbon releases existed between 10°N and 20°S from September (yr0) to September (yr1), resulting from the widespread dry and warm climate conditions. Different spatial patterns of land temperatures and precipitation in different seasons associated with EP and CP El Niños accounted for the evolutionary characteristics of GPP, terrestrial ecosystem respiration (TER), and the resultant FTA. Understanding these different behaviors of interannual atmospheric CO2 variability, along with their terrestrial mechanisms during EP and CP El Niños, is important because the CP El Niño occurrence rate might increase under global warming. [ABSTRACT FROM AUTHOR]

Large interannual atmospheric CO2 variability is dominated by the response of the terrestrial biosphere to El Niño-Southern Oscillation (ENSO). However, the behavior of terrestrial ecosystems differs during different El Niños in terms of patterns and biological processes. Here, we comprehensively compare two extreme El Niños (2015/16 and 1997/98) in the context of a multi-event "composite" El Niño. We find large differences in the terrestrial carbon cycle responses, even though the two events were of similar magnitude. More specifically, we find that the global-scale land-atmosphere carbon flux (FTA) anomaly during the 1997/98 El Niño was 1.64 PgCyr-1, but half that quantity during the 2015/16 El Niño (at 0.73 PgCyr-1). Moreover, FTA showed no obvious lagged response during the 2015/16 El Niño, in contrast to that during 1997/98. Separating the global flux by geographical regions, we find that the fluxes in the tropics and extratropical Northern Hemisphere were 1.70 and -0.05 PgCyr-1 during 1997/98, respectively. During 2015/16, they were 1.12 and -0.52 PgCyr-1, respectively. Analysis of the mechanism shows that, in the tropics, the widespread drier and warmer conditions caused a decrease in gross primary productivity (GPP; -0.73 PgCyr-1) and an increase in terrestrial ecosystem respiration (TER; 0.62 PgCyr-1) during the 1997/98 El Niño. In contrast, anomalously wet conditions occurred in the Sahel and East Africa during 2015/16, which caused an increase in GPP, compensating for its reduction in other tropical regions. As a result, the total 2015/16 tropical GPP and TER anomalies were -0.03 and 0.95 PgCyr-1. GPP dominance during 1997/98 and TER dominance during 2015/16 accounted for the phase difference in their FTA. In the extratropical Northern Hemisphere, the large difference occurred because temperatures over Eurasia were warmer during the 2015/16, as compared with the cooling seen during the 1997/98 and the composite El Niño. These warmer conditions enhanced GPP and TER over Eurasia during the 2015/16 El Niño, while these fluxes were suppressed during 1997/98. The total extratropical Northern Hemisphere GPP and TER anomalies were 0.63 and 0.55 PgCyr-1 during 1997/98, and 1.90 and 1.45 PgCyr-1 during 2015/16, respectively. Additionally, wildfires played a less important role during the 2015/16 than during the 1997/98 El Niño. [ABSTRACT FROM AUTHOR]

Single-phased white light-emitting YNbO: Bi, Eu phosphors were synthesized by conventional solid-state reaction. YNbO: Bi phosphor exhibits a broad excitation band ranging from 220 to 360 nm and a blue light emission band peaking at 457 nm, originating from the P-S transition of Bi, whereas YNbO: Eu phosphor exhibits the typical red emission aroused from the D → F, D → F, D → F, D → F transitions of Eu. Under the excitation at 330 nm, the YNbO: Bi, Eu exhibits both the blue emission band of Bi and the red emission of Eu due to the energy transfer from Bi to Eu ions. By tuning the Bi/Eu ratio via the energy transfer, the emission hue of YNbO: Bi, Eu varied from blue (0.16, 0.18) to white (0.33, 0.24) and eventually to red (0.62, 0.33). The mechanism of energy transfer from a sensitizer Bi to an activator Eu in YNbO: Bi, Eu phosphors was demonstrated to be an exchange interaction. [ABSTRACT FROM AUTHOR]

This study aimed to explore the survival of AIDS patients treated with traditional Chinese medicine (TCM) in addition to combined antiretroviral therapy (cART) and of AIDS patients treated with cART. Data of patients taking cART between 30 October 2003 and 30 October 2004 in the National TCM HIV Treatment Trial Program area were retrospectively analyzed, with follow-up from 30 October 2004 to 30 October 2012. The log-rank test was used to compare survival between the two groups. A Cox proportional hazards model was used to determine hazard ratios to identify prognostic factors. The study included 521 patients in the TCM + cART group followed up for 3548 person-years and 375 patients in the cART group followed up for 2523 person-years. Mortality rates were 3.2/100 person-years and 4.2/100 person-years in the TCM + cART and cART groups, respectively. The difference in survival was significant. After adjusting for explanatory variables, the mortality rate of AIDS patients in the cART group was 1.7 times higher than in the TCM + cART group. Male sex, older age, little education, and lower CD4 cell count were risk factors for mortality. TCM intervention in addition to cART could increase survival of AIDS patients. [ABSTRACT FROM AUTHOR]

A retrospective cohort study was conducted to explore the effectiveness of Traditional Chinese Medicine (TCM) in treating people living with HIV (PLHIV) by comparing the survival of PLHIV treated with TCM and without TCM. To identify prognostic factors that affect the survival of PLHIV, patients who enrolled in the national TCM HIV treatment trial program (NTCMTP) in October 2004 and PLHIV in the same region who did not enroll in the NTCMTP were compared. Participants were followed up to October 2012. Survival time was estimated through the Kaplan-Meier method, and hazard ratios to identify prognostic factors were computed through Cox proportional hazard models. A total of 3,229 PLHIV (1,442 in the TCM therapy group and 1,787 in the non-TCM therapy group) were followed up for 21,876 person-years. In this time period, 751 (23.3%) died and 209 (6.5%) were lost to follow-up, for an overall mortality rate of 3.43/100 person-years. In the TCM therapy group, 287 (19.0%) died and 139 (9.7%) were lost to follow-up, and in the non-TCM therapy group, 464 (26.0%) PLHIV died and 70 (3.9%) were lost to follow-up. The mortality rate in the TCM therapy group was 2.97/100 person-years, which was lower than the rate of 3.79/100 person-years in the non-TCM therapy group. The 8-year cumulative survival in the TCM therapy group was 78.5%, lower than the 74.0% survival in the non-TCM therapy group. After adjusting for other factors, risk factors of death included male gender, older age, less education, taking combined antiretroviral therapy (cART) at enrollment, not taking cART at follow-up, and lower CD4 + T cell counts. Our retrospective cohort study indicates that TCM increased the survival and lengthened the lifetime of PLHIV in Henan Province of China. However, the limitations of a retrospective cohort could have biased the study, so prospective studies should be carried out to confirm our primary results. [ABSTRACT FROM AUTHOR]

Highlights: [•] Sr12Al14O32Cl2:Eu2+ was synthesized by solid state reaction method. [•] Sr12Al14O32Cl2 crystallizes as a cubic structure with a space group of . [•] Sr12Al14O32Cl2:Eu2+ could be efficiently excited by near UV lights. [•] Sr12Al14O32Cl2:Eu2+ gives bright green emission band under near UV excitation. [ABSTRACT FROM AUTHOR]

Three types of observations, aerosol optical depth from the Moderate Resolution Imaging Spectroradiometer, surface particulate matter with diameters less than 2.5 (PM2.5) and 10 μm (PM10), and aerosol extinction coefficient (AEXT) profiles from ground‐based lidars, were separately and simultaneously assimilated using the Weather Research and Forecasting Model with the Chemistry/Data Assimilation Research Testbed (WRF‐Chem/DART). Two cases in June and November 2018 were selected over middle and eastern China. Experiments assimilating single‐type and multiple observations were evaluated by cross validating their analysis and forecast against the three observation types. Compared to the experiment without data assimilation (DA), DA of single‐type observations is always closer to the type of observations assimilated. However, DA of aerosol optical depth or AEXT sometimes significantly degraded the error performance for PM2.5. This problem is caused by the inconsistency of bias tendencies when modeling aerosol optical properties and surface aerosol mass. It is found that WRF‐Chem tends to predict dryer air within the boundary layer over eastern China, which may have played a role in the underestimation of AEXT even when PM2.5 was overestimated. After applying a simple bias correction (BC), the problem was alleviated. DA of multiple observations with BC gives the best overall error performance when validated against all types of observations and even performs better than any DA of single‐type observations experiments in reproducing AEXT profiles. The results illustrate that BC is important in DA of multiple observations and that the simultaneous DA of aerosol observations with different vertical information can work synergistically to improve aerosol forecasts. Key Points: Multiple aerosol data from satellite, surface site, and ground‐based lidar were assimilated, which improved model's overall performanceBias correction is crucial in data assimilation of multiple observations if bias tendencies are different in different observation typesA new bias correction method for ensemble Kalman filter was proposed and tested [ABSTRACT FROM AUTHOR]

Ca2Y3-xSb3O14: Bi3+x (x = 0.0225-0.75) phosphors are prepared by firing stoichiometric amounts of CaCO3, Y2O3, Sb2O3, and Bi2O3 (Al2O3 crucible, 1400 °C, 8 h). [ABSTRACT FROM AUTHOR]

Abstract: Visibility, Air Pollution Index (API) and meteorological parameters over Nanjing during 2004 are analyzed using multiple statistic methods to study the characterization of visibility and relevant affecting factors. The mean value of visibility during the study year is 8.8km, with 57.9% of daily average less than 10km. Annual average visibility exhibits a significant diurnal variation with minimum of 6.6km at 07:00 Local Time (LT) and maximum of 10.7km at 16:00 LT. Seasonal variations is weak: 9.2km in spring (March–May), 9.8km in summer (June–August), 8.2km in autumn (September–November), and 8.1km in winter (December–February), respectively. No significant weekend effect in visibility is found. Moreover, wavelet analysis reveals the significant periodic variations in visibility, with major periods of synoptic scale (2–8days), and quasi-two-week scale (8–17days). Using a high pass filtering technique to eliminate the seasonal trend, correlation analysis and principal component analysis (PCA) are carried out to investigate the relations between visibility and relevant factors and to understand the dominated processes/causes to the synoptic changes in visibility. Our results highlight the significant impact of synoptic weather on air pollution and visibility in Nanjing. [Copyright &y& Elsevier]

Abstract: Long afterglow phosphors (Ca1−x Eu x )2MgSi2O7 (0.002≤ x ≤0.02) were prepared by solid-state reactions under a weak reductive atmosphere. X-ray diffraction pattern, photoluminescence spectra, decay curve, afterglow spectra and thermoluminescence curves were investigated. The phosphors showed two emission peaks when they were excited by 343nm, due to two types of Eu2+ centers existing in the Ca2MgSi2O7 lattice. However, only one emission peak can be found in their afterglow spectra. Energy transfer between Eu2+ ions in inequivalent sites was found. A possible mechanism was presented and discussed. The afterglow decay time of Ca1.998MgSi2O7:Eu0.002 was nearly 12.5h which means it was a good long lasting phosphor. [Copyright &y& Elsevier]

Abstract: The Ho3+/Yb3+ co-doped NaGd(WO4)2 phosphors with different concentrations of Yb3+ were prepared by a facile hydrothermal route. X-ray diffraction and scanning electron microscopy were used to study the structure of the samples. The upconversion (UC) emission spectra of the samples were measured under 980nm excitation with different pumping power. Intense red luminescence at 625–675nm, weak blue luminescence at 458–492nm, green luminescence at 523–565nm and near infrared luminescence at 736–770nm emitted by Ho3+ were observed, and their emission intensities changed with the Yb3+ concentration. The transition mechanisms of the UC luminescence were also discussed. [Copyright &y& Elsevier]

Yangtze River Delta (YRD) region has experienced a remarkable urbanization during the past 30years, and regional climate change and air pollution are becoming more and more evident due to urbanization. Impacts of urban canopy on regional climate and air quality in dry- and wet-season are investigated in this paper, utilizing the Weather Research and Forecasting/Chemistry (WRF/Chem) model. Four regimes of urban canopy schemes with updated USGS land-use data in actual state of 2004 base on MODIS observations are examined: (1) SLAB scheme that does not consider urban canopy parameters (the control experiment in this paper); (2) a single-layer urban model with a fixed diurnal profile for anthropogenic heat (UCM); (3) multilayer urban canopy model (BEP-Building effect parameterization); (4) multilayer urban models with a building energy model including anthropogenic heat due to air conditioning (BEP+BEM). Results show that, compared with observations, the best 2-m temperature estimates with minimum bias are obtained with SLAB and BEP+BEM schemes, while the best 10-m wind speed predictions are obtained with BEP and BEP+BEM scheme. For PM10 and ozone predictions, BEP+BEM scheme predicted PM10 well during January, while the best estimate of PM10 is obtained with UCM scheme during July, BEP+BEM and SLAB schemes best estimated ozone concentrations for both the two months. Spatial differences of meteorological factors between canopy schemes and control scheme show that compared with SLAB scheme, BEP and BEP+BEM schemes cause an increase of temperature with differences of 0.5°C and 0.3°C, respectively, UCM scheme simulates lower temperature with decrease of 0.7°C during January. In July, all the canopy experiments calculates lower air temperature with reduction of 0.5°C–1.6°C. All the canopy experiments compute lower 10-m wind speed for both January and July. Decreases were 0.7m/s (0.8m/s) with UCM, 1.7m/s (2.6m/s) with BEP, and 1.8m/s (2.3m/s) with BEP+BEM schemes in January (July), respectively. For chemical field distributions, results show that, compared with SLAB scheme, UCM scheme calculates higher PM10 concentration in both January and July, with the differences of 22.3% (or 24.4μg/m3) in January, and 31.4% (or 17.4μg/m3) in July, respectively. As large as 32.7% (or 18.3 μg/m3) of PM10 increase is found over Hangzhou city during July. While 18.6% (or 22.1 μg/m3) and 16.7% (or 24.6 μg/m3) of PM10 decreases are fund in BEP and BEP+BEM schemes during January. Compared with control experiment during January, 6.5% (or 2.6ppb) to 10.4% (4.2ppb) increases of ozone are computed over mage-cities by canopy experiments. All the three canopy schemes predict lower ozone concentrations and as large as 30.2% (or 11.2ppb) decrease is obtained with UCM scheme, and 16.5% (6.2ppb) decrease with BEP scheme during July. The SLAB scheme is suitable for real-time weather forecast while multiple urban canopy scheme is necessary when quantify the urbanization impacts on regional climate. [ABSTRACT FROM AUTHOR]