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The directionality of thermal radiance of a homogeneous isothermal nonblack plane surface is totally decided by its directional emissivity, which depends on the complex dielectric constant and roughness of surface. It can be expressed by This paper proves that it is necessary to express emissivity by a matrix when a target becomes an inhomogeneous non-isothermal open complex with complicated inner geometric structure. The matrix describes the inner radiative interaction among components accurately and also expresses its thermal radiative directionality and structural characteristics completely. Advantages of matrix expression are as follows: first, the physical mechanics of effective emissivity of an open complex is described in a simple and perfect way; second, it becomes easy to understand the principle and method to retrieve components temperature from multiangle thermal remotely sensed data; and third, the differences of directionalities between an open complex and a homogeneous isothermal nonblack plane body are expressed by just using an effective emissivity matrix instead of an emissivity vector. Formula in classic physics is only the special case of matrix expression; therefore, the matrix is a universal unconditional expression to describe the directionality of thermal radiance.

This article is intentionally published to make erratum to the print version and the online version of Vol.60 (2017) NO. 2 ( https://link.springer.com/article/10.1007/s11430-015-0247-9 ). Citations of the following publications should be added to the list of Reference for TCCON data use: Wennberg P O, Roehl C M, Wunch D, Toon G C, Blavier J F, Washenfelder R A, Keppel-Aleks G, Allen N T, Ayers J. 2014. TCCON data from Park Falls, Wisconsin, USA, Release GGG2014R0. TCCON data archive, hosted by the Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA, http://dx.doi.org/10.14291/tccon.ggg2014.parkfalls01.R0/1149161 Wennberg P O, Wunch D, Roehl C M, Blavier J F, Toon G C, Allen N, Dowell P, Teske K, Martin C, Marti J. 2014. TCCON data from Lamont, Oklahoma, USA, Release GGG2014R0. TCCON data archive, hosted by the Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA, http://dx.doi.org/10.14291/tccon.ggg2014.lamont01.R0/1149159 We should have asked for approvals from relevant PIs before publication on the use of TCCON data and cited references by DOIs. We do apologize for the fault and will strictly follow the Data Use Policy in the future.

The horizontal and vertical distributions of aerosol optical properties over China in 2013–2015 were investigated using RAMS (Regional Atmospheric Modeling System)-CMAQ (Models-3 Community Multiscale Air Quality) simulations and CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) observations. To better understand the performance of the RAMS-CMAQ model over China, comparisons with the ground-based Sun photometers AERONET (Aerosol Robotic Network), MODIS (Moderate Resolution Imaging Spectroradiometers) data and the on-board Lidar CALIOP were used for comprehensive evaluations, which could characterize the abilities of the model to simulate the spatial and vertical distributions of the AOD (Aerosol Optical Depth) as well as the optical properties for four seasons. Several high value areas (e.g., the Sichuan Basin, Taklamakan Desert, North China Plain, and Yangtze River Delta) were found over China during the study period, with the maximum mean AOD (CALIOP: ~0.7; RAMS-CMAQ: >1) in the Sichuan district. Compared with AODs of AERONET, both the CALIOP and RAMS-CMAQ AODs were underestimated, but the RAMS-CMAQ data show a better correlation with AERONET (AERONET vs. RAMS-CMAQ R: 0.69, AERONET vs. CALIOP R: 0.5). The correlation coefficients between RAMS-CMAQ and CALIOP are approximately 0.6 for all four seasons. The AEC (Aerosol Extinction Coefficient) vertical profiles over major cities and their cross sections exhibit two typical features: (1) most of the AEC peaks occurred in the lowest ~0.5 km, decreasing with increasing altitude; and (2) the RAMS-CMAQ AEC underestimated the region with high AODs in the northwest of China and overestimated the region with high AODs in the east–central plain and the central basin regions. The major difference in the AEC values of RAMS-CMAQ and CALIOP is mainly caused by the level of relative humidity and the hygroscopic growth effects of water-soluble aerosols, especially, in the Sichuan district. In general, both the column and vertical RAMS-CMAQ aerosol optical properties could be supplemented efficiently when satellite observations are not available or invalid over China in the applications of climate change and air pollution.

The rapid changes of aerosol sources in eastern China during recent decades could bring considerable uncertainties for satellite retrieval algorithms that assume little spatiotemporal variation in aerosol single scattering properties (such as single scattering albedo (SSA) and the size distribution for fine-mode and coarse mode aerosols) in East Asia. Here, using ground-based observations in six AERONET sites, we characterize typical aerosol optical properties (including their spatiotemporal variation) in eastern China, and evaluate their impacts on Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 6 aerosol retrieval bias. Both the SSA and fine-mode particle sizes increase from northern to southern China in winter, reflecting the effect of relative humidity on particle size. The SSA is ~0.95 in summer regardless of the AEROENT stations in eastern China, but decreases to 0.85 in polluted winter in northern China. The dominance of larger and highly scattering fine-mode particles in summer also leads to the weakest phase function in the backscattering direction. By focusing on the analysis of high aerosol optical depth (AOD) (>0.4) conditions, we find that the overestimation of the AOD in Dark Target (DT) retrieval is prevalent throughout the whole year, with the bias decreasing from northern China, characterized by a mixture of fine and coarse (dust) particles, to southern China, which is dominated by fine particles. In contrast, Deep Blue (DB) retrieval tends to overestimate the AOD only in fall and winter, and underestimates it in spring and summer. While the retrievals from both the DT and DB algorithms show a reasonable estimation of the fine-mode fraction of AOD, the retrieval bias cannot be attributed to the bias in the prescribed SSA alone, and is more due to the bias in the prescribed scattering phase function (or aerosol size distribution) in both algorithms. In addition, a large yearly change in aerosol single scattering properties leads to correspondingly obvious variations in the time series of MODIS AOD bias. Our results reveal that the aerosol single scattering properties in the MODIS algorithm are insufficient to describe a large variation of aerosol properties in eastern China (especially change of particle size), and can be further improved by using newer AERONET data.

Mapping the components, size, and absorbing/scattering properties of particle pollution is of great interest in the environmental and public health fields. Although the Multi-angle Imaging SpectroRadiometer (MISR) can detect a greater number of aerosol microphysical properties than most other spaceborne sensors, the Angstrom exponent (AE) and single-scattering albedo (SSA) products are not widely utilized or as robust as the aerosol optical depth (AOD) product. This study focused on validating MISR AE and SSA data using AErosol RObotic NETwork (AERONET) data for China from 2004 to 2014. The national mean value of the MISR data (1.08) was 0.095 lower than that of the AERONET data. However, the MISR SSA average (0.99) was significantly higher than that of AERONET (0.89). In this study, we developed a method to improve the AE and SSA by narrowing the selection of MISR mixtures via the introduction of the following group thresholds obtained from an 11-year AERONET dataset: minimum and maximum values (for the method of MISR_Imp_All) and the top 10% and bottom 10% of the averaged values (for MISR_Imp_10%). Overall, our improved AE values were closer to the AERONET AE values, and additional samples (MISR_Imp_All: 28.04% and 64.72%, MISR_Imp_10%: 34.11% and 73.13%) had absolute differences of less than 0.1 and 0.3 (defined by the expected error tests, e.g., EE_0.1) compared with the original MISR product (18.46% and 50.23%). For the SSA product, our method also improved the mean, EE_0.05, and EE_0.1 from 0.99, 16.13%, and 56.45% (MISR original product) to 0.96, 40.32%, and 70.97% (MISR_Imp_All), and 0.94, 54.84%, and 90.32% (MISR_Imp_10%), respectively.

In the past decades, continuous efforts have been made at a national level to reduce Nitrogen Dioxide (NO2) emissions in the atmosphere over China. However, public concern and related research mostly deal with tropospheric NO2 columns rather than ground-level NO2 concentrations, but actually ground-level NO2 concentrations are more closely related to anthropogenic emissions, and directly affect human health. This paper presents one method to derive the ground-level NO2 concentrations using the total column of NO2 observed from the Ozone Monitoring Instrument (OMI) and the simulations from the Community Multi-scale Air Quality (CMAQ) model in China. One year’s worth of data from 2014 was processed and the results compared with ground-based NO2 measurements from a network of China’s National Environmental Monitoring Centre (CNEMC). The standard deviation between ground-level NO2 concentrations over China, the CMAQ simulated measurements and in-situ measurements by CNEMC for January was 21.79 μg/m3, which was improved to a standard deviation of 18.90 μg/m3 between our method and CNEMC data. Correlation coefficients between the CMAQ simulation and in-situ measurements were 0.75 for January and July, and they were improved to 0.80 and 0.78, respectively. Our results revealed that the method presented in this paper can be used to better measure ground-level NO2 concentrations over China.

Sulfur dioxide (SO 2) has a significant impact on the urban environment pollution and global climate. Compared with regional ground monitoring networks, satellite remote sensing technology provides an unprecedented advantage for continuous, large spatial and short-revisit monitoring for atmospheric SO 2 . Approaches for retrieval of SO 2 from ultraviolet satellite observations have been developed and applied to detection of volcanic SO 2 and regional emissions. However, these retrieval algorithms do not consider the temperature variation effect on SO 2 retrievals, and simply use the absorption coefficient at a constant temperature as inputs for SO 2 retrievals. In this study, hyperspectral OMI measurements were used to analyze the temperature effects on the retrieval of SO 2 columns. Results of DOAS algorithm showed that with increasing SO2 concentration, the retrieval errors caused by temperature effects accumulated, and the differences in SO2 columns increased to a maximum of ~25 DU (SO 2 column of 293K: ~65 DU). Therefore, atmospheric temperature is an important factor which has significant influence to high precise atmospheric SO 2 retrievals.

GSK1322322 (N-((R)-2-(cyclopentylmethyl)-3-(2-(5-fluoro-6-((S)-hexahydropyrazino[2,1-c][1,4]oxazin-8(1H)-yl)-2-methylpyrimidin-4-yl)hydrazinyl)-3-oxopropyl)-N-hydroxy-formamide) is an antibiotic in development by GlaxoSmithKline. In this study, we investigated the metabolism and disposition of [(14)C]GSK1322322 in healthy humans and demonstrated the utility of the Entero-Test in a human radiolabel study. We successfully collected bile from five men using this easy-to-use device after single i.v. (1000 mg) or oral administration (1200 mg in a solution) of [(14)C]GSK1322322. GSK1322322 had low plasma clearance (23.6 liters/hour) with a terminal elimination half-life of ∼4 hours after i.v. administration. After oral administration, GSK1322322 was readily and almost completely absorbed (time of maximal concentration of 0.5 hour; bioavailability 97%). GSK1322322 predominated in the systemic circulation (>64% of total plasma radioactivity). An O-glucuronide of GSK1322322 (M9) circulated at levels between 10% and 15% of plasma radioactivity and was pharmacologically inactive. Humans eliminated the radioactive dose in urine and feces at equal proportions after both i.v. and oral doses (∼45%-48% each). Urine contained mostly unchanged GSK1322322, accounting for 30% of the dose. Bile contained mostly M9, indicating that glucuronidation was likely a major pathway in humans (up to 30% of total dose). In contrast, M9 was found in low amounts in feces, indicating its instability in the gastrointestinal tract. Therefore, without the Entero-Test bile data, the contribution of glucuronidation would have been notably underestimated. An unusual N-dehydroxylated metabolite (a secondary amide) of GSK1322322 was observed primarily in the feces and was most likely formed by gut microbes.

The spatial and temporal characteristics of fine particulate matter (PM2.5, particulate matter

After carefully studying the results of retrieval of land surface temperature(LST) by multi-channel thermal infrared remote sensing data, the authors of this paper point out that its accuracy and significance for applications are seriously damaged by the high correlation coefficient among multi-channel information and its disablement of direct retrieval of component temperature. Based on the model of directional radiation of non-isothermal mixed pixel, the authors point out that multi-angle thermal infrared remote sensing can offer the possibility to directly retrieve component temperature, but it is also a multi-parameter synchronous inverse problem. The results of digital simulation and field experiments show that the genetic inverse algorithm (GIA) is an effective method to fulfill multi-parameter synchronous retrieval. So it is possible to realize retrieval of component temperature with error less than 1K by multi-angle thermal infrared remote sensing data and GIA.

The style of crops planting is frequently in row-structure, the row-structure style may result in big difference among the sunlit, shaded soil surface and foliage temperatures and cause pixel component to vary in azimuth orientation, these further lead to the change of radiant directionlity of row crops in the zenith and azimuth orientations. Since the row crops are often tackled as isotropic in the azimuth orientation based on continuous vegetation assumption, big errors will be brought about. In order to eliminate the errors, it is necessary to study the law of radiant directionality of the row crops. In this paper, Monte Carlo method has been employed to simulate the angular effects on radiation caused by row architecture parameters. The simulated results show that the parameters, for example, row height, row width, row interval between the neighbor rows and the leaf area index have significant influences on the radiant directionality, but the azimuth orientation ranks the first among the parameters.

In 1991, J. Labed, et al. offered a formula of passive measurement of directional emissivity of object in laboratory. It is based on two preconditions, blackbody background radiation and the temperature of target (T t) different to background temperature (T b) and the bigger the differenceΔT(ΔT=Tt−Tb) is, the higher the accuracy of measurement will be. In fact, only approximate black-body exists, asT t≠Tb, it is more difficult to satisfy the precondition of “blackbody background radiation”. Authors of this paper re-deduce this formula under the condition of non-blackbody background and a new concept of effective emissivity. Our results had been proven by Monte Carlo’s simulation and experiments. We re-explain the experimental results offered by J. Labed et al. and whyɛ r, 3.7(θ) reduces more rapidly thanɛ r, 10.6(θ) andɛ r, 12(θ) as θ increases.

Based on two preconditions, the local thermal equilibrium is satisfied and emissivities do not change with temperature, the concept of component effective emissivity of nonisothermal mixed pixel has been put forward and then the radiant directionality model of nonisothermal mixed pixel constructed from it. Our study shows that the component effective emissivity is associated with geometric structure, optical properties of target, and viewing angle, but does not depend on the component temepratures. The component temperatures can only change the ratio of component radiance to the total radiance of the mixed-pixel. The total effective emissivity of this pixel is the complement of its directional-hemisphere reflectance. After the simulation of component effective emissivity of the discrete cones and continuous vegetation canopy (winter wheat) by the Monte Carlo method, our model of radiant directionality of nonisothermal mixed pixel have been proved by lab and field measurements.

Summary In plant cells, the interconversion of formyl- and methylene-tetrahydrofolates is catalyzed by a bifunctional protein possessing methenyltetrallydrofolate cydohydrolase (EC 3.5.4.9) and methylenetetrahydrofolate dehydrogenase (EC 1.5.1.5) activities. The present work reports the isolation and sequencing of a cDNA that encodes this protein. Polydonal antibodies, raised against purified pea cytosolic dehydrogenase:cyclohydrolase, were used to screen a λgt 11 cDNA expression library, constructed from leaf extracts of this species. The screen identified a phage containing a cDNA insert with an open reading frame encoding a 294 amino acid protein (Mr 31,344). The deduced primary structure of this protein contained most of the conserved regions found in other dehydrogenase:cyclohydrolase proteins including the corresponding domains of the trifunctional C1-THF synthases of mammalian and yeast origins.

The informational correlation among seven thermal infrared channels of MODIS is simulated. Results show that they have high correlation coefficient, which becomes one of the main obstacles to raise accuracy of LST retrieved by the remote sensing method. By means of principal component analysis we have proven 14 independent equations for retrieval of LST at most having five independent informative components, if seven bands are chosen for retrieval of LST, only three independent informative components exist. Therefore the property of retrieval of LST belongs to the underdetermined inverse problem. We cannot expect to get a stable and high accurate LST retrieved by various currently used remote sensing methods based on determined equations. From now on it is a main research topic to retrieve LST by underdetermined equations.

Folate-dependent pathways of one-carbon metabolism are essential for the synthesis of purines, formylmethionyl-tRNA, thymidylate, serine and methionine. These syntheses use a cellular source of one-carbon substituted, tetrahydrofolate polyglutamate derivatives which are the preferred substrates of most folate-dependent enzymes. In the last decade, there have been major advances in the folate biochemistry of animal, bacterial, fungal and plant systems. These have included the refinement of methods for folate isolation and characterization, basic work on key enzymes of folate biosynthesis and the detailed characterization of proteins that catalyze the generation and utilization of one-carbon substituted folates.

Several drug–drug interaction (DDI) prediction models were evaluated for their ability to identify drugs with cytochrome P450 (CYP)3A induction liability based on in vitro mRNA data. The drug interaction magnitudes of CYP3A substrates from 28 clinical trials were predicted using (i) correlation approaches (ratio of the in vivo peak plasma concentration (Cmax) to in vitro half-maximal effective concentration (EC50); and relative induction score), (ii) a basic static model (calculated R3 value), (iii) a mechanistic static model (net effect), and (iv) mechanistic dynamic (physiologically based pharmacokinetic) modeling. All models performed with high fidelity and predicted few false negatives or false positives. The correlation approaches and basic static model resulted in no false negatives when total Cmax was incorporated; these models may be sufficient to conservatively identify clinical CYP3A induction liability. Mechanistic models that include CYP inactivation in addition to induction resulted in DDI predictions with less accuracy, likely due to an overprediction of the inactivation effect. Clinical Pharmacology & Therapeutics (2014); 95 2, 216–227. doi:10.1038/clpt.2013.170

A cytosolic protein, that exhibits NADP-dependent 5,10-methylenetetrahydrofolate dehydrogenase (EC 1.5.1.5) and 5,10-methenyltetrahydrofolate cyclohydrolase (EC 3.5.4.9) activities but lacks 10-formyltetrahydrofolate synthetase (EC 6.3.4.3) activity, was isolated from extracts of pea ( Pisum sativum L.) cotyledons and leaves. Dehydrogenase: cyclohydrolase activities co-purified when protein was fractionated by (NH 4 ) 2 SO 4 precipitation, followed by chromatography on Sephacryl S-300, Matrex Green A and heparin agarose. The resulting protein ( M r 38 500) was apparently homogeneous after SDS-polyacrylamide gel electrophoresis and silver staining. Purified enzyme preparations lacked methylenetetrahydrofolate dehydrogenase activity when NAD replaced NADP in the reaction system. Attempts to sequence this protein suggested that it may be blocked at the N -terminus. Tryptic digestion of the purified protein resulted in coordinate losses of dehydrogenase and cyclohydrolase activity. The NADP provided significant protection of both enzyme activities during short-term treatments with trypsin but additions of 5,10-methylenetetrahydrofolate appeared to accentuate the proteolytic loss of dehydrogenase activity. The apparent Michaelis constants for NADP (11 μM) and methylenetetrahydrofolate (21 μM) in the dehydrogenase reaction were not changed significantly when the folylpentaglutamate substrate was provided (8 and 25 μM, respectively). The dehydrogenase and cyclohydrolase activities were competitively inhibited by dihydrofolates. The K i values of the dehydrogenase reaction indicated that the pentaglutamate derivative was a more potent inhibitor than dihydrofolate monoglutamate. The ELISA and Western blot analyses, using rabbit polyclonal antibodies raised against the purified enzyme, revealed cross-reactivity with proteins of similar molecular size in leaf extracts of wheat, barley, corn, bean and pea. Chromatography of these leaf extracts on Matrex Green A, in the presence of protease inhibitors, showed that 10-formyltetrahydrofolate synthetase was readily separated from protein with dehydrogenase and cyclohydrolase activity.

Widespread haze layers usually cover China like low clouds, exerting marked influence on air quality and regional climate. With recent Collection 6 MODIS Deep Blue aerosol data in 2000–2015, we analyzed the trends of regional haze pollution and the corresponding influence of atmospheric circulation in China. Satellite observations show that regional haze pollution is mainly concentrated in northern and central China. The annual frequency of regional haze in northern China nearly doubles between 2000 and 2006, increasing from 30–50 to 80–90 days. Though there is a marked decrease in annual frequency during 2007–2009 due to both reduction of anthropogenic emissions and changes of meteorological conditions, regional pollution increases slowly but steadily after 2009, and maintains at a high level of 70–90 days except for the sudden decrease in 2015. Generally, there is a large increase in the number of regional-scale haze events during the last decade. Seasonal frequency of regional haze exhibits distinct spatial and temporal variations. The increasing winter haze events reach a peak in 2014, but decrease strongly in 2015 due partly to synoptic conditions that are favorable for dispersion. Trends of summer regional haze pollution are more sensitive to changes of atmospheric circulation. Our results indicate that the frequency of regional haze events is associated not only with the strength of atmospheric circulation, but also with its direction and position, as well as variations in anthropogenic emissions.

There are four CCD cameras with spatial resolution of 30 m in Environment Satellite 1 (HJ-1), the new satellite developed by China. In the paper, deep blue algorithm for CCD/HJ-1 is applied to Ning-bo. Based on the database of surface reflectance from MODerate-resolution Imaging Spectroradiometer (MODIS) spectral reflectance product and look-up table (LUT), aerosol optical depth (AOD) over cloud-free land pixel is retrieved from apparent reflectance in the first band of CCD/HJ-1. AODs over Ning-bo area are retrieved from January to September in 2011, and the results are validated by ground-based measurements of CE318 in the center of Ning-bo city. The validation shows that the retrieved AODs are larger than that of ground-based measurements, but correlation coefficient (R) is greater than 0.7. Further improvements of overestimated AODs is the focus of our future research.

[1] Haze clouds often form over the North China Plain (NCP) of eastern China, where large amounts of aerosol particles and their precursors are emitted. To obtain general insights into regional pollution, a large-scale, long-term study was conducted using A-Train satellite observations, ground measurements, and meteorological data. Contrary to previous analyses, most of the haze clouds appeared to form abruptly (within 2–3 h). Case studies show that natural sources contribute significantly to the formation of regional haze. Dust plumes can mix with local pollutants, causing smog clouds to form abruptly, while moist airflows can cause widespread haze-fog pollution. The combined observations revealed highly inhomogeneous haze clouds, in terms of both vertical and horizontal distribution, leading to clear discrepancies between site measurements near the surface and satellite observations at the top of the atmosphere. Surprisingly, prevailing dust plumes, which are closely connected with the haze clouds, were observed in winter. Airborne dust and water vapor transported from outside the region are the main drivers of regional haze over the NCP. Accumulation of local pollutants also leads to common occurrences of urban smog; however, the occurrence of most haze clouds shows no obvious correlation with local pollution. Local- and regional-scale haze pollution are common over the NCP, but they have differing formation mechanisms, and contrasting chemical and physical properties. The present findings improve our understanding of heavy pollution over eastern China and its links to climate.

Understanding the spatial and temporal variation of pollutant concentrations over power plant is important for optimizing emission control strategies. Remote sensing technology can help to expand the sparse ground monitoring networks into regions currently not covered. This paper use the monthly mean sulfur dioxide (SO 2 ) and nitrogen dioxide (NO 2 ) from Ozone Monitoring Instrument (OMI) on board NASA's Aura satellite to assess the air quality in several coal-fired power plants over the North China Plain. Our analysis indicates: 1) The inter-annual variation (2007∼2009) of SO 2 and NO 2 showed the implement of flue-gas desulfurization (FGD) devices in power plants was effectiveness; 2) Due to lack of NO 2 national standard and the increasing NO 2 emissions from automobiles, the NO 2 pollutions have a trend of increment in North China Plain in the past decade; 3) By comparing the monthly mean SO 2 and NO 2 of several big coal-fired power plants over the mountain and plain area, we found that the power output directly affects pollutant concentrations.

Spaceborne measurements by Atmospheric Infrared Sounder (AIRS) on the EOS/Aqua satellite provide a global view of methane (CH 4 ) distribution in the mid-upper troposphere (MUT-CH 4 ) since September, 2002. In the AIRS retrieval algorithm, a modified Optimal Estimation Model (OEM) is utilized based on Singular Value Decomposition (SVD) technique, which minimizes the dependence of the solution to the first-guess field and the first-guess error characteristics and can get an accurate CH 4 retrieval at the maximum sensitive layer in the mid-upper troposphere. Nevertheless, in the less sensitive layer, the CH 4 retrieval is close to the first-guess. Therefore, a better first-guess can improve the accuracy and efficiency of CH 4 vertical profile retrieval. In this paper, a stable inversion model based on Empirical Orthogonal Functions (EOF) of computational efficiency and acceptable accuracy was developed to solve the above problems. Based on RTTOV 10.2 (a high precision atmospheric radiative transfer model for AIRS), an empirical regression model based on orthogonal function was formulized to retrieve CH 4 vertical profile from spacebonre hyperspectral infrared observations. Validation of AIRS CH 4 total column amount retrieved from EOF versus FTIR measurements shows that its Person correlative coefficient is bigger than 0.85. The CH 4 volume mixing ratio (VMR) near surface retrieved from EOF versus Mt. Waliguan, China (WLG, 36.2879°N 100.8964°E, 3810 m) shows that the RMS error is less than 1.5%. The regression model based on EOF can retrieve CH 4 profile from spaceborne hyperspectral infrared observations in a rapid and stable way.

Alpine ecosystems are highly sensitive to global climate changes. The Tibetan Plateau is one of the areas that are most sensitive to global climate change. Increases in temperature and changes in precipitation can impact the plateau's ecosystem productivity. Net primary productivity (NPP) is one of the most important factors in the carbon cycle of terrestrial ecosystems. In this paper, a light-use-efficiency model was used to estimate the net primary productivity in the Tibetan Plateau. The model is based on a 1-km1-km-resolution map of vegetation type, multi-temporal 500-m-resolution MODIS data and daily meteorological data. The spatial distribution pattern and dynamic change of the annual NPP from 2001 to 2008 are analyzed. Then, we analyzed the response of the NPP to temperature and precipitation changes. The results show that the mean annual NPP of alpine ecosystems in the Tibetan Plateau is equal to 0.472 Pg C and that the NPP exhibits significant seasonal and interannual variation due to the combined effects of temperature and precipitation changes. Finally, to analyze the effect of temperature and precipitation on the inter-annual change of the NPP, the correlation coefficient between temperature, precipitation and the NPP was computed. It was found that the relations among air temperature, precipitation and the NPP in the Tibetan Plateau region are different. The annual average temperature increase had a significantly positive effect on the vegetation NPP (R2=0.83). In contrast, the annual precipitation changes had a weakly negative effect on the vegetation NPP (R2=0.373). 2012 Elsevier B.V.

In this study, the land surface temperature (LST) from Moderate Resolution Imaging Spectroradiometer (MODIS) sensor which was chosen as one scalar temperature directly modifying light use efficiency (LUE), together with the 8-day composited MODIS data and the site measurements of photosynthetically active radiation (PAR) of a subtropical evergreen coniferous forest ecosystem in southern China during 2005–2006 are used to estimate the seasonal variations of gross primary production (GPP) with the Production Efficiency Model (PEM). To investigate the possibility of LST instead of atmospheric temperature (T a ) in the PEM model to estimate the GPP values, the LST predicted GPP (GPP LST ) and T a predicted GPP (GPP air ) are used to compare the GPP values observed from eddy covariance measurements (GPP obs ). It was found that the coefficient of determination of the fitted exponential equations between the GPP obs and the T a (r2 = 0.89) was slightly higher than that between the GPP obs and the LST(r2 = 0.80), and both variables could explain above 80 % variations of the GPP obs in this area. Both the GPP LST and GPP air agreed well with the observed GPP obs .There was a very strong linear relation between GPP LST and GPP air (r2 = 0.99), and they both were highly correlated with the GPP obs (r2 = 0.91 and 0.91, respectively). The annual total GPP LST and GPP air values (1630.6 and 1598.6 g C m−2 for 2005; 1740.2 and 1660.8 g C m−2 for 2006, respectively) were slightly lower than the GPP obs (1646.8 and 1867.4 g C m−2, respectively), and the error of the predicted GPP from LST (0.98% and 6.8% for 2005 and 2006, respectively) was smaller than the predicted GPP from T a (2.9% and 11.1% for 2005 and 2006, respectively) for the whole year data. These results demonstrate that the LST can be potentially used to estimate GPP instead of T a .

Dense Dark Vegetation algorithm (DDV) is effectively used in retrieval of aerosol optical depth (AOD) from satellite images over land. However, the algorithm is only suitable for low albedo areas such as water and dense vegetation areas. The purpose of this paper is mainly to retrieve aerosol optical depth over none DDV pixels by using the kriging interpolation method, we first retrieve the aerosol optical depth from EOS-MODIS data (a resolution of 1km∗1km) by the DDV algorithm, but there are many missing values distributed on the image. Then we interpolate the AOD image and get values of none DDV pixels with the kriging interpolation method. Our results show that the kriging interpolation results are consistent better with the surface observations than traditional interpolation methods and produce a better visual effect than the original image.

β-Naphthoflavone (BNF) is a synthetic flavone that selectively and potently induces CYP1A enzymes via aryl hydrocarbon receptor activation. Mechanism-based mathematical models of CYP1A enzyme induction were developed to predict the time course of enzyme induction and quantitatively evaluate the interrelationship between BNF plasma concentrations, hepatic CYP1A1 and CYP1A2 mRNA levels, and CYP1A enzyme activity in rats in vivo. Male Sprague-Dawley rats received a continuous intravenous infusion of vehicle or 1.5 or 6 mg · kg(-1) · h(-1) BNF for 6 h, with blood and liver sampling. Plasma BNF concentrations were determined by liquid chromatography-tandem mass spectrometry. Hepatic mRNA levels of CYP1A1 and CYP1A2 were determined by TaqMan. Ethoxyresorufin O-deethylation was used to measure the increase in CYP1A enzyme activity as a result of induction. The induction of hepatic CYP1A1/CYP1A2 mRNA and CYP1A activity occurred within 2 h after BNF administration. This caused a rapid increase in metabolic clearance of BNF, resulting in plasma concentrations declining during the infusion. Overall, the enzyme induction models developed in this study adequately captured the time course of BNF pharmacokinetics, CYP1A1/CYP1A2 mRNA levels, and increases in CYP1A enzyme activity data for both dose groups simultaneously. The model-predicted degradation half-life of CYP1A enzyme activity is comparable with previously reported values. The present results also confirm a previous in vitro finding that CYP1A1 is the predominant contributor to CYP1A induction. These physiologically based models provide a basis for predicting drug-induced toxicity in humans from in vitro and preclinical data and can be a valuable tool in drug development.

Folate-dependent pathways of one-carbon metabolism are essential for the synthesis of purines, formylmethionyl-tRNA, thymidylate, serine and methionine. These syntheses use a cellular source of one-carbon substituted, tetrahydrofolate polyglutamate derivatives which are the preferred substrates of most folate-dependent enzymes. In the last decade, there have been major advances in the folate biochemistry of animal, bacterial, fungal and plant systems. These have included the refinement of methods for folate isolation and characterization, basic work on key enzymes of folate biosynthesis and the detailed characterization of proteins that catalyze the generation and utilization of one-carbon substituted folates.

AOTs(Aerosol optical thicknesses) and aerosol size distribution functions in Pearl River Delta area are derived from PARASOL (Polarization and Anisotropy of Reflectances for Atmospheric Science coupled with Observations from a LIDAR)multi-directional, multi-spectral polarized signals. Based on analyzing the products of AERONET(Aerosol Robotic Network), aerosol size distribution function and complex refractive index over Pearl River Delta area are received. After that, the particular aerosol model is abstracted. The land surface polarized contribution is calculated using semi empirical model as a function of surface type and NDVI, and the pure atmospheric contribution is computed with a radiative transfer code. Compared with the products of the ground-based AERONET, the derived AOTs are underestimated against AERONET measurement. The retrieved size distribution for the radii bigger than 0.2 micron is also underestimated due to that polarization is insensitive to coarse model aerosol.

In this paper, we explored the changes of air quality over Jing-Jin-Tang (Beijing-Tianjin-Tangshan) district during the period from 2002 to 2009. Based on Moderate Resolution Imaging Spectroradiometer (MODIS) data, Dense Dark Vegetation (DDV) algorithm is employed to retrieve the aerosol optical thickness (AOT) with 1-km resolution. Comparison of the satellite inferred AOT and the values from ground-based Aerosol Robotic Network (AERONET) sun/sky radiometer measurements indicates a good agreement (R2=0.786) in Beijing site. We compared the spatial, monthly and annual variation over Jing-Jin-Tang district and analyzed the main factors of these changes. Our study indicates that there is a decreasing trend in the annual variation of AOT since 2004. The averages of AOT were commonly higher in spring and summer than those in autumn and winter, and the retrieved AOT over cities and southern areas is obviously larger than that over rural and northern areas respectively.

The Ring effect refers to the filling in of Fraunhofer lines, which is known as solar absorption lines, caused almost entirely by Rotational Raman scattering. The Rotational Raman scattering by N 2 and O 2 in the atmosphere is the main factor that leads to Ring effect. Basically, the Ring effect is considered as a pseudo-absorption process in retrieval of trace gas constituents in atmosphere. The solar spectrum measured by OMI/AURA is convolved with rotational Raman cross sections of N 2 and O 2 , divided by the original solar spectrum, with a cubic polynomial subtracted off, to create a differential Ring spectrum. This method has been suggested in order to obtain an effective differential Ring cross-section for the DOAS fitting process. The differential Ring spectrum could be used to improve the accuracy of the retrieval of the trace gases concentration. The results have been in basic agreement with the corresponding results calculated with RTM, and the R2 statistic is 0.9663.Next, the differential Ring spectrum calculated with rotational Raman cross sections of atmosphere in the fixed wavelength of 410nm and 488nm are derived. The results with the fixed wavelength have been also in basic agreement with the corresponding results calculated with RTM, and the R2 statistics are 0.9624 and 0.9639 respectively. At last but not the least, the computational complexity calculated at fixed wavelength of 410nm or of 488nm is 0.128% of that calculated with wavelengths from 410nm to 488nm.

A computationally efficient reflectance model for row planted canopies is developed in this paper through separating the contributions of incident direct and diffuse radiation scattered by row canopies. The row model allows calculating the reflectance spectrum in any given direction for the optical spectral region. The performance of the model is evaluated through comparisons with field measurements of winter wheat as well as with an established 3D computer simulation model. Especially the systematic comparisons with the computer simulation model demonstrate that the model can adequately simulate the characteristic distribution of directional reflectance factors of row canopies, which is shown in the polar map of reflectance as a high or low value stripe approximately parallel to the row orientation, besides the hotspot effect. Physical mechanisms causing the dynamics were proposed and supported by comparison studies. The features of reflectance distributions of row canopies, which are distinctively different from those of homogeneous canopy, imply that it is problematic to use one-dimensional radiation transfer model to interpret radiation data and estimate the structural or spectral parameters of row canopies from reflectance measurements. Finally, further improvements needed for the current model are briefly discussed.

Atmospheric aerosol plays a significant role in radiative budget, climate change, hydrological processes, and the global carbon, nitrogen and sulfur cycles. Aerosol optical thickness (AOT) is a key property used in the characterization of atmospheric aerosol. There is a relatively long history of the quantitative estimation of AOT from remotely sensed imagery; especially the dark object method has already made many progresses in the retrieval of AOT over the areas with low surface reflectance. Based on the analysis of the advantages and limits of dark object method, extended dark object method, V5.2 algorithm and four-branched decision method, we introduce a combined method to retrieve AOT over some areas around Beijing using moderate resolution imaging spectroradiometer (MODIS) data, the retrieval results are validated with AERONET data in Beijing and Xianghe sites.

In this paper, the retrieval of aerosol over land surfaces from CCD data of China Brazil Earth Resources Satellite (CBERS) 02B was studied. The method is dark dense vegetation (DDV) algorithm: 1) dense vegetation (dark pixel) was recognized by the NDVI threshold; 2) the look up table (LUT) of atmosphere was computed from the Satellite Signal in the Solar Spectrum (6S) model; 3) the aerosol was retrieved through interpolating the LUT by CCD data. The method was applied to Beijing area, and the retrieved aerosol was validated by ground-based measurements of CE318. The result shows that from CBERS02B data, the aerosol can be retrieved well.

Nitrogen dioxide (NO2) plays a key role in the chemistry of the atmosphere. Based on the space borne measurements, the Differential Optical Absorption Spectroscopy (DOAS) method determines the NO2 slant column density (SCD) along the light path through the atmosphere in a given spectral window between 405 and 465 nm. Based on radiative transfer model, a Look-Up-Table (LUT) of Air Mass Factor (AMF) is derived. The look-up parameters of the LUT are the solar zenith angles (SZA) and the detector viewing zenith angles (VZA), azimuth angles (AA), the surface albedo, the aerosol loading, the cloud parameters and the profiles of pressure and temperature. Conventionally, the MF values are derived using interpolation from LUT, which leads to bias. The accuracy can be improved by the application of Support Vector Machine (SVM). The AMF of the LUT is used to be samples of SVM. By training the samples and predicting, the appropriate AMF values are derived. For comparison, the interpolation AMF values are also calculated. The intercomparison result shows the accuracy of SVM method is comparable to that of interpolation approach.

On the eve of Beijing Olympic Games (BOG), frequent haze days had been extensively concerned by home and abroad. Ground-based and satellite remote sensing project was carried out to monitor haze distribution and intension by Chinese Academy of Sciences. Based on the assumption that surface reflectance vary slowly in a relative short period, the Haze Optical Thickness(HOT) retrieval model using MODIS data is established. Aerosol type is selected according to the ground experiment of haze particle composing in Central North China Plain. This model avoid that NASA Dense Dark Vegetation (DDV) algorithm couldn't determine the radio of surface reflectance between middle-IR and visible channel on haze day. From Jun. 1st to Sep. 30th, 2008, AOT observed by sun photometer (CE318) on the ground was used to validate HOT, and it had shown good coherence.

Nitrogen dioxide (NO 2 ) plays a very important role among the anthropogenic trace gases. The tropospheric NO 2 vertical column density (VCD) maps derived have been used to study many scientific applications, pollution emissions and pollutant distribution. During the 2008 Summer Olympic Games in Beijing, NO 2 is one main air pollutant which should be monitored. This paper presents the NO 2 inverse algorithm, the Differential Optical Absorption Spectroscopy (DOAS), from satellite measurements and the results using this method. The results show 1) the tropospheric NO 2 VCD in Beijing is about the same as that in other cities nearby in June, 2008; 2) from July 1, the tropospheric NO 2 VCD in Beijing decreases significantly, however, it changes little in other cities nearby; 3) the tropospheric NO 2 VCD in Beijing increases a little in August, 2008, which is much lower than that in other cities around, such as Tianjin, Tan g shan.

Operational global quantitative retrievals of aerosol have been made from Moderate Resolution Imaging Spectrometer (MODIS) data for several years by NASA EOS teams. Dark Dense Vegetation (DDV) algorithm has shown excellent competence at aerosol distribution and properties over land. In Sep. 2008, China successfully launched environmental satellite and received Charge Coupled Device (CCD) sensor data, it will provide a new way to monitor aerosol optical thickness (AOT) and distribution at a higher resolution (30m×30m). According to DDV algorithm and HJ-1-CCD camera characters, we measured different surface reflectance spectra in Beijing and Pearl River Delta areas, then ascertained NDVI value and the surface reflectance radio between HJ-1-CCD red and blue band. This paper introduces the aerosol retrieval process including lookup table establishing, cloud detection and so on; Finally, the retrieved AOTs were validated by ground measurement and compared by MODIS aerosol products.

Polarization space-borne sensor, just like POLDER (Polarization and Directionality of the Earth's Reflectances), is a new instrument devoted to the global observation of solar radiation reflected by the Earth surface-atmosphere system. It is necessary to acquire polarized information in retrieval of aerosol properties over land surface. Often the aerosol contribution is small compared to the surface, especially by covered vegetation. Atmospheric scattering is much more polarized than the surface reflectance. Using polarized information could solve the inverse problem of separating the surface and atmospheric scattering contributions. This paper presents retrieval of aerosols properties from multi-wavelength polarized measurements. The results suggest that it is feasible and possibility for discriminating the aerosol contribution from the surface in the aerosol retrieval procedure using multidirectional and multiwavelegth polarization measurements.

Cirrus clouds are known to play a key role in the Earth's radiation budget and global climate change, the radiative effects of cirrus clouds depend critically on cloud properties such as optical thickness and particle shape and size. The studies of the optical, microphysical, and physical properties of cirrus have become the popular issue. This paper simulated the bidirectional reflectance distribution function (BRDF) and bidirectional polarization reflectance distribution function (BPDF) at 1380 nm in cirrus cloudy conditions on the basis of an adding-doubling radiative transfer program. Based on the sensitivity of 1380 nm spectral reflectance and polarization reflectance on cirrus optical thickness and aspect ratio, a conceptual approach has been developed to simultaneous retrieve the particle shape and optical thickness of cirrus clouds using the remote sensing data of multi-angular total and polarized at 1380 nm.

Because of a series of complex environmental and instrumental effects, there are strip-pattern noises in images of many bands of MODIS, especially in that of Band 5. Several destriping algorithms have been used to remove the strips in MODIS images, but since they could not properly take account of physical or spectral relevance maintained in the data, the destriping results are hardly ideal. A new algorithm is proposed for the removal of strips in Band 5 images. It can locate the strips accurately so as to retain as much original information of the image as possible. Additionally, the new algorithm makes full use of the spectral correlation of multi-band remote sensed data, and can reconstruct the Band 5 value of strip-pixels based on appropriate interpolation. The validation and comparison with other algorithms indicate that, this new algorithm could remove strips perfectly and the reconstructed values have a small deviation of about 3% from the "true values".