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From the interplay of high-resolution scanning tunneling microscopy (STM) imaging/manipulation and density functional theory (DFT) calculations, we have shown that the spontaneous formation of an organometallic complex by copper–alkene interactions can be successfully achieved, where the specific molecular adsorption geometry is revealed to be the key for facilitating such interaction.

To determine the effects of minimally invasive surgery (MIS) at various stages after intracerebral hemorrhage (ICH) on perihematomal endothelin (ET)-1 levels and neurological functioning.Sixty rabbits were randomly distributed into a model control group (MC group, 30 rabbits) or a MIS group (MI group, 30 rabbits). An ICH model was established in all animals. In the MI group, ICH was evacuated by MIS at 6, 12, 18, 24, and 48 hours (six rabbits at each time point) after the ICH was established. The animals in the MC group underwent the same procedures for ICH evacuation, but with a sham operation without hematoma aspiration. All the animals were sacrificed 7 days after the ICH was established. Neurological deficit scores were determined, and the perihematomal brain tissue was removed to determine the ET-1 levels, blood-brain barrier (BBB) permeability, and brain water content (BWC).The neurological deficit scores, perihematomal ET-1 levels, BBB permeability, and BWC all decreased significantly in the MI group compared to the MC group. Performing the MIS for evacuating the ICH at 6 hours resulted in the most remarkable decreases in these indices, followed by a significant difference observed at 12 hours within the MI subgroups.Performing MIS at 6-12 hours after ICH resulted in the most significant decreases in neurological deficit scores, ET-1 levels, BBB permeability, and brain edema. The optimal time window for performing MIS for ICH evacuation might be within 6-12 hours after hemorrhage.

SummaryDepending on endoplasmic reticulum (ER) stress levels, the ER transmembrane multidomain protein IRE1α promotes either adaptation or apoptosis. Unfolded ER proteins cause IRE1α lumenal domain homo-oligomerization, inducing trans autophosphorylation that further drives homo-oligomerization of its cytosolic kinase/endoribonuclease (RNase) domains to activate mRNA splicing of adaptive XBP1 transcription factor. However, under high/chronic ER stress, IRE1α surpasses an oligomerization threshold that expands RNase substrate repertoire to many ER-localized mRNAs, leading to apoptosis. To modulate these effects, we developed ATP-competitive IRE1α Kinase-Inhibiting RNase Attenuators—KIRAs—that allosterically inhibit IRE1α’s RNase by breaking oligomers. One optimized KIRA, KIRA6, inhibits IRE1α in vivo and promotes cell survival under ER stress. Intravitreally, KIRA6 preserves photoreceptor functional viability in rat models of ER stress-induced retinal degeneration. Systemically, KIRA6 preserves pancreatic β cells, increases insulin, and reduces hyperglycemia in Akita diabetic mice. Thus, IRE1α powerfully controls cell fate but can itself be controlled with small molecules to reduce cell degeneration.

Long-term observations from the Stratospheric Sounding Unit (SSU) during 1979–2006 onboard NOAA historical polar orbiting satellites were recalibrated for climate change investigation. A two-point linear calibration equation, with cold space and an internal blackbody warm target as end-point references, was used to transfer SSU raw counts data into radiances. The warm target temperature was represented by measurements from the space side thermistor on the blackbody, and the cold space radiance was assumed to be zero. Space view corrections due to an electrical interference were applied. Intersatellite calibration was conducted simultaneously by applying calibration offsets determined from residual intersatellite biases. The recalibration reached an accuracy of 0.1–0.2 K for global means and thus is expected to improve the consistency in stratospheric temperature time series in climate reanalyses. The recalibrated SSU radiances were further adjusted to develop Version 2 of the NOAA stratospheric temperature time series. The effects being adjusted included those from changes in instrument cell pressure and atmospheric carbon dioxide concentration, viewing angle differences, and semidiurnal tides due to orbital drift. Intersatellite biases were carefully removed to ensure smooth transitions between satellite pairs. Differences from Version 1 included improved radiance calibration, improved adjusting schemes for diurnal drift and intersatellite biases, removal of time-varying cell pressure adjustment for NOAA-9 channel 1, and excluding NOAA-7 channel 2 in the time series. In addition to the final merged data set, intermediate synthetic time series corresponding to different adjustments were also created to quantify their impact on the final trend as well as its reliability and uncertainty. Excellent matching between satellite pairs, especially the 7 year overlaps between NOAA-11 and NOAA-14 during 1997–2004, in intermediate as well as the final time series provided strong evidence on the validity of adjustments and thus confidence on the resulting trends. The Version 2 global mean trends for 1979–2006 were −0.69 ± 0.18, −0.77 ± 0.15, and −0.85 ± 0.15 K/decade for SSU channels 1, 2, and 3, representing temperatures of middle stratosphere, upper stratosphere, and stratosphere-mesosphere, respectively. Among these, cooling of channel 2 was stronger and channel 3 weaker than those in UK Met Office (UKMO) data by about 1 K during the entire SSU period from 1979 to 2006. Finally, the average of the channel 1 and channel 3 anomalies in Version 2 was close to channel 2 anomalies to within 0.2 K for the entire 1979–2006 period with identical trends. This feature was found consistent with chemistry-climate model simulations.

Objective To observe the relationship between the perihematomal glutamate levels and the blood–brain barrier (BBB) permeability in a rabbit model of intracerebral hemorrhage (ICH). Methods Seventy-two rabbits were randomly divided into an intracerebral hemorrhage (ICH) model group and a normal control (NC) group, and each group of 36 rabbits was subsequently divided into 6, 12, 18, 24, 48 and 72 h groups (n = 6 each). An ICH model was induced by stereotactic injection of autologous, arterial, non-anticoagulated blood into rabbit basal ganglia. The same procedures were performed in the NC group, but blood was not injected. The rabbits were sacrificed at specific time points after the experiment began depending on their group. Perihematomal brain tissues were collected to determine glutamate levels, BBB permeability and brain water content (BWC). Results All of the assessed parameters were increased 6 hour after blood infusion and continued to gradually increase, peaking at 48 hours. Differences were observed when ICH values were compared with those of the NC group (p

To determine whether non-thermal effect exist during the process of enzyme inactivation by microwave radiation, the conformation and activity of wheat germ lipase (WGL) treated by microwaves and conventional heating were investigated, respectively. The results indicated that, when the WGL was maintained at 20 °C, its Tyr, Trp residues, the secondary and tertiary structures did not changed, even though the microwave was sustained for 1,800 s with power of higher than 80 W. While, when the temperatures were up to 45 and 60 °C, the activity of WGL decreased 60% and 100%, respectively, and the tertiary structure of WGL was totally changed by microwave at 60 °C. Moreover, the inactivation efficient of microwave radiation was about 10% more than that of conventional heating based on the thermal effects. In conclusion, microwave inactive WGL based on thermal effects rather than non-thermal effect, and was more effective than conventional heating. Practical Applications Microwave has been widely used in food thawing, drying, sterilization, enzyme inactivation and et al. In cereal industry, microwave is usually used to inactivate wheat germ lipase (WGL), which plays an important role in the storage of wheat products. However, because the effects of microwave was strongly interferes by the possible non-thermal effect and cannot be separated easily, the potential inactivation mechanism of microwave on enzyme was not clear enough to guide the inactivation process of lipase by microwave. In this study, the effects of microwave and conventional heating on the stability of WGL were investigated to detect the possibility of non-thermal effects during the inactivation process of lipase by microwave. The results make sure that, the microwave inactivated WGL based on thermal effect, rather than non-thermal effect. Thus, we can focus on the factors that influence the heating efficiency to improve the effect of inactivation of WGL or other lipase by microwave.

Given the fact that Cross-track Infrared Sounder (CrIS) and the Visible Infrared Imaging Radiometer Suite (VIIRS) are currently onboard the Suomi National Polar-orbiting Partnership (Suomi NPP) satellite and will continue to be carried on the same platform as future Joint Polar Satellite System (JPSS) satellites for the next decade, it is desirable to develop a fast and accurate collocation scheme to collocate VIIRS products and measurements with CrIS for applications that rely on combining measurements from two sensors such as inter-calibration, geolocation assessment, and cloud detection. In this study, an accurate and fast collocation method to collocate VIIRS measurements within CrIS instantaneous field of view (IFOV) directly based on line-of-sight (LOS) pointing vectors is developed and discussed in detail. We demonstrate that this method is not only accurate and precise from a mathematical perspective, but also easy to implement computationally. More importantly, with optimization, this method is very fast and efficient and thus can meet operational requirements. Finally, this collocation method can be extended to a wide variety of sensors on different satellite platforms.

The Cross-track Infrared Sounder (CrIS) on the newly-launched Suomi National Polar-orbiting Partnership (Suomi NPP) is a Fourier transform spectrometer that provides soundings of the atmosphere with 1305 spectral channels, over 3 wavelength ranges: LWIR (9.14 - 15.38 μm); MWIR (5.71 - 8.26 μm); and SWIR (3.92 - 4.64 μm). An accurate spectral and radiometric calibration as well as geolocation is fundamental for CrIS radiance Sensor Data Records (SDRs). In this study, through inter- and intra-satellite calibration efforts, we focus on assessment of NPP/CrIS post-launch performance. First, we compare CrIS hyperspectral radiance measurements with the Atmospheric Infrared Sounder (AIRS) on NASA Earth Observing System (EOS) Aqua and Infrared Atmospheric Sounding Interferometer (IASI) on Metop-A to examine spectral and radiometric consistence and difference among three hyperspectral IR sounders. Secondly, an accurate collocation algorithm has been developed to collocate high spatial resolution measurements from the Visible Infrared Imager Radiometer Suite (VIIRS) within each CrIS Field of View (FOV). We compare CrIS spectrally-averaged radiances with the spatially-averaged and collocated pixels from the VIIRS IR channels. Since CrIS and VIIRS are onboard on the same satellite platform, the intra-satellite comparison will allow examining the radiometric difference between CrIS and VIIRS with scene temperatures, scan angles, and orbital position. In addition, given a high spatial resolution of VIIRS channels, the VIIRS-CrIS comparison results can access geolocation accuracy of CrIS that have relatively large FOVs (14 km at ndair) using high resolution VIIRS pixel (375m or 750m at nadir).

The Crosstrack Infrared Sounder (CrIS) is a Michelson type Fourier Transform Spectrometer flying on-board the SUOMI NPP satellite that was launched into orbit on October 28th 2011. CrIS measures the Top of Atmosphere (TOA) infrared radiance. Calibration and validation activities at NOAA-STAR includes: 1) The double difference of CrIS field of view (FOV) intercomparison using the Community Radiative Transform Model (CRTM) where the FOV are consistent to 0.05K or better, 2) Simultaneous nadir overpass (SNO) radiance comparison of CrIS with IASI with 0.2K agreement over the window channels,3) Top of atmosphere radiance comparison of the measured with the CRTM with an agreement of 0.4K or better over the window channels, 4) Double difference of CrIS vs IASI with an agreement of 0.3K over the window channels., 5) Long term monitoring and trending of 55 parameters, 6) Geolocation assessment using VIIRS where CrIS now has an estimated accuracy of 1 Km. Calibration and validation of the CrIS SDR is essential because its radiance product is assimilated by the NWP algorithm leading to weather forecasting.

To Die For The unfolded protein response (UPR) adjusts the protein folding capacity of the endoplasmic reticulum (ER) to match demand. UPR signaling requires IRE1α, an ER transmembrane kinase-endoribonuclease (RNase) that becomes activated by unfolded protein accumulation within the ER and excises a segment in XBP1 messenger RNA (mRNA) to initiate production of the homeostatic transcription factor XBP1s. However, if ER stress is irremediable, sustained IRE1α RNase activity triggers cell death. Severe ER stress activates the protease Caspase-2 as an early apoptotic switch upstream of mitochondria. However, the molecular events leading from the detection of ER stress to Caspase-2 activation are unclear. Upton et al. (p. 818 , published online 4 October) now report that IRE1α is the ER stress sensor that activates Caspase-2, and does so through a mechanism involving non-coding RNAs. Under irremediable ER stress, IRE1α's RNase triggers the rapid decay of select microRNAs that normally repress translation of Caspase-2 mRNA, rapidly increasing Caspase-2 levels as the first step in its activation.

As a complex nonlinear gray system, the safety of uranium waste rock heap is affected by variety of factors, such as rock mass integrity, nuclear radiation, vegetation cover and so on. In order to rationally evaluate and predict its environmental safety, based on the theory of gray correlation analysis (GCA) method, the hybrid weight gray correlation analysis (HWGCA) method has been proposed, which combines the analytic hierarchy process (AHP) and entropy weight method (EWM) to calculate the hybrid weight. By using the hybrid weight to calculate the gray correlation grade, we then can evaluate and predict the environmental safety grade of the gray system. The HWGCA method has inherited the advantages of AHP and EWM; the subjective arbitrariness shortcomings in the analysis of environment safety could be avoided, and it can improve the evaluation accuracy and reliability. In this article, we have selected three types uranium waste rock heaps (UWRH) from one uranium mine in Sichuan province to evaluate its environmental safety using the HWGCA method. We used the three-scale AHP and EWM to calculate the hybrid weight, and then calculate the correlation coefficients of each factor. The detailed calculation process is shown in this paper, and the evaluation results and site survey results are consistent.

The objective of this study was to observe the pathophysiological time window of performing minimally invasive procedures for the intracerebral hematoma evacuation. Thirty-six rabbits were randomly placed in either a normal control group (NC group, 6 rabbits), a model control group (MC group, 6 rabbits) or a minimally invasive group (MI group, 24 rabbits). A model of intracerebral hemorrhage (ICH) was established in the MC and MI groups. In the MI group, the intracerebral hematoma was evacuated by stereotactic minimally invasive procedures over 6 h (6 rabbits), 12 h (6 rabbits), 18 h (6 rabbits) and 24 h (6 rabbits), following successful induction of ICH. All of the animals in each group were sacrificed 48 h after the successful induction of ICH. Perihematomal brain tissues were removed to determine the glutamate level, BBB permeability and brain water content (BWC). The perihematomal glutamate level, BBB permeability and the BWC in the MI group were significantly decreased compared with those of the MC group. Performing minimally invasive procedures for evacuation of ICH in 6 h showed the most remarkable decrease of the glutamate level, BBB permeability and BWC, followed by a significant difference observed at 12 h within the MI subgroups. Performing minimally invasive procedures in early stages after ICH for the hematoma evacuation could decrease the perihematomal glutamate level, BBB permeability and BWC significantly. The pathophysiological time window of minimally invasive procedures for hematoma evacuation might be 6–12 h after hemorrhage.

To observe the effects of minimally invasive procedures for the evacuation of intracerebral hematomas on perihematomal ET-1 expression and their correlation with blood–brain barrier (BBB) permeability. Forty-five rabbits (2.8–3.4 kg body weight) were randomly divided into a normal control group (NC group, 15 rabbits), a model control group (MC group, 15 rabbits) and a minimally invasive group (MI group, 15 rabbits). A model of intracerebral hemorrhage (ICH) was prepared in the MC and MI groups by infusing autologous arterial blood into the rabbits’ brains; the same procedure was also performed in the NC group but without infusing blood into the rabbits’ brains. The intracerebral hematomas were evacuated by a stereotactic procedure in the minimally invasive group 6 h after the model was established. The neurological functions, ET-1 expression and the perihematomal BBB permeability were determined and analyzed in all of the animals. The number of endothelial cells with ET-1-positive expression and the perihematomal BBB permeability significantly increased 1, 3, and 7 days after the ICH model was prepared successfully, as compared to the NC group. In the MI group, however, both measurements decreased markedly compared with the MC group at the same time point. A positive correlation between the number of endothelial cells with ET-1-positive expression and BBB permeability was observed. Increased BBB permeability might be associated with perihematomal ET-1 levels. Minimally invasive procedures for the evacuation of intracerebral hematomas could significantly decrease BBB permeability in perihematomal brain tissues, likely by reducing the production of ET-1.

Prx4 (peroxiredoxin 4) is the only peroxiredoxin located in the ER (endoplasmic reticulum) and a proposed scavenger for H2O2. In the present study, we solved crystal structures of human Prx4 in three different redox forms and characterized the reaction features of Prx4 with H2O2. Prx4 exhibits a toroid-shaped decamer constructed of five catalytic dimers. Structural analysis revealed conformational changes around helix α2 and the C-terminal reigon with a YF (Tyr-Phe) motif from the partner subunit, which are required for interchain disulfide formation between Cys87 and Cys208, a critical step of the catalysis. The structural explanation for the restricting role of the YF motif on the active site dynamics is provided in detail. Prx4 has a high reactivity with H2O2, but is susceptible to overoxidation and consequent inactivation by H2O2. Either deletion of the YF motif or dissociation into dimers decreased the susceptibility of Prx4 to overoxidation by increasing the flexibility of Cys87.

Previous studies have indicated that ERp44 inhibits inositol 1,4,5-trisphosphate (IP(3))-induced Ca(2+) release (IICR) via IP(3)R(1), but the mechanism remains largely unexplored. Using extracellular ATP to induce intracellular calcium transient as an IICR model, Ca(2+) image, pull down assay, and Western blotting experiments were carried out in the present study. We found that extracellular ATP induced calcium transient via IP(3)Rs (IICR) and the IICR were markedly decreased in ERp44 overexpressed Hela cells. The inhibitory effect of C160S/C212S but not C29S/T396A/ΔT(331-377) mutants of ERp44 on IICR were significantly decreased compared with ERp44. However, the binding capacity of ERp44 to L3V domain of IP(3)R(1) (1L3V) was enhanced by ERp44 C160S/C212S mutation. Taken together, these results suggest that the mutants of ERp44, C160/C212, can more tightly bind to IP(3)R(1) but exhibit a weak inhibition of IP(3)R(1) channel activity in Hela cells.

Pyrolytic tire char was used to prepare activated carbon by steam. The effects of such factors as pretreatment, activation temperature, rate of water vapor and activation time upon the adsorption properties of AC have been investigated. The prepared activated pyrolytic tire char were characterized by N 2 physisorption, XRD, FT-IR and elemental analyses. The optimum process parameters and listed as follows: activation temperature 800°C, the rate of water vapor 2g/min, activation time 2h.

[1] Quantifying the radiometric difference and creating a calibration link between Atmospheric Infrared Sounder (AIRS) on Aqua and Infrared Atmospheric Sounding Interferometer (IASI) on MetOp are crucial for creating fundamental climate data records and intercalibrating other narrowband or broadband satellite instruments. This study employs two different methods to assess the AIRS and IASI radiance consistency within the four Geostationary Operational Environmental Satellite (GOES) imager infrared channels (with central wavelengths at 6.7, 10.7, 12.0, and 13.3 μm) through a period of 2 years and 9 months. The first method employs the differences of AIRS and IASI relative to the GOES observations sampled in the tropics to indirectly track the AIRS and IASI radiance differences. The second approach directly compares AIRS and IASI in the polar regions through the simultaneous nadir overpass observations. Both methods reveal that AIRS and IASI radiances are in good agreement with each other both in the tropics and in the polar regions within GOES imager channels used in this study, while AIRS is found to be slightly warmer than IASI by less than 0.1 K.

Based on the data obtained from the exploration for coal and coalbed methane, the characteristics of coalbed methane reservoir in the North Qinshui Basin is discussed systematically. The description on the reservoir property (including coalbed geometry, gas content, adsorption, physical property of the coal, reservoir pressure etc.) and controlling factors (including the structure, sealing condition, Hydrogeological condition, and karst collapse column) of the coalbed methane reservoir show that coalbed methane accumulation of research area is the result of reasonable effective disposition of geologic feature and geological processes controlled by extrinsic geological action processes. Gas saturation overall low is mainly caused by the bearing strata after uplift re-subsidence; the coalbed methane accumulation is controlled by the structure, the roof and floor of coal sealing condition; the groundwater stagnant zone is the favorable area for coalbed methane accumulation; and karst collapse columns and partial opening faults are major factors for coalbed methane leading to depletion.

In order to meet the needs of 3D seismic image filtering, the method of 3D anisotropic diffusion filtering has been studied. And the relationship between the eigenvalues of structure tensor and the stratum structure has been analyzed in detail. By using structure tensor, extracted the local structure of 3D seismic image, and using the improved coherent enhancement diffusion method, designed eigenvalues of diffusion tensor, and constructed the diffusion tensor to control the diffusion rate of three main orientation. And anisotropic diffusion filter algorithm and program has been designed. The results of 3D theory model test and real seismic data processing has verified the correctness and effectiveness of this method. And the filtering results demonstrate its efficiency to remove incoherent noise as well as to enhance the continuity of seismic events and geologic sediments. This diffusion filter can improve the quality of seismic data wholly.

To resolve the problem of reclaiming residual heat of the flue gas for thermal organic media furnace with coal as fuel, a technique project of reclaiming residual heat of the flue gas using heat pipe technology is put forward, and the technology of heat exchanger network is optimized. 1.25MPa steam produced by the heat pipe steam generator reclaiming residual heat of the flue gas can supply supplement steam of the rapid installation steam boiler, and the boiler operation time can be reduced and the energy can be saved. The heat pipe air pre-heater further recycles residual heat of the flue gas, preheating up the air from the normal temperature to 130°C or so, as heating furnace's oxidizing air. And the efficiency of heating furnace can be improved. The project application example indicated that the economic benefit of the system of reclaiming residual heat of the flue gas using heat pipe technology is the more remarkable than that of the traditional tube-shell air pre-heater.

Piezoelectric Disc Stack Acoustic Transducer was mainly made of piezoelectric ceramic discs, which were bonded together concentrically with epoxy resin. Because of piezoelectric effect and the anisotropy characteristics of piezoelectric ceramic, when electronic signals were put on the power-lead electrodes in the thickness direction, the radial vibration generated and could be measured. In this article, the vibration model of the disc stack transducer was analyzed with the method of finite-element method. Transducer models were established with ANSYS 10.0 both in air and in water. The relationship between the transducer work frequency and its structure dimension was acquired. According to the radial vibration features and the finite element method simulation results, the structure of the acoustic transducer was optimized. Besides that, a series of experiments including impedance analysis and laser scanning vibration on the transducer sample was carried out to verify the simulation results. All the results conformed well.

Modern reanalysis datasets provide us with the best available four-dimensional, homogeneous datasets for studying the climate and weather systems and for possible validation of climate models. In order to have confidence in the use of reanalysis data for the above-mentioned studies, it is important to see how they compare with a common dataset with high data quality and to understand any discrepancies among them. In this study, the radiance measurements from the Atmospheric Infrared Sounder (AIRS) on NASA Aqua are used to assess the data quality of reanalysis datasets, including NASA's Modern Era Retrospective-analysis for Research and Applications (MERRA), European Centre for Medium-Range Weather Forecast's ERA-Interim Reanalysis, Japanese 25-year Reanalysis (JRA-25). Particularly, we focus on the spectral signature regions that are sensitive to stratosphere temperature and upper troposphere water vapor. The preliminary results on are presented.

1-3-2 composite is made of 1-3 composite and ceramic base. The influence of piezoelectric phase volume fraction and composite aspect (thickness/width) on resonance characteristic of square 1-3-2 piezoelectric composite plate has been researched in ANSYS. The resonance frequency of 1-3-2 composite samples was investigated. The result shows that when the volume fraction of ceramic rods is about 0.46 in the 1-3-2 composite model of ANSYS, The result of simulation will be perfectly close to the data of experiment. The contour mode 8 among contour -extensional modes would disturb the thickness mode when the ratio of thickness to width is more than 0.3.

This paper presents a novel piezoelectric dynamic pressure sensor, it consists of sensing element and inner preamplifier. The piezoelectric unimorph was used as sensing element. The charge amplifier with high input impedance was used to decrease the impedance of the unimorph and amplify the sensing signal. The properties of sensor were calculated and measured. The measured results show a sensitivity of 0.41mV/Pa, a good agreement with theoretic calculation, a pressure range of 1kPa, a linearity of 1% F.S, a response time of 40µs and a nature frequency of 8.5kHz. Compared with present congeneric sensors, it exhibits high sensitivity, simple structure and low cost.

This paper reports the preparation method of PbTiO3–P(VDF/TeFE) piezoelectric composites, analyzes and measures the density and electrical properties of the composites. Figure of merit of the material (dhgh) was 1500×10−15 m2/N. Using the composite as sensing material, a good piezoelectric sensor was designed.

Summary: High-throughput RNA sequencing (RNA-seq) is rapidly emerging as a major quantitative transcriptome profiling platform. Here, we present DEGseq, an R package to identify differentially expressed genes or isoforms for RNA-seq data from different samples. In this package, we integrated three existing methods, and introduced two novel methods based on MA-plot to detect and visualize gene expression difference. Availability: The R package and a quick-start vignette is available at http://bioinfo.au.tsinghua.edu.cn/software/degseq Contact: xwwang@tsinghua.edu.cn; zhangxg@tsinghua.edu.cn Supplementary information: Supplementary data are available at Bioinformatics online.

Global Space-based Inter-Calibration System (GSICS) is a critical space component of Global Earth Observation System of Systems (GEOSS) that provided users with high-quality inter-calibrated satellite measurements. As part of the GSICS, imaging instruments on geostationary (GEO) satellites have been inter-calibrated with hyperspectral instrument Atmospheric Infrared Sounder (AIRS) and Infrared Atmospheric Sounding Interferometer (IASI) on Low Earth Orbit (LEO) satellites. This paper reports the GSICS GEO-LEO inter-calibration at NOAA/NESDIS, for GOES-11/12 with AIRS (since January 2007) and IASI (since June 2007), and of METEOSAT-7/8/9, MTSAT-1R, and FY-2C with AIRS and IASI since August 2008. Major components of the operation are reviewed, including algorithm development, data processing, product generation, results dissemination, and selected inter-calibration examples. The preliminary results of the GSICS correction show that the fully functioning GSICS is a powerful tool to monitor instrument performance, to correct sensor bias, and to diagnose the root cause of calibration anomalies.

The geostationary meteorological satellites (GEO), such as Geostationary Operational Environmental Satellite (GOES), are susceptible to a calibration anomaly around local midnight of the sub-satellite point. A counter measure, the Midnight Blackbody Calibration Correction (MBCC) currently exists at operational level. In this study, the MBCC performance on GOES-11 satellite is characterized with the help of Global Space-based Inter-Calibration System (GSICS) data sets. Results from the comparison of coincident and collocated GSICS-based GOES-11-AIRS data pairs, corresponding to two and half year period from January 2007 through June 2009, reveal that "mid-night residuals" in brightness temperatures persist in all of the GOES-11 Infra-Red (IR) channels, in spite of MBCC. The GOES-11 split window channels (channels 4 and 5) consistently showed significantly large negative (GOES-11-AIRS) biases often reaching values of -1. 5 K or less while the short wave Infra-Red (SWIR) channel (channel 2) produced relatively smaller negative biases (~ -0.3 K or less). Interestingly, the water vapor IR channel (channel 3) exhibits a different pattern from rest of the channels in which consistently opposite biases with small positive (GOES-11-AIRS) difference values (~ 0.3 K or less) could be observed. The reason for the differential behavior of GOES-11 channel 3 is yet to be understood, while it is hypothesized that this might be linked to the convolution algorithm used for matching the AIRS data spectrally with those from GOES water vapor channel. The amount of midnight residuals is shown to have a consistent seasonal dependency, which gets repeated year after year, for the period considered in the analysis.

Using the chamber filled with the compressed silica oil, the variety of the dielectric and hydrostatic piezoelectric properties of 1-3-2 piezoelectric composite, which is a novel composite with PZT and epoxy, is studied in hydrostatic pressure surrounding. The 1-3 composite produced together with 1-3-2 composite by the same technics is measured in the same experiments with 1-3-2 composites. And the results have been compared between the 1-3 and 1-3-2 composites. The comparisons show that 1-3-2 composite has more mechanical stability than 1-3 composite when hydrostatic pressure varying from 0MPa to 10Mpa. The temperature stability is measured in a thermostat which provided the environment temperature varying from −60°C to 90°C. The results also show that 1-3-2 composite has more temperature stability than 1-3 composite.

The potential use of the inter-calibration results to optimally integrate and merge data from GOES 11 and 12 imagers to create consistent, seamless global products is explored in this study. There are three steps involved, including 1) limb correction; 2) tying GOES measurements to IASI; and 3) resolving the SRF-difference-induced biases. We first use the IASI hyperspectral measurements on the polar-orbiting MetOp-A satellite to access the calibration accuracy of water vapor channels on the GOES-11 and GOES-12 imagers with one year of match-up data. The simultaneous nadir observations with homogeneous scenes from IASI and GOES imagers are spatially collocated. The IASI spectra are convolved with the GOES Imager SRFs to compare with GOES Imager observations. Assuming that IASI is well calibrated and can be used as a radiometric reference standard, the GOES imager water vapors were found to have an estimated calibration accuracy of less than 0.3 K (with a standard deviation of less than 0.2 K) at the BT range 240-260K relative to IASI, which meets the GOES imager design specification (1.0 K calibration accuracy for infrared channels). In a second step, merging GOES-11 and GOES-12 water vapor channel through IASI is investigated. A linear relationship is proposed. An example of creating water vapor composite image from the GOES-11 and GOES-12 to resolve their observational discrepancy is presented step-by-step. This study further demonstrates the usefulness of employing high spectral resolution radiance measurements to accurately assess broadband radiometer calibration and create the calibration link between instruments. In the future, we will extend this method to other satellites.

There are significant challenges in making the observations from HIRS (High Resolution Infrared Radiation Sounder) on the 13+ satellites consistent for climate change detection. It is well known that for HIRS, the inter-satellite biases are significantly affected by differences in the spectral response functions (SRF) between instruments, since they often lead to observations of the atmosphere at different altitudes. The SRF dependent biases are further mixed with other effects such as the diurnal cycle due to observation time differences and orbital drifts, blackbody emissivity, and calibration algorithms. In this study, the IASI (Infrared Atmospheric Sounding Interferometer) observations are used to calculate the HIRS radiances by convolving the IASI observed radiances with the SRF of each HIRS model across different climate zones in different seasons, which separates the SRF induced intersatellite biases from other factors. It is found that the calculated radiance ratios using IASI observations for the HIRS satellite pairs form bell shaped curves that vary with the HIRS model, channel, as well as climate zones. Understanding the characteristics of these bell curves are essential for resolving the SRF dependent intersatellite biases and the development of fundamental climate data records from HIRS.

Various types of defect may be formed in girth welds of long-distance pipeline in the process of welding. They are hidden dangers to pipeline transportation safety. Currently, ultrasonic phased array instrument is commonly adopted for quick automatic positioning and quantitative analysis of flaws in the girth weld after welding. But as for qualitative analysis – flaw classification, traditional manual identification method is still used. By traditional method, human-made error is easily introduced and classification result is depended on the detection experiences of the inspecting person. To overcome these deficiencies, a new method combined second generation wavelet transform (SGWT) with Radial Basis Function neural network (RBFN) is proposed in this paper, realizing automatic flaw classification and reducing human factors impaction. SGWT is ideally matched local characteristics of the flaw signal, improving both the computational speed and flaw classification efficiency. Then, based on the “energy-status” feature extraction method and the above SGWT analysis, feature eigenvectors of the flaw signals are extracted, training the following RBFN. And then when the feature of any flaw is extracted, it can be recognized by the network. The output of the network is the type of the input flaw signal, realizing automatic flaw classification. Finally, an ultrasonic phased array inspection system is described. The system is integrated with automatic flaw detection and classification. Experiments are tested on a long-distance pipeline girth weld block with artificial defects in it. The results validate that the proposed method is efficient, which is helpful to increasing inspection speed and reliability of flaw inspection for long-distance pipeline girth welds.Copyright © 2008 by ASME

Static pressure method and dynamic pressure method were commonly used in pipeline leak detection. Advantages and disadvantages of the two methods were analyzed and a dynamic pressure sensor was designed for long-range oil and gas transmission pipeline. In order to improve its performance, experiments of circuit simulation was carried out on the main part of the sensor. Application experiments show that the dynamic pressure sensor is more suitable for pipeline leak detection on occasion that internal pressure changes rapidly, and contribute to increase positioning accuracy.

Though ultrasonic phased array technology is more efficient than traditional manual ultrasonic testing method, automatic flaw classification is a challenge and still hasn’t been well solved. Whether the representative features can be extracted from each type of ultrasonic flaw signal is a key to influencing the accuracy rate of automatic flaw classification. In this paper, second generation wavelet transform (SGWT) is proposed as a flaw feature extraction method, having the advantages of high computation speed, simple structure and occupying less memory. After introducing the principle of SGWT, the SGWT-based feature extraction algorithm is analyzed. Separability measure based on Euclidean distance is introduced as the evaluation criterion to assess flaw feature extraction performance. For comparison, first generation wavelet packet transform (WPT), a common feature extraction method, is also adopted to extract flaw feature. The experiment result is indicated that the classification performance of SGWT-based feature extraction algorithm is improved than WPT-based feature extraction algorithm, and the classification speed of the former is almost two times of the latter, which is valuable for automatic flaw detection and classification of pipeline girth weld.Copyright © 2008 by ASME

A dynamic pressure sensor, which can be used to sample the long oil and gas pipeline leakage signal, is developed. Performances of the sensor are improved by using circuit simulation tools. Application experiments of the designed sensor show that the dynamic pressure signal is better suited for pipeline leak detection of pipeline internal pressure rapid changes occasions, and the using of the designed sensor can improve positioning accuracy.Copyright © 2008 by ASME

Accurate and precise satellite radiance measurements are important for data assimilations in numerical weather prediction models and climate change detection. Given the high-resolution spectral IASI measurements with high data quality, it allows us to assess the radiance measurements of 'heritage' instruments that share the same spectral region with IASI. In this study, we demonstrate the utility of the IASI radiances to evaluate the AVHRR IR channel observations. The IASI spectral radiances are convolved with the AVHRR SRFs (Spectral Response Functions) to produce the IASI-convolved AVHRR radiances. The co-registered AVHRR pixels inside each IASI pixel are averaged to compare with IASI. We analyzed one-orbit data on 21 June 2007, and preliminary comparison has been performed. Statistically, the temperature observed from AVHRR channels 4 and 5 is slightly warmer than IASI. The mean BT difference (IASI minus AVHRR) is -0.35K for channels 4 and -0.16 K for channel 5 with a standard deviation of 0.5K. The BT difference between IASI and AVHRR IR channels is scene-temperature dependent for both channels 4 and 5, possibly caused by the nonlinearity of detector. Both AVHRR Channel 4 and channel 5 show slightly symmetric dependence on scan angle with maximum differences of approximately ~0.2 K (AVHRR warmer than IASI) at both ends of the scan (with respect to the difference at nadir). However, the root cause of the bias still needs to be investigated by analyzing more datasets.

ERp44 mediates thiol-dependent retention in the early secretory pathway, forming mixed disulphides with substrate proteins through its conserved CRFS motif. Here, we present its crystal structure at a resolution of 2.6 A. Three thioredoxin domains—a, b and b′—are arranged in a clover-like structure. A flexible carboxy-terminal tail turns back to the b′ and a domains, shielding a hydrophobic pocket in domain b′ and a hydrophobic patch around the CRFS motif in domain a. Mutational and functional studies indicate that the C-terminal tail gates the CRFS area and the adjacent hydrophobic pocket, dynamically regulating protein quality control.

Negative pressure wave (NPWs) technique is an effective method for oil leakage detection and location. However, conventional negative pressure wave technology failed to be applied to leakage location in China directly. China’s crude oil has to be transmitted over heating because of its high viscosity, high wax and high solidifying point. In this paper, conventional location method of instantaneous pressure wave was analyzed and techniques were developed to overcome the defects. Since temperature of the oil would drop continuously during transmission, temperature drop influence on physical characteristics of the crude oil and propagation velocity of pressure wave was studied in detail. In order to achieve high precision, wavelet transform algorithm was adopted to define inflexion of negative pressure wave when it propagates along the pipe, and wavelet threshold denoising technique was used to separate the characteristic inflexion of negative pressure wave when calculating the leak position. The problem of false alarms was solved by application of eigenvector indexes method. On the basis of that, a new oil leakage detection and location system was developed for hot oil transmission pipeline. In China, SCADA (supervisory control and data acquisition) system was installed on most oil transmission pipeline to monitor operational parameters for long range crude oil or product oil pipeline. Because it acquires pipeline operational parameters from the existing SCADA system, the cost and complexity of the new system was greatly reduced. The earliest leak detection and location system which installed on a hot oil transmission pipeline in PetroChina 5 years ago is still working well. It responds to leakage (1.5% of the total fluid) within 2 minutes and location error is less than 2% of the pipeline length between the two stations.Copyright © 2006 by ASME

A new distributed optical fiber pipeline leakage pre-warning system based on the principle of Mach-Zehnder optical fiber interferometer and the method of its signal analysis are proposed in this paper. In this pre-warning system, an optical cable is laid in parallel with the pipeline in the same ditch and three single mode optical fibers in the optical cable build up the distributed micro-vibrant measuring sensor. Leakage and other abnormal events can be detected by the sensor in real-time and can be identified by using an “energy-pattern” method based on the wavelet packet analysis. The position of the leak point can be obtained by calculating the value of time delay of the two measuring signals through a correlation algorithm. This system detects various oil and gas pipeline leakages, and is especially suited for micro-leakage. At the end of this paper, experimental data obtained on oil field and the result of the signal analysis are presented. The data and the result of the signal analysis show that the measuring sensitivity and location precision of detecting leakage are improved when this technology is adopted, and abnormal events can be efficiently identified.

Due to large repair workload and cost, the detection of coating has a great guidance to a major overhaul of buried pipelines. Direct current voltage gradient (DCVG) and close interval potential survey (CIPS) techniques have already been widely used in this area and the theories are introduced in this paper. Based on the above two detection principles, a set of detection instrument for coating defects of buried pipelines is developed, and the detailed hardware and software designs of the instrument is also provided. In this instrument, pipe/soil potential is used to detect coating defects and IR drop (the product of soil current and resistance) is eliminated during potential measurement using instantaneous CP (cathode protection) current cut method. The detection results saved in Flash can be displayed on LCD of the instrument or transferred to the computer for graph plotting. Through the field application examples, it is indicated that the device designed in this article has a very high precision in defects positioning and a broad prospect of application.Copyright © 2006 by ASME

Wavelet package and neural network are used to recognize the characteristics of pipeline leakage acoustic signals. Acoustic signals produced by pressure variation of pipelines can be detected by the acoustic sensors installed on the pipelines. The detecting accuracy can be increased with recognizing the acoustic signals correctly. The method to detect acoustic signals by combining the wavelet package and neural network is introduced in this paper. The signal is decomposed with wavelet package firstly, then the decomposed coefficients in each frequency band are obtained through reconstruction. As a result, the parameters of the new sequences reconstructed on every decomposed node are acquired, and then these parameters are input to BP neural network to recognize the fault reason intelligently. At the end of the paper, field experiment data and their analyzed results are studied. The experimental results are provided to show that the proposed method can increase the accuracy efficiently.Copyright © 2006 by ASME

[1] This study uses ICESat/GLAS instantaneous observations from 29 September to 18 November 2003 to investigate cloud overlap statistics between 10°S–20°N. The results show that 75.1% of profiles detect clouds: 46.5% are single layer and 28.6% multilayer clouds (cloud layers are separated by 0.5km). Using a definition of cloud type based on cloud heights and laser attenuation information, cloud overlap statistics are derived by analyzing 96.4% of the cloudy profiles. The most frequent overlap occurs between cirrus clouds and boundary layer clouds, which accounts for 31.88% of boundary clouds. 23.8% of deep convection has overlying cirrus clouds. We find that differences exist between the cloud overlap fraction from the GLAS observations and one calculated from the random overlap assumption commonly used by climate models.