Mapping rice extent and cropping scheme in the Mekong Delta using Sentinel-1A data

Synthetic aperture radar (SAR)-based multi-temporal backscatter analysis is a common approach that has been widely used for rice mapping. Co-polarized C-band microwave backscatter (HH or VV) and the co-polarization ratio (HH/VV) are the most commonly used data sets for rice mapping due to their high data availability while the utilization of cross-polarized backscatter (HV or VH) has received less attention. In this study, Sentinel 1A time series – acquired in the dual-polarized (VV/VH) Interferometric Wide (IW) swath mode during the spring growing season (October 2015 to March 2016) in the Mekong Delta – were used to analyse the relationship between the growing cycle of rice plants and the temporal variation of SAR backscatter at different polarizations. Results show that VH backscatter is more sensitive to rice growth than VV backscatter. Several vegetation phenological parameters including beginning date, heading date and the length of the growing season were extracted from the VH backscatter time series. A decision tree approach was applied to delineate rice-cultivated areas based on seasonal phenological parameters. The classification result was validated against a 2015 land use map. The overall classification accuracy is 87.2% (kappa coefficient – κ = 0.71). In addition, the SAR-derived rice area was compared against ground statistical data at the provincial level (coefficient of determination R² = 0.98).     

Modelling and correcting azimuthal anisotropy in Sentinel-1 backscatter data

Sentinel-1 backscatter data – acquired in dual-polarized (VV/VH) Interferometric Wide (IW) swath mode – show an azimuth angle dependency. The orientation of the tangential plane of the surface observed can alter the backscatter differently depending on the azimuth angle of the viewing geometry. In this study, two years of Sentinel-1 backscatter data over Western Europe have been investigated to show that the azimuthal anisotropy of backscatter is mainly caused by the orientation of the topography’s slope. The SRTM-3 digital elevation model (DEM) is used to describe the azimuthal anisotropy in the Tyrolean Alps and in addition, an algorithm is presented to take into account the azimuthal dependency by calculating correction parameters for each relative orbit of Sentinel-1.     

Best practices for the reprojection and resampling of Sentinel-2 Multi Spectral Instrument Level 1C data

The standard geolocated Sentinel-2 Multi Spectral Instrument (MSI) L1C data products are defined in spatially overlapping tiles in different Universal Transverse Mercator (UTM) map projection zones. Best practices for reprojection and resampling to properly utilize and benefit from the L1C data format are presented. Three sets of 10 m Sentinel-2 L1C data acquired in the same orbit at different latitudes are examined to illustrate and quantify (a) the spatial properties of the L1C data and provide insights into the occurrence of overlapping tiles and overlapping tiles defined in different UTM zones from the same MSI swath, (b) the geometric implications of resampling and reprojection approaches that consider only the data from one L1C tile and not the data from other tiles in the overlap region that are defined in different UTM zones and (c) a recommended approach that considers all the overlapping L1C tile data and is shown statistically and qualitatively to improve the geometric fidelity of the reprojected resampled L1C data.     

Feasibility of using signal strength indicator data to estimate soil moisture based on GNSS interference signal analysis

The use of multipath signals to estimate soil moisture is an important application of Global Navigation Satellite System (GNSS) reflectometry. In most studies the data used to estimate the soil moisture are raw signal to noise ratio (SNR) data. However, the SNR data are only regarded as auxiliary data used to determine the quality of signal in most of the widely distributed Continuous Operational Reference System (CORS) receivers. So SNR data are generally ignored and unavailable. Fortunately, the GNSS receivers output the standard data format as Rinex, where the Signal Strength Indicator (SSI) is recorded as alternative data to SNR. This study aims to investigate the feasibility of soil moisture estimation based on SSI data. An experiment was conducted to estimate SSI phase and record the in situ soil moisture data for comparison. Then the relationship between the phase and soil moisture is determined by 44 days SSI data processing. Finally, the relationship is used to further estimate soil moisture with 36 days data. Experimental results show the correlation coefficient between the SSI phase and in situ soil moisture is approximately 0.7, and that the root mean square estimation error of soil moisture is lower than 9.9%. Results demonstrate the feasibility of using SSI data to estimate soil moisture.     

Detection of sea-surface wind patterns associated with convective systems and their evolution using a combination of Sentinel-1 and Radarsat-2 imagery

ABSTRACT

Synthetic Aperture Radar (SAR) can detect wind patterns induced by the Convective Systems (CS) downdraughts hitting the sea surface due to their high spatial resolution and large swath. Additionally, the combination of two successive SAR images (Sentinel-1 and Radarsat-2) with appropriate observation time delays may enable the observation of wind pattern evolution. The corresponding METEOSAT-10/11 infrared images to the SAR ones are used for the detection of deep convective clouds that are potentially associated with wind patterns. The current paper investigates two cases of time delays (1-minute and 5-minute) between two satellites. The estimated wind speeds by CMOD5.N on Sentinel-1 and Radarsat-2 images are almost the same for the background wind areas. However, the intensity of wind patterns on Radarsat-2 images (acquired 1 and 5 minutes later) is decreased, possibly due to a change of downdraught intensity according to observation time. In the 1-minute delay case, the drop of wind intensity is mainly observed for the intense spots (20–25 m s^?1), while in the 5-minute delay case, it is noticed for both intense and moderate (10–15 m s^?1) convection spots. The intensity of the high-wind convection spots decreases more quickly since the associated convective-scale downdraughts reach the sea surface more rapidly.     

Bioremediation of cadmium-contaminated paddy soil using an autotrophic and heterotrophic mixture

Cadmium (Cd) pollution poses a serious risk to human health and ecological security. Bioremediation can be a promising and effective remediation technology for treating Cd contaminated soils. In this study, seven heterotrophic strains were isolated from Cd contaminated soil and 7 autotrophic strains were isolated from acid mine drainage. Cd removal efficiencies were compared after leaching with autotrophic bacteria (Att-sys), heterotrophic isolates (Htt-sys) and cooperative leaching systems (Co-sys) in laboratory agitating reactors. The results indicated that Cd removal efficiency of Co-sys (32.09%) was significantly higher than that of Att-sys (23.24%) and Htt-sys (0.74%). By analyzing the soil microbial community in different bioleaching systems, we found that the addition of heterotrophic isolates significantly promoted the growth of some heavy metal resistant inhabitants (Massilia, Alicyclobacillus, Micromonospora, etc.), and Co-sys had a minor effect on the growth of soil indigenous microbes. In Co-sys, the content of the four Cd fractions all decreased compared with other leaching systems. The analysis of soil physicochemical parameters during the leaching process showed that pH and ORP (oxidation reduction potential) were not the only determinants for Cd removal efficiency in Co-sys, synergistic metabolic activities of autotrophic and heterotrophic strains may be other determinants. This study demonstrated that cooperative bioremediation may prove to be a safe and efficient technique for field application in heavy metal soil pollution.

Bioremediation can be a promising and effective remediation technology for treating Cd contaminated soils. Cooperative bioremediation using heterotrophic and autotrophic mixtures proved to be an efficient, short-term bioremediation strategy for heavy metal contaminated soil.     

How to verify patient identity and blood product compatibility using an electronic bedside transfusion system

Transfusion of an incorrect blood component is an important avoidable serious hazard of transfusion resulting from process errors. Our group and others have taken advantage of new technology and developed electronic transfusion systems for safe transfusion practice in a previous studies. They allow the clinical staff to correctly identify the patient and the blood product at the bedside, ensuring the right blood product is given to the right patient. This video is to demonstrate the process and not to promote any specific product. It is a follow up our previous video clip on electronic remote blood issue in a previous study. The process for correct patient identification originates from the wristband, which contains the patient identification details in a 2D barcode and is printed from the electronic patient record system. These details are associated with the blood sample through using a portable printer to produce a label for the sample tube. The patient details are scanned into the blood bank laboratory information system (LIS) and are then printed on a compatibility label by the LIS, which also contains a 2-dimensional barcode, and is then attached to the blood product. Following an initial visual check of these details by the clinical staff, the electronic bedside system requires that both the patient wristband barcode and the blood product compatibility barcode are scanned. This will electronically verify at the patient's bedside that the right unit is to be given to the right patient. This is the final step in ensuring end-to-end electronic control and safe transfusion practice.     

Immunoblotting and ELISA analysis of HSV-1 and HSV-2-specified polypeptides by using an immunoblocking method

Herpes Simplex Virus (HSV) specified polypeptide antigens were analyzed by immunoblotting and enzyme-linked immunosorbent assay (ELISA) methods. In general, the virus specified proteins showed marked cross-reactivity. However, the HSV-1 specified glycoprotein C could be detected by HSV-1 infected rabbit antiserum only. Two low molecular weight polypeptides showed considerable reactivity with HSV-2 induced immune sera as revealed by an immunoblocking modification of the immunoblotting method. These proteins may prove useful in the serological diagnosis of HSV Type 1 and Type 2 infections.     

Mapping the moisture content of coastal sediments using ASTER data for spectroscopic and mineralogical analyses: a case study in South Korea

Mineralogical characteristics of coastal sediments and their spectral characteristics related to moisture content were analysed for South Korea in this study, and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) short-wave infrared (SWIR) remote sensing approaches for moisture content mapping based on conventional SAM module were proposed in this study. The mineral composition included the major minerals of quartz, alkali feldspar, plagioclase and calcite and the accessary minerals of mica and clay. The absorption features of coastal sediments studied occurred at wavelengths of 1.900 μm for clay minerals and water, 2.200 μm for clay minerals and 2.350 μm for micas and calcite. The spectral signature changed with increased moisture content as the absorption feature at 2.200 μm and 2.350 μm faded out. The fading absorption features shifted the resampled laboratory spectra in a spectral vector space and enabled the use of a SAM module for the ASTER SWIR data. The SAM method effectively distinguished not only the absolute moisture content distribution using the reference spectra but also the relative moisture content distribution without the actual reference spectra for coastal sediments. Given that mineral composition and absorption feature behaviours with regard to the moisture content of soil samples are similar to coastal sediments, this method may be applicable for soil moisture mapping.     

Towards an optimal model for community-based diabetes care: design and baseline data from the Mayo Health System Diabetes Translation Project

The objective of the Mayo Health System Diabetes Translation Project is to assess the impact of three different models of care on the overall quality of diabetes care in the community. The unit of study is the primary care practice with a different model of care implemented at each of three sites. The design incorporates a comparison of a diabetes guideline implementation team initiative (Practice model A), a guideline initiative combined with clinical use of a Diabetes Electronic Management System (DEMS) by primary care providers (Practice model B) and a guideline initiative combined with DEMS utilization combined with electronic review of DEMS patient encounters by an endocrinologist (Practice model C). Administrative data sets were used to define the patient population at each practice. Patients were designated as new, attending or non-attending based on their pattern of visits over the preceding 12 months. A random sample of 200 charts from attending patients at each site was audited at baseline for diabetes-related process and outcome measures. This audit will be repeated yearly during the 2 years of the project. Baseline data revealed significant differences across sites in adherence to certain key indicators of the quality of diabetes care including: frequency of documentation of eye examinations (19, 39 and 37% for sites A, B and C, respectively), haemoglobin A1c monitoring (64, 89 and 77%) and microalbumin monitoring (3, 15 and 6%). The interventions being assessed in this study include traditional (diabetes education; guideline implementation) and modern (DEMS; telemedicine specialist review) methods for improving the quality of diabetes care. In spite of variation in baseline quality indicators, the setting and design should lead to broad applicability of the results and help determine an optimal model of diabetes care in the community.     

Burn wound itch control using H1 and H2 antagonists

This study investigated the use of a combination of H1 and H2 antagonists and topical medications to control burn wound itch. Graeco-Latin square assignment provided an oral combination of 1) cetirizine and cimetidine or 2) diphenhydramine and placebo in four divided doses. The study protocol lasted 16 days divided into 4-day intervals, scoring itch before the initial dose of medication and at 1-hour, 6-hour, and 12-hour intervals after the first medication. A significant difference between mean itch scores across the four times was observed (Wilks' Lambda F = 26.52, df = 3, P <.0005). A three-way nested repeated measures interaction effect (Wilks' Lambda F = 9.85, df = 9, P <.0005) was observed representing a significantly different pattern on days 1 to 4 of the study compared with the remaining days. Controlling for the effect of topical medications, the cetirizine/cimetidine combination demonstrated a dramatic improvement at 1 and 6 hours, and a moderate improvement at 12 hours after initial medication for the day when compared with the diphenhydramine/placebo combination.     

Comparison of grass fuel moisture contents predicted using the McArthur Mark V Grassland Fire Danger Meter and an equation derived from the meter

The moisture content of fully cured grass fuel predicted by the original slide rule version of the McArthur Mark V Grassland Fire Danger Meter may differ by up to 3% in oven dry weight from that predicted for equivalent weather conditions by a commonly used equation derived from the meter. The difference between predicted values from the original meter and the equation is greatest at lower air temperatures (≤ 20°C) and when relative humidity is ≥ 40%. This discrepancy is unlikely to result in substantial differences in calculated fire danger indices, but could affect the results of studies attempting to correlate observed fuel moisture contents with predictions from either the original meter or the equation.     

Analysis and improvement of non-contact SpO2 extraction using an RGB webcam

Peripheral oxygen saturation (SpO2), a vital physiological sign employed in clinical care, is commonly obtained by using a contact pulse oximeter. With the rapid popularization of ordinary red-green-blue (RGB) webcams embedded in devices such as smartphones or laptops, there are broad application prospects for exploring techniques for non-contact SpO2 extraction using RGB webcams. However, many issues remain to be solved in the traditional webcam-based SpO2 extraction methods, such as the inherent low signal-to-noise ratio (SNR) of alternating current (AC) components of RGB signals and the potential defects in using RGB signals combination for SpO2 extraction. In this study, we conducted an in-depth examination of the existing research on webcam-based SpO2 extraction techniques, analyzed the practical problems in using them, and explored new ideas to solve the problems. Rather than roughly using the standard deviations (SD) of AC components for calculations, we performed blind source separation for AC components, and then used the energy coefficients retained in the mixed matrix to replace the variables required in the algorithm. Moreover, steady data was selected to compensate for the potential defects in using RGB signals combination. Through these efforts, the anti-noise capability of the algorithm was significantly enhanced, and the related defects were compensated for. The experimental results indicated that the proposed method produced reliable SpO2 estimation that could potentially—with further research—be used in real applications.     

Activity of lactate dehydrogenase isoenzymes LD1 and LD2 in serum as determined by using an inhibitor of the M-subunit

To measure activities of lactate dehydrogenase (EC 1.1.1.27) isoenzymes LD1 and LD2 in serum, we developed a method involving 1,6-hexanediol as specific inhibitor of the M-subunit. Addition of hexanediol, 0.6 mol/L, to five LD isoenzyme fractions purified from human liver and heart homogenates resulted in complete loss of activities of LD4 and LD5, and partial loss of LD2 and LD3. The activity of LD1, which is composed of the H-subunit only, was not affected. In studying what conditions would allow only the activities of LD1 or LD1 + LD2 to be expressed in serum, we found that the respective activities could be determined by treatment with hexanediol, 0.75 mol/L and 0.55 mol/L, respectively. Results of binding experiments and analytical-recovery tests supported the effectiveness of analyses with this inhibitor in determination of LD1 and LD1 + LD2 activities in serum. Results by this proposed inhibition method correlated well with those by the conventional electrophoretic method for determination of LD1 activity, but LD1 + LD2 activities by the inhibition method were a little less than those by the electrophoretic method, requiring some correction.     

Long-term observation of global black carbon,organic carbon and smoke using CALIPSO and MERRA-2 data

Black carbon (BC), organic carbon (OC) and smoke are some of the aerosols that are emitted during combustion reactions. These air pollutants impact human health and the environment negatively, hence it is important to study their sources and distributions. This work concentrates on three global regions; central South America (CSA), central Africa (CA) and east Asia (EA). The study reveals that biomass burning is responsible for the major emissions of BC, OC and smoke aerosols in the CSA and CA regions during the JJA and SON seasons. The EA region is dominated by BC and smoke aerosols emanating from industrial activities during all seasons. However, a high OC aerosol optical depth is only observed in the MAM season indicating biomass burning during this period. High altitude smoke aerosols up to 10 km are observed in CSA and CA regions in the DJF season. The CSA and CA regions further shows the highest planetary boundary layer height at 1400 m in the JJA and SON seasons.