Reflectance-Based Imaging Spectrometer Error Budget Field Practicum at the Railroad Valley Test Site, Nevada

Calibration and validation determine the quality and integrity of the data provided by sensors and have enormous downstream impacts on the accuracy and reliabilityof the products generated by these sensors. With the imminent launch of the next generation of space borne imaging spectroscopy sensors, the IEEE Geoscience and Remote Sensing Society's (GRSS's) Geoscience Spaceborne Imaging Spectroscopy Technical Committee (GSIS TC) initiated a calibration and validation initiative.This article reports on a recent reflectance-based imaging spectrometer error budget field practicum focused on radiometric calibration of spaceborne imaging spectroscopy sensors. The field exercise, conducted at Railroad Valley in Nevada, provided valuable training for personnel in a variety of Earth observation (EO) areas, from engineers developing future sensors to calibration scientists actively working in the field. Future work in this area will focus on analyzing the data acquired as part of the training to answer numerous scientific questions, e.g., understanding the spatial and spectral homogeneity of the site being measured, identifying the optimal sampling to characterize the site, and optimizating the sampling techniques, including looking into the automation of some measurement protocol aspects. The training exercise was recorded to ensure that the knowledge can be disseminated across the GRSS and wider imaging spectroscopy community

Spectral information system for Australian spectroscopy data

Abstract presented at 2013 Fall Meeting, AGU, San Francisco, California, USA, 9-13 Dec

Intercomparison of Field Methods for Acquiring Ground Reflectance at Railroad Valley Playa for Spectral Calibration of Satellite Data

Ground reflectance was acquired at the Railroad Valley Playa calibration site in Nevada USA using different methods of collection. The data was collected near the time and date of Landsat 8 OLI and Sentinel-2 satellite overpasses so an inter-comparison could be made with the reflectance products to determine which method was more suitable for vicarious calibration. The field spectrometers and reference panels were characterized before the field campaign. A continuous acquisition method was compared to stop and measure collections. Both acquisition methods were collected along an 80 m east-west transect as well as for a series of north-south transects over an 80 x 320 m area, with the stop and measure method being performed at random sampling locations. The measurements were performed using two field spectrometers by three teams of two people to compare the repeatability. The aim of the field campaign was to determine the variability due to the operator and the method of collection

Natural hydrogen seeps or salt lakes: how to make a difference? Grass Patch example, Western Australia

Natural hydrogen exploration is picking up around the world while the geogenic hydrogen system is still a Frontier science. Natural hydrogen seepage can occur in the form of a sub-circular surface feature named by some authors “fairy circles.” Numerous hydrogen seep-alike surface features are visible from the sky in Australia but can be difficult to distinguish from the many salt lakes. In this study, we combined literature review, remote sensing, field and lab measurements (soil gas sampling, X-Ray diffraction, salinity) to uncover a potential hydrogen system and its differences with the salt lakes in the Grass Patch area in Western Australia. The local geology shows a good potential to generate hydrogen. Study of the surface geology and Digital Elevation Model showed that salt lakes are static old features influenced by the soil composition and long-term climatic trend whereas potential hydrogen seeps have recently appeared. This study soil-gas sampling method includes a monitoring procedure compatible with time series measurements via a portable gas analyser, getting rid of artificially produced hydrogen. Low hydrogen values (<30 ppm) have been measured. Those measurements are lower than measurements published along potential hydrogen seeps in Australia. Vegetation indexes are also less constructed than explored fairy circles in Namibia. Salinity and mineralogical results did not indicate any trend with the hydrogen but are coherent with what is found in salt lakes. A microbial system could be the source of the hydrogen but would also be linked to the soil behaviour, climatic parameters, and agricultural practices. This study underlines the need to monitor surface features over few weeks to better understand the evolution of the gas mix seeping above a structure and determine if the periodicity and variability of the leakage can be correlated with bacterial activity or a geogenic hydrogen source

Enhancing plant nutrient availability in composted paddy husk using Bacillus spp. isolated from termite (Coptotermes curvignathus) gut

Paddy husk (PH) is a waste item generated from rice production that can be used as an organic fertilizer through composting. High lignin content is an issue with PH composting as it impedes the production of high-quality organic fertilizer. Improvements to the composting process can enhance the agronomic properties of compost produced from PH. The objectives of this study were to: (i) determine the ability of Bacillus spp. in enhancing the decomposition of PH and (ii) determine the ability of Bacillus spp. in increasing the macronutrient content of composted PH. Different ligninolytic active Bacillus spp. from termite gut (either singly or a cocktail) were added to 7 of 9 compost boxes containing PH compost mixtures and were allowed to decompose for a period of 60 days. Each treatment was represented by 3 samples, and the compost boxes were arranged in a completely randomized design (CRD) with 3 replications. Results showed that the addition of Bacillus spp. promoted the production of matured compost within 60 days with significantly higher amounts of phosphorus, potassium, calcium, and magnesium. Germination index (GI) of all composted PH added with Bacillus spp. ranged from 82.51 to 95.83%, suggesting that composted PH has lower phytotoxicity than compost without Bacillus spp. isolate. In general, addition of Bacillus spp. to PH waste promoted the production of PH composts with improved macronutrient availability and lower phytotoxicity levels

Incidence and outcomes of delayed presentation and surgery in peritoneal surface malignancies

BackgroundPeritoneal surface malignancies (PSM) present insidiously and often pose diagnostic challenges. There is a paucity of literature quantifying the frequency and extent of therapeutic delays in PSM and its impact on oncological outcomes.MethodsA review of a prospectively maintained registry of PSM patients undergoing Cytoreductive Surgery and Hyperthermic Intra-peritoneal Chemotherapy (CRS-HIPEC) was conducted. Causes for treatment delays were identified. We evaluate the impact of delayed presentation and treatment delays on oncological outcomes using Cox proportional hazards models.Results319 patients underwent CRS-HIPEC over a 6-years duration. 58 patients were eventually included in this study. Mean duration between symptom onset and CRS-HIPEC was 186.0 ± 37.1 days (range 18-1494 days) and mean duration of between patient-reported symptom onset and initial presentation was 56.7 ± 16.8 days. Delayed presentation (> 60 days between symptom onset and presentation) was seen in 20.7% (n=12) of patients and 50.0% (n=29) experienced a significant treatment delay of > 90 days between 1st presentation and CRS-HIPEC. Common causes for treatment delays were healthcare provider-related i.e. delayed or inappropriate referrals (43.1%) and delayed presentation to care (31.0%). Delayed presentation was a significantly associated with poorer disease free survival (DFS) (HR 4.67, 95% CI 1.11-19.69, p=0.036).ConclusionDelayed presentation and treatment delays are common and may have an impact on oncological outcomes. There is an urgent need to improve patient education and streamline healthcare delivery processes in the management of PSM

Causal mechanisms and balancing selection inferred from genetic associations with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is the most common reproductive disorder in women, yet there is little consensus regarding its aetiology. Here we perform a genome-wide association study of PCOS in up to 5,184 self-reported cases of White European ancestry and 82,759 controls, with follow-up in a further ∼2,000 clinically validated cases and ∼100,000 controls. We identify six signals for PCOS at genome-wide statistical significance (P<5 × 10(-8)), in/near genes ERBB4/HER4, YAP1, THADA, FSHB, RAD50 and KRR1. Variants in/near three of the four epidermal growth factor receptor genes (ERBB2/HER2, ERBB3/HER3 and ERBB4/HER4) are associated with PCOS at or near genome-wide significance. Mendelian randomization analyses indicate causal roles in PCOS aetiology for higher BMI (P=2.5 × 10(-9)), higher insulin resistance (P=6 × 10(-4)) and lower serum sex hormone binding globulin concentrations (P=5 × 10(-4)). Furthermore, genetic susceptibility to later menopause is associated with higher PCOS risk (P=1.6 × 10(-8)) and PCOS-susceptibility alleles are associated with higher serum anti-Müllerian hormone concentrations in girls (P=8.9 × 10(-5)). This large-scale study implicates an aetiological role of the epidermal growth factor receptors, infers causal mechanisms relevant to clinical management and prevention, and suggests balancing selection mechanisms involved in PCOS risk.This work was supported by the Medical Research Council [U106179472; MC_U106179472; U106179471; MC_U106179471] and the National Human Genome Research Institute of the National Institutes of Health (grant number R44HG006981 to 23andMe). The UK Medical Research Council and Wellcome Trust (092731), together with the University of Bristol, provide core support for the ALSPAC study. AMH assays in ALSPAC were funded with a grant from the US National Institute of Health (R01 DK077659). DAL works in a unit that receives funding from the University of Bristol and the UK Medical Research Council (MC_UU_12013/5).This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ncomms946

Acute decompensated heart failure in a non cardiology tertiary referral centre, Sarawak General Hospital (SGH‑HF)

Abstract Background: Data on clinical characteristics of acute decompensated heart failure (ADHF) in Malaysia especially in East Malaysia is lacking. Methods: This is a prospective observational study in Sarawak General Hospital, Medical Department, from October 2017 to September 2018. Patients with primary admission diagnosis of ADHF were recruited and followed up for 90 days. Data on patient’s characteristics, precipitating factors, medications and short-term clinical outcomes were recorded. Results: Majority of the patients were classified in lower socioeconomic group and the mean age was 59 years old. Hypertension, diabetes mellitus and dyslipidaemia were the common underlying comorbidities. Heart failure with ischemic aetiology was the commonest ADHF admission precipitating factor. 48.6% of patients were having preserved ejection fraction HF and the median NT-ProBNP level was 4230 pg/mL. Prescription rate of the evidencebased heart failure medication was low. The in-patient mortality and the average length of hospital stay were 7.5% and 5 days respectively. 43% of patients required either ICU care or advanced cardiopulmonary support. The 30-day, 90-day mortality and readmission rate were 13.1%, 11.2%, 16.8% and 14% respectively. Conclusion: Comparing with the HF data from West and Asia Pacific, the short-term mortality and readmission rate were high among the ADHF patients in our study cohort. Maladaptation to evidence-based HF prescription and the higher prevalence of cardiovascular risk factors in younger patients were among the possible issues to be addressed to improve the HF outcome in regions with similar socioeconomic background. Keywords: Acute decompensated heart failure, Epidemiology, Sarawak, Southeast Asia, Malaysi

The Ginninderra CH4 and CO2 release experiment: An evaluation of gas detection and quantification techniques

A methane (CH4) and carbon dioxide (CO2) release experiment was held from April to June 2015 at the Ginninderra Controlled Release Facility in Canberra, Australia. The experiment provided an opportunity to compare different emission quantification techniques against a simulated CH4 and CO2 point source release, where the actual release rates were unknown to the participants. Eight quantification techniques were assessed: three tracer ratio techniques (two mobile); backwards Lagrangian stochastic modelling; forwards Lagrangian stochastic modelling; Lagrangian stochastic (LS) footprint modelling; atmospheric tomography using point and using integrated line sensors. The majority of CH4 estimates were within 20% of the actual CH4 release rate (5.8 g/min), with the tracer ratio technique providing the closest estimate to both the CH4 and CO2 release rates (100 g/min). Once the release rate was known, the majority of revised estimates were within 10% of the actual release rate. The study illustrates the power of measuring the emission rate using multiple simultaneous methods and obtaining an ensemble median or mean. An ensemble approach to estimating the CH4 emission rate proved successful with the ensemble median estimate within 16% for the actual release rate for the blind release experiment and within 2% once the release rate was known. The release also provided an opportunity to assess the effectiveness of stationary and mobile ground and aerial CH4 detection technologies. Sensor detection limits and sampling rates were found to be significant limitations for CH4 and CO2 detection. A hyperspectral imager\u27s capacity to image the CH4 release from 100 m, and a Boreal CH4 laser sensor\u27s ability to track moving targets suggest the future possibility to map gas plumes using a single laser and mobile aerial reflector

Clinical Outcome Predictor using Killip Scoring in Acute Decompensated Heart Failure (ADHF): A Non-Cardiac Centre Pilot Experience

Background: Physicians in tertiary centers face a constant challenge in selecting patient with ADHF to be admitted from district healthcare centre, especially with limited resources. Appropriate risk stratification of patients with ADHF would improve the efficiency of our healthcare delivery system. Objective: We aim to find potential relationship between Killip clinical scoring with clinical outcome of ADHF, including in-patient mortality and requirement of advanced cardiorespiratory support. Methods: 35 consecutive cases with a discharge diagnosis of ADHF and admission creatinine clearance of more than 30 were randomly reviewed. Cases were analyzed retrospectively for their Killip score, in-patient mortality, requirement of advance cardiorespiratory care or ICU admission. Results: There were 21 male patients (60%) and 14 female patients. Mean age was 61±19 years old. Mean duration of ward-stay was 6±4 days. Comorbidities were 14 (40%) with history of coronary artery diseases and 17 (49%) with diabetes mellitus. 15 patients (43%) were on at least a single type of guideline directed medication for heart failure. The cohort was almost evenly distributed between those with a Killip score of 2 and above 2. A Killip score of 3 and above was found to have good positive predictive value (87%) for advanced cardio-respiratory care and negative predictive value of 78%. No in-patient death was observed for the group with Killip 2 while 5 deaths were recorded in the group scoring more than 2. A Killip score of 3 had excellent (100%) negative predictive value for in-patient mortality but poor positive predictive value (33%). Significant relationship (p<0.001) was observed for Killip scoring on both outcomes. Conclusion: Killip scoring may be useful for on-call physician to decide the need on tertiary care among patient with ADHF and mortality outcome. However, more prospective studies and patients should be recruited to validate the study