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This study presents an automated methodology to generate training data for surface water mapping from a single Sentinel-2 granule at 10 m (4 band, VIS/NIR) or 20 m (9 band, VIS/NIR/SWIR) resolution without the need for ancillary training data layers. The 20 m method incorporates an ensemble of three spectral indexes with optimal band thresholds, whereas the 10 m method achieves similar results using fewer bands and a single spectral index. A spectrally balanced and randomly generated set of training data based on the index values and optimal thresholds is used to fit machine learning classifiers. Statistical validation compares the 20 m ensemble-only method to the 20 m ensemble method with a random forest classifier. Results show the 20 m ensemble-only method had an overall accuracy of 89.5% (±1.7%), whereas the ensemble method combined with the random forest classifier performed better, with a ~4.8% higher overall accuracy: 20 m method (94.3% (±1.3%)) with optimal spectral index and SWIR thresholds of −0.03 and 800, respectively, and 10 m method (93.4% (±1.5%)) with optimal spectral index and NIR thresholds of −0.01 and 800, respectively. Comparison of other supervised classifiers trained automatically with the framework typically resulted in less than 1% accuracy improvement compared with the random forest, suggesting that training data quality is more important than classifier type. This straightforward framework enables accurate surface water classification across diverse geographies, making it ideal for development into a decision support tool for water resource managers.

Monitoring the impacts of ecosystem restoration strategies requires both short-term and long-term land surface monitoring. The combined use of unmanned aerial systems (UAS) and satellite imagery enable effective landscape and natural resource management. However, processing, analyzing, and creating derivative imagery products can be time consuming, manually intensive, and cost prohibitive. In order to provide fast, accurate, and standardized UAS and satellite imagery processing, we have developed a suite of easy-to-use tools integrated into the graphical user interface (GUI) of ArcMap and ArcGIS Pro as well as open-source solutions using NodeOpenDroneMap. We built the Monitoring Ecological Restoration with Imagery Tools (MERIT) using Python and leveraging third-party libraries and open-source software capabilities typically unavailable within ArcGIS. MERIT will save US Army Corps of Engineers (USACE) districts significant time in data acquisition, processing, and analysis by allowing a user to move from image acquisition and preprocessing to a final output for decision-making with one application. Although we designed MERIT for use in wetlands research, many tools have regional or global relevancy for a variety of environmental monitoring initiatives.

Feature extraction algorithms are routinely leveraged to extract building footprints and road networks into vector format. When used in conjunction with high resolution remotely sensed imagery, machine learning enables the automation of such feature extraction workflows. However, many of the feature extraction algorithms currently available have not been thoroughly evaluated in a scientific manner within complex terrain such as the cities of developing countries. This report details the performance of three automated feature extraction (AFE) datasets: Ecopia, Tier 1, and Tier 2, at extracting building footprints and roads from high resolution satellite imagery as compared to manual digitization of the same areas. To avoid environmental bias, this assessment was done in two different regions of the world: Maracay, Venezuela and Niamey, Niger. High, medium, and low urban density sites are compared between regions. We quantify the accuracy of the data and time needed to correct the three AFE datasets against hand digitized reference data across ninety tiles in each city, selected by stratified random sampling. Within each tile, the reference data was compared against the three AFE datasets, both before and after analyst editing, using the accuracy assessment metrics of Intersection over Union and F1 Score for buildings and roads, as well as Average Path Length Similarity (APLS) to measure road network connectivity. It was found that of the three AFE tested, the Ecopia data most frequently outperformed the other AFE in accuracy and reduced the time needed for editing.

Background: Post-liver-transplant biliary anastomotic strictures (ASs) are currently managed with repeated endoscopic retrograde cholangiopancreatographies (ERCPs) inserting multiple plastic stents. Fully covered self-expanding metal stents (FCSEMSs) are being increasingly reported in the management of this condition, however no prospective randomized trials have been performed to date. Aim: The aim of this study was to determine whether FCSEMSs decrease overall numbers of ERCPs needed to achieve stricture resolution and to establish the safety, efficacy and cost-effectiveness in this setting. Methods: Two tertiary referral centres performed this open-label prospective randomized trial. A total of 32 patients consented and subsequently 20 were randomized with 10 in the FCSEMS arm and 10 in the plastic arm. The FCSEMS arm had the stent in situ for 12 weeks with the plastic stent arm undergoing 3-monthly multiple plastic stenting with or without dilatation over a year. Results: The median number of ERCPs performed per patient in the FCSEMS was 2 versus 4.5 ( p = 0.0001) in the plastic stenting arm. Stricture resolution was achieved in all 10 patients with FCSEMSs compared with 8/10 in the plastic arm [ p = not significant (NS)]. Complications occurred in 1/10 patients in the FCSEMS arm versus 5/10 in the plastic arm ( p = 0.051). Days in hospital for complications was 6 in the FCSEMS versus 56 in the plastic arm ( p = 0.11). Cost analysis shows that the FCSEMS arm was more cost effective. No cases of FCSEMS migration were seen. Conclusions: FCSEMSs reduced the number of ERCPs needed to achieve stricture resolution with similar recurrence rates between arms. The FCSEMSs may do so with fewer complications making it cost effective.

Background and study aims: Removal of colonic polyps prevents progression of colonic neoplasia. Miss rates of polyps range from 5 % to 32 %. The effect of colonic contractility on polyp detection has not been studied adequately. Hyoscine butylbromide results in colonic spasmolysis and may improve polyp detection. Patients and methods: Patients undergoing colonoscopy for standard indications were included and randomized to receive either 20 mg hyoscine butylbromide or placebo at cecal intubation. Operators were blind to the intervention. Data on indication, preparation, sedation, colonoscope type, times of insertion/withdrawal, polyps, and failure were recorded. The primary end point was the number of polyps detected per patient. Secondary endpoints were adenoma detection rate and polyp detection rate. Results: A total of 303 patients received hyoscine butylbromide and 298 received placebo. More polyps per patient were identified in the hyoscine group than in the placebo group (0.91 vs. 0.70; P = 0.044). Adenoma detection rate and polyp detection rate were higher in the hyoscine arm but not significantly different (27.1 % vs. 21.8 % [P = 0.13] and 43.6 % vs. 36.6 % [P = 0.08], respectively). After adjusting for confounding variables, the odds of detecting any polyp were 1.56 higher in the hyoscine than the placebo group (95 % confidence interval [CI] 1.09 – 2.21, P = 0.014). The adjusted odds of detecting any adenoma were 1.62 higher in the hyoscine group compared with the placebo group (95 %CI 1.09 – 2.42, P = 0.017). There were no differences in baseline characteristics between the groups. No adverse colonoscopy-related events were recorded. One patient experienced transient tachycardia without sequelae. Conclusions: Hyoscine butylbromide administered at the cecum aids polyp detection. Further studies are required to determine the contribution of colonic spasm to polyp miss rates.

Colonies of Pocillopora damicornis from Kaneohe Bay and colonies of Pocillopora meandrina from a thermal outfall site and a control site at Kahe were exposed to three different temperatures (29, 32 and 33 °C) in outdoor aquaria on running water tables for five days. Samples ( n = 3) were taken from each treatment at 0800, 1200 and 1600 h. ELISAs using catalase antibodies and ferric reducing/antioxidant potential (FRAP) assays were run on the samples to determine how antioxidant levels changed throughout the experiment. Light levels during the experiment were highest in the morning (≈ 1000–1500 μmol quanta m − 2 s − 1 ) and decreased to 25–60 μmol quanta m − 2 s − 1 by 1100 h and remained low until sunset. Antioxidant concentrations were highest in the morning for P. damicornis from Kaneohe and P. meandrina outfall samples. There was no significant change through the day for P. meandrina samples from the control site. The difference in response between the outfall samples and the control samples suggests that P. meandrina has acclimated to elevated temperatures found at the outfall site.

Coral tumors are atypical skeletal forms found on coral reefs worldwide. Here we present an analysis of the microbial communities associated with skeletal tumors on the coral Porites compressa. Microbial growth rates on both healthy and tumorous P. compressa were decoupled from the surrounding water column. Microbial communities associated with tumorous colonies had a significantly faster growth rate than those associated with healthy P. compressa. The microbial community associated with the tumors contained more culturable Vibrio spp. and could utilize more carbon sources than the microbes associated with healthy colonies. Presence of tumors affected the composition and dynamics of the microbial population associated with the entire colony.

Appendectomy has been shown to protect against the development of ulcerative colitis. The objective of this study was to examine the effect of appendectomy on the clinical features and natural history of colitis.A total of 259 consecutive adults patients with ulcerative colitis were studied. Of the patients, 20 had undergone appendectomy (12 before onset of colitis and eight after diagnosis).The frequency of appendectomy was significantly less than in a group of 280 controls, which comprised partners of the patients and a group from the community (OR = 0.25; 95% CI = 0.14-0.44). This was even more significant if only the 12 patients who underwent surgery before the onset of colitis were considered (OR = 0.15; 95% CI = 0.07-0.28). Patients with prior appendectomy developed symptoms of ulcerative colitis for the first time at a significantly later age than those without appendectomy (42.5 +/- 6.5 vs 32.1 +/- 0.8 yr; p0.01) or those who had appendectomy after the onset of colitis (24.6 +/- 3.4 yr; p0.05). Appendectomy did not influence disease extent, need for immunosuppressive treatment with azathioprine or 6-mercaptopurine (as a marker of resistant disease), or the likelihood of colectomy. Five patients in the appendectomy group had clinical evidence of primary sclerosing cholangitis (25%). This was more common than in those without appendectomy (8%; OR = 4.09; 95% CI = 1.04-13.60).These results indicate that although appendectomy may delay onset of colitis, it does not influence its course. However, it is associated with the development of primary sclerosing cholangitis. Appendectomy is unlikely to be of benefit in established ulcerative colitis.

Web-based simulation, a subject of increasing interest to both simulation researchers and practitioners, has the potential to significantly influence the application and availability of simulation as a problem-solving technique. Web technologies also portend cost-effective distributed modeling and simulation. These applications will require solutions to the systems interoperability problem similar to the DoD High Level Architecture (HLA). The suitability of the HLA to serve 'mainstream' simulation is examined.Approaches for incorporating discrete event simulation conceptual frameworks within the HLA are described and ongoing research in this area noted. Issues raised include a discussion of the appropriate roles for a simulation-support language and a simulation-support architecture.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An investigation is underway regarding technologies to support the design, development and use of distributed, web-based simulations. As part of this investigation the Simjava simulation-support package has been extended to utilize the Remote Method Invocation facilities of the Java Development Kit (JDK) 1.1. Current efforts with Simjava are described and future research directions are outlined.

The Aggregate Level Simulation Protocol (ALSP) interface technique is now entering its second year of practical application. ALSP is designed to permit multiple, pre-existing combat simulations to interact with each other over local and wide area networks. Army, Navy, and Air Force, simulations have been linked, using ALSP, to form a confederation of models capable of supporting major military exercises. This exercise experience has reinforced many of the initial ALSP design decisions, called others into question, and revealed some new requirements. The basic ALSP system software services, practical features derived of operational experience, and the current research efforts are described.

AIM: To study the significance of cap-fitted colonoscopy in improving cecal intubation time and polyp detection rate. METHODS: This study was a prospective randomized controlled trial conducted from March 2008 to February 2009 in a tertiary referral hospital at Sydney. The primary end point was cecal intubation time and the secondary endpoint was polyp detection rate. Consecutive cases of total colonoscopy over a 1-year period were recruited. Randomization into either standard colonoscopy (SC) or cap-assisted colonoscopy (CAC) was performed after consent was obtained. For cases randomized to CAC, one of the three sizes of cap was used: D-201-15004 (with a diameter of 15.3 mm), D-201-14304 (14.6 mm) and D-201-12704 (13.0 mm). All of these caps were produced by Olympus Medical Systems, Japan. Independent predictors for faster cecal time and better polyp detection rate were also determined from this study. RESULTS: There were 200 cases in each group. There was no significant difference in terms of demographic characteristics between the two groups. CAC, when compared to the SC group, had no significant difference in terms of cecal intubation rate (96.0% vs 97.0%, P = 0.40) and time (9.94 ± 7.05 min vs 10.34 ± 6.82 min, P = 0.21), or polyp detection rate (32.8% vs 31.3%, P = 0.75). On the subgroup analysis, there was no significant difference in terms of cecal intubation time by trainees (88.1% vs 84.8%, P = 0.40), ileal intubation rate (82.5% vs 79.0%, P = 0.38) or total colonoscopy time (23.24 ± 13.95 min vs 22.56 ± 9.94 min, P = 0.88). On multivariate analysis, the independent determinants of faster cecal time were consultant-performed procedures (P < 0.001), male patients (P < 0.001), non-usage of hyoscine (P < 0.001) and better bowel preparation (P = 0.01). The determinants of better polyp detection rate were older age (P < 0.001), no history of previous abdominal surgery (P = 0.04), patients not having esophagogastroduodenoscopy in the same setting (P = 0.003), trainee-performed procedures (P = 0.01), usage of hyoscine (P = 0.01) and procedures performed for polyp follow-up (P = 0.01). The limitations of the study were that it was a single-center experience, no blinding was possible, and there were a large number of endoscopists. CONCLUSION: CAC did not significantly different from SC in term of cecal intubation time and polyp detection rate.