A method for creating a burn severity atlas: an example from Alberta, Canada

2020 ◽  
Vol 29 (11) ◽  
pp. 995
Author(s):  
Ellen Whitman ◽  
Marc-André Parisien ◽  
Lisa M. Holsinger ◽  
Jane Park ◽  
Sean A. Parks

Wildland fires are globally widespread, constituting the primary forest disturbance in many ecosystems. Burn severity (fire-induced change to vegetation and soils) has short-term impacts on erosion and post-fire environments, and persistent effects on forest regeneration, making burn severity data important for managers and scientists. Analysts can create atlases of historical and recent burn severity, represented by changes in surface reflectance following fire, using satellite imagery and fire perimeters. Burn severity atlas production has been limited by diverse constraints outside the US. We demonstrate the development and validation of a burn severity atlas using the Google Earth Engine platform and image catalogue. We automated mapping of three burn severity metrics using mean compositing (averaging reflectance values) of pixels for all large (≥200ha) fires in Alberta, Canada. We share the resulting atlas and code. We compared burn severity datasets produced using mean compositing with data from paired images (one pre- and post-fire image). There was no meaningful difference in model correspondence to field data between the two approaches, but mean compositing saved time and increased the area mapped. This approach could be applied and tested worldwide, and is ideal for regions with small staffs and budgets, and areas with frequent cloud.

2019 ◽  
Vol 15 (5) ◽  
pp. 591-598 ◽  
Author(s):  
Haitham Alrabiah ◽  
Ahmed Bakheit ◽  
Sabray Attia ◽  
Gamal A.E. Mostafa

Background: Conivaptan inhibits two of vasopressin receptor (vasopressin receptor V1a and V2). Conivaptan is used for the treatment of hyponatremia, and in some instances, for the treatment of the heart failure. Methods: The present study aimed to develop a simple, sensitive, and accurate HPLC with ultraviolet detection for the assay of conivaptan (CON) in mouse plasma using bisoprolol as internal standard (IS). A precipitation procedure was used to extract CON and the IS from the mouse plasma. CON was chromatographically separated using a C18 analytical column at 25°C. The separation was carried out using a mixture of phosphate buffer (50 mM): acetonitrile (60: 40, v/v, pH 4.5) with a flow rate of 1.0 mL/min and detection was performed at 240 nm. Results: The assay was validated according to the US Food and Drug (FDA) guidelines. The method demonstrated linearity over a concentration range of 150 - 2000 ng/mL (correlation coefficient: r 2 = 0.9985). The mean recovery of CON from the mouse plasma was 101.13%. All validation parameters for CON were within the acceptable range. Conclusion: The investigated method has been shown to be suitable for estimating the CON in plasma samples, and this method is sensitive and highly selective, allowing the estimation of its concentrations up to the nano-scale. The suggested method was successfully used in a pharmacokinetic study of CON in mouse plasma.


2020 ◽  
Vol 12 (11) ◽  
pp. 4563
Author(s):  
Sangpil Ko ◽  
Pasi Lautala ◽  
Kuilin Zhang

Rail car availability and the challenges associated with the seasonal dynamics of log movements have received growing attentions in the Lake Superior region of the US, as a portion of rail car fleet is close to reaching the end of its service life. This paper proposes a data-driven study on the rail car peaking issue to explore the fleet of rail cars dedicated to being used for log movements in the region, and to evaluate how the number of cars affects both the storage need at the sidings and the time the cars are idled. This study is based on the actual log scale data collected from a group of forest companies in cooperation with the Lake State Shippers Association (LSSA). The results of our analysis revealed that moving the current log volumes in the region would require approximately 400–600 dedicated and shared log cars in ideal conditions, depending on the specific month. While the higher fleet size could move the logs as they arrive to the siding, the lower end would nearly eliminate the idling of rail cars and enable stable volumes throughout the year. However, this would require short-term storage and additional handling of logs at the siding, both elements that increase the costs for shippers. Another interesting observation was the fact that the reduction of a single day in the loading/unloading process (2.5 to 1.5 days) would eliminate almost 100 cars (20%) of the fleet without reduction in throughput.


Oecologia ◽  
2015 ◽  
Vol 180 (3) ◽  
pp. 903-916 ◽  
Author(s):  
Nárgila G. Moura ◽  
Alexander C. Lees ◽  
Alexandre Aleixo ◽  
Jos Barlow ◽  
Erika Berenguer ◽  
...  

Author(s):  
Alvaro Moreno-Martinez ◽  
Emma Izquierdo-Verdiguier ◽  
Gustau Camps-Valls ◽  
Marco Moneta ◽  
Jordi Munoz-Mari ◽  
...  

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Abbas Khan ◽  
Muhammad Yar Khan ◽  
Abdul Qayyum Khan ◽  
Majid Jamal Khan ◽  
Zia Ur Rahman

Purpose By testing the weak form of efficient market hypothesis (EMH) this study aims to forecast the short-term stock prices of the US Dow and Jones environmental socially responsible index (SRI) and Shariah compliance index (SCI). Design/methodology/approach This study checks the validity of the weak form of EMH for both SCI and SRI prices by using different parametric and non-parametric tests, i.e. augmented Dickey-Fuller test, Philip-Perron test, runs test and variance ratio test. If the EMH is invalid, the research further forecasts short-term stock prices by applying autoregressive integrated moving average (ARIMA) model using daily price data from 2010 to 2018. Findings The research confirms that a weak form of EMH is not valid in the US SRI and SCI. The historical data can predict short-term future price movements by using technical ARIMA model. Research limitations/implications This study provides better guidance to risk-averse national and international investors to earn higher returns in the US SRI and SCI. This study can be extended to test the EMH of Islamic equity in the Middle East and North Africa region and other top Islamic indexes in the world. Originality/value This study is a new addition to the existing literature of equity investment and price forecasting by comparing and investigating the market efficiency of two interrelated US SRI and SCI.


1992 ◽  
Vol 6 (1) ◽  
pp. 24-29
Author(s):  
Barry Stern

To provide an overview of the US perspective on university–industry cooperation, the author focuses on four areas: (a) the roles of governments, the higher education sector, and industry in continuing technological education; (b) cooperation between higher education and industry in developing technological education; (c) areas in which Europe, Japan, and the USA can fruitfully cooperate in continuing technological education; and (d) major challenges for the short-term future.


Neurology ◽  
2018 ◽  
Vol 91 (19) ◽  
pp. e1778-e1787 ◽  
Author(s):  
Kristen M. Krysko ◽  
Jennifer Graves ◽  
Mary Rensel ◽  
Bianca Weinstock-Guttman ◽  
Gregory Aaen ◽  
...  

ObjectiveTo characterize the use and safety of newer disease-modifying therapies (DMTs) in children with multiple sclerosis (MS) and clinically isolated syndrome (CIS) treated under 18 years of age.MethodsThis is a cohort study including children with MS or CIS followed at 12 outpatient practices participating in the US Network of Pediatric MS Centers. DMT use, including duration, dose, and side effects, was analyzed. Newer DMTs were defined as agents receiving Food and Drug Administration approval or with increased use in adult MS after 2005.ResultsAs of July 2017, 1,019 pediatric patients with MS (n = 748) or CIS (n = 271) were enrolled (65% female, mean onset 13.0 ± 3.9 years, mean follow-up 3.5 ± 3.1 years, median 1.6 visits per year). Of these, 78% (n = 587) with MS and 11% (n = 31) with CIS received DMT before 18 years of age. This consisted of at least one newer DMT in 42%, including dimethyl fumarate (n = 102), natalizumab (n = 101), rituximab (n = 57), fingolimod (n = 37), daclizumab (n = 5), and teriflunomide (n = 3). Among 17%, the initial DMT prescribed was a newer agent (36 dimethyl fumarate, 30 natalizumab, 22 rituximab, 14 fingolimod, 2 teriflunomide). Over the last 10 years, the use of newer agents has increased, particularly in those ≥12 years and to lesser extent in those <12 years. The short-term side effect profiles of newer DMTs did not differ from those reported in adults.ConclusionNewer DMTs are often used in pediatric MS, and have similar short-term safety, tolerability, and side effect profiles as in adults. These findings may help inform pediatric MS management.


2005 ◽  
Vol 5 (2) ◽  
pp. 151-156 ◽  
Author(s):  
Rodolfo Salm ◽  
Euphly Jalles-Filho ◽  
Cynthia Schuck-Paim

In this study we propose a model that represents the importance of large arborescent palms in the dynamics of seasonally-dry Amazonian forests. Specifically, the model is aimed at guiding the investigation of the role of large arborescent palms on forest regeneration and succession. Following disturbance, the high level of luminosity reaching recently formed forest gaps favors the quick proliferation of shade-intolerant lianas that, by casting shade on the crowns of mature forest trees and increasing tree-fall probability, suppress forest succession. Due to their columnar architecture palm trees are, however, not severely affected by vines. As the palms grow, the canopy at the gaps becomes gradually higher and denser, progressively obstructing the passage of light, thus hindering the growth of shade-intolerant lianas and enabling late-successional tree development and forest regeneration. Owing to the long time associated with forest regeneration, the model cannot be tested directly, but aspects of it were examined with field data collected at an Attalea maripa-rich secondary forest patch within a matrix of well-preserved seasonally-dry forest in the Southeastern Amazon. The results indicate that (1) forest disturbance is important for the recruitment of large arborescent palms species, (2) these palms can grow rapidly after an event of disturbance, restoring forest canopy height and density, and (3) secondary forest dominated by palm trees species may be floristically similar to nearby undisturbed forests, supporting the hypothesis that the former has undergone regeneration, as purported in the model.


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