scholarly journals Solidago sempervirens (seaside goldenrod).

Author(s):  
Julissa Rojas-Sandoval

Abstract Solidago sempervirens is a herb native to North America that has been introduced as an ornamental and to combat soil erosion and stabilize dunes. This species is highly tolerant of both saline soils and salt spray and can be found growing in coastal thickets, salt marshes, sand dunes and the banks of estuaries and lakes, but also in grasslands, disturbed sites, forest edges and along roadsides. This species is adapted to grow in a wide range of climates (from tropical to a humid continental and temperate oceanic climates) and produces large amount of wind-dispersed seeds, which are features that may facilitate its spread into new habitats. S. sempervirens also produces allelochemicals that suppress the establishment and growth of other plant species. Currently, it is listed as invasive in the USA, Japan, the Dominican Republic, the Azores and Australia.

2020 ◽  
Author(s):  
Julissa Rojas-Sandoval

Abstract As many other species within the genus Emilia, E. coccinea is herb that behaves as an environmental and agricultural weed. This fast-growing herb has the potential to rapidly colonize disturbed areas, waste grounds, gardens, forest edges, pastures, active and abandoned cultivated lands, roadsides, dry thickets and riverbanks. This species is adapted to grow in a wide range of environmental conditions and has wind-dispersed seeds, which are features that may facilitate its spread into new habitats. It is listed as invasive in Hawaii, Dominican Republic and New Caledonia.


Author(s):  
Munazza Fatima ◽  
Kara J. O’Keefe ◽  
Wenjia Wei ◽  
Sana Arshad ◽  
Oliver Gruebner

The outbreak of SARS-CoV-2 in Wuhan, China in late December 2019 became the harbinger of the COVID-19 pandemic. During the pandemic, geospatial techniques, such as modeling and mapping, have helped in disease pattern detection. Here we provide a synthesis of the techniques and associated findings in relation to COVID-19 and its geographic, environmental, and socio-demographic characteristics, following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) methodology for scoping reviews. We searched PubMed for relevant articles and discussed the results separately for three categories: disease mapping, exposure mapping, and spatial epidemiological modeling. The majority of studies were ecological in nature and primarily carried out in China, Brazil, and the USA. The most common spatial methods used were clustering, hotspot analysis, space-time scan statistic, and regression modeling. Researchers used a wide range of spatial and statistical software to apply spatial analysis for the purpose of disease mapping, exposure mapping, and epidemiological modeling. Factors limiting the use of these spatial techniques were the unavailability and bias of COVID-19 data—along with scarcity of fine-scaled demographic, environmental, and socio-economic data—which restrained most of the researchers from exploring causal relationships of potential influencing factors of COVID-19. Our review identified geospatial analysis in COVID-19 research and highlighted current trends and research gaps. Since most of the studies found centered on Asia and the Americas, there is a need for more comparable spatial studies using geographically fine-scaled data in other areas of the world.


2021 ◽  
Vol 9 (3) ◽  
pp. 311
Author(s):  
Ben R. Evans ◽  
Iris Möller ◽  
Tom Spencer

Salt marshes are important coastal environments and provide multiple benefits to society. They are considered to be declining in extent globally, including on the UK east coast. The dynamics and characteristics of interior parts of salt marsh systems are spatially variable and can fundamentally affect biotic distributions and the way in which the landscape delivers ecosystem services. It is therefore important to understand, and be able to predict, how these landscape configurations may evolve over time and where the greatest dynamism will occur. This study estimates morphodynamic changes in salt marsh areas for a regional domain over a multi-decadal timescale. We demonstrate at a landscape scale that relationships exist between the topology and morphology of a salt marsh and changes in its condition over time. We present an inherently scalable satellite-derived measure of change in marsh platform integrity that allows the monitoring of changes in marsh condition. We then demonstrate that easily derived geospatial and morphometric parameters can be used to determine the probability of marsh degradation. We draw comparisons with previous work conducted on the east coast of the USA, finding differences in marsh responses according to their position within the wider coastal system between the two regions, but relatively consistent in relation to the within-marsh situation. We describe the sub-pixel-scale marsh morphometry using a morphological segmentation algorithm applied to 25 cm-resolution maps of vegetated marsh surface. We also find strong relationships between morphometric indices and change in marsh platform integrity which allow for the inference of past dynamism but also suggest that current morphology may be predictive of future change. We thus provide insight into the factors governing marsh degradation that will assist the anticipation of adverse changes to the attributes and functions of these critical coastal environments and inform ongoing ecogeomorphic modelling developments.


2020 ◽  
Vol 75 (7-8) ◽  
pp. 179-182
Author(s):  
Murray B. Isman

AbstractInterest in the discovery and development of plant essential oils for use as bioinsecticides has grown enormously in the past 20 years. However, successful commercialization and utilization of crop protection products based on essential oils has thus far lagged far behind their promise based on this large body of research, most notably because with the exceptions of the USA and Australia, such products receive no special status from regulatory agencies that approve new pesticides for use. Essential oil-based insecticides have now been used in the USA for well over a decade, and more recently have seen use in the European Union (EU), Korea, and about a dozen other countries, with demonstrated efficacy against a wide range of pests and in numerous crop systems. For the most part these products are based on commodity essential oils developed as flavor and fragrance agents for the food and cosmetic industries, as there are formidable logistic, economic, and regulatory challenges to the use of many other essential oils that otherwise possess potentially useful bioactivity against pests. In spite of these limitations, the overall prospects for biopesticides, including those based on essential oils, are encouraging as the demand for sustainably-produced and/or organic food continues to increase worldwide.


1991 ◽  
Vol 69 (7) ◽  
pp. 1593-1599 ◽  
Author(s):  
César S. B. Costa ◽  
Ulrich Seeliger ◽  
César V. Cordazzo

We studied the effect of nutrient status and sand movement on the population biology of Panicum racemosum Spreng. over a 5-year period (1982–1986) on mobile, semifixed and fixed coastal foredune habitats in southern Brazil. The soils were deficient in nitrate, phosphate, and potassium (<0.5, 0.2–1.2, and 3–5 mg/kg, respectively) in all habitats, and a gradient of decreasing availability existed from the mobile to the fixed dunes. Half-lives of leaves were shorter in the fixed dune as compared with the mobile dune. Similarly, half-lives of leaves were shorter in summer than in winter. Experiments using cuttings of P. racemosum tillers showed that as P. racemosum plants grew, so did the deposition of sand on mobile foredunes. The mechanical deposition of sand itself did not stimulate P. racemosum growth. The deposition of saline sand provided a substrate that supported vertical growth of P. racemosum rhizomes and tillers and was a source of adsorbed nutrients. Also, active sand deposition limited the invasion of frontal dunes by other species. Panicum racemosum populations changed from "invader" to "mature" to "regressive" age states over a 5-year period, apparently in response to the spatial patterns of sand deposition and salt spray input. Key words: Panicum, leaf demography, growth vigour, sand dunes, temporal changes.


Author(s):  
Valeriy Demidov ◽  
Oleg Makarov

The monograph summarizes the information over the past 20 years on the currently widely used. The textbook is intended for students of higher educational institutions, studying in the specialty of soil science, as well as specializing in erosion and soil protection. The textbook describes the physical basis and mechanism of erosion processes, based on some sections of hydraulics, hydrology, hydro-and aeromechanics, knowledge of which is necessary to understand the mechanism of water, wind and irrigation soil erosion. The main mathematical models and principles of forecasting the values of soil losses as a result of erosion processes are considered. The textbook will be useful not only for students and postgraduates studying in the specialty of soil science, but also for geographers, ecologists and a wide range of specialists interested in the problems of soil cover conservation and environmental protection.


Author(s):  
I. Labinskaya

Political developments in North Africa and the Middle East that have begun in January 2011 are gaining strength and involve an increasing number of Arab countries. The participants of the Roundtable – experts from IMEMO, Institute of Oriental Studies (RAS), Institute of the USA and Canada (RAS) and Mrs. E. Suponina from “Moscow News” newspaper analyzed a wide range of issues associated with these events. Among them are: 1) the reasons for such a large-scale explosion, 2) the nature of the discussed developments (revolutions, riots?) and who are the subjects of the current “Arab drama”, 3) the role of Islam and political Islamism, 4) the role of external factors.


2021 ◽  
pp. 932-950
Author(s):  
Vladislav Vyacheslavovich Emelyanov

Every few decades, the world order changes due to various geopolitical, economic and other circumstances. For example, as a result of globalization, the world order has undergone significant changes in the last forty years. Globalization has led to the destruction of the postwar world order, as well as to world leadership by the United States and the West. However, in recent decades, as a result of globalization, the U.S. and the West began to cede their leadership to developing countries, so there is now a change in the economic structure of relations in the world system. Today the center of economic growth is in the East, namely in Asia. There are no new superpowers in the world at the moment, but the unipolar world will cease to exist due to the weakening of the U. S. leadership, which will lead to a change in the world order. A new leader, which may replace the U. S., will not have as wide range of advantages as the USA has. Most likely, the essence of the new order will be to unite the largest countries and alliances into blocks, for example, the USA together with the Trans-Pacific Partnership, the EU, etc. The article outlines forecasts of GDP growth rates as well as the global energy outlook; analyzes the LNG market as well as the impact of the pandemic on the global oil and gas market; and lists the characteristics of U. S. geopolitics.


2021 ◽  
pp. 1-34
Author(s):  
Peter Renner ◽  
Swarn Jha ◽  
Yan Chen ◽  
Tariq Chagouri ◽  
Serge Kazadi ◽  
...  

Abstract Effective design of corrosion-resistant coatings is critical for the protection of metals and alloys. Many state-of-the-art corrosion-resistant coatings are unable to satisfy the challenges in extreme environments for tribological applications, such as elevated or cryogenic temperatures, high mechanical loads and impacts, severe wear, chemical attack, or a combination of these. The nature of challenging conditions demands that coatings have high corrosion and wear resistance, sustained friction control, and maintain surface integrity. In this research, multi-performance metal-ceramic composite coatings were developed for applications in harsh environments. These coatings were developed with an easy to fabricate, low-cost, and safe procedure. The coating consisted of boron nitride, graphite, silicon carbide, and transition metals such as chromium or nickel using epoxy as vehicle and bonding agent. Salt spray corrosion tests showed that 1010 carbon steel (1/4 hard temper) substrates lost 20-100× more mass than the coatings. The potentiodynamic polarization study showed better performance of the coatings by seven orders of magnitude in terms of corrosion relative to the substrate. Additionally, the corrosion rates of the coatings with Ni as an additive were five orders of magnitude lower than reported. The coefficient of friction of coatings was as low as 0.1, five to six times lower than that of epoxy and lower than a wide range of epoxy resin-based coatings found in literature. Coatings developed here exhibited potential in applications in challenging environments for tribological applications.


BMJ Open ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. e039978 ◽  
Author(s):  
Hemalkumar B Mehta ◽  
Stephan Ehrhardt ◽  
Thomas J Moore ◽  
Jodi B Segal ◽  
G Caleb Alexander

ObjectivesThe coronavirus disease 2019 (COVID-19) pandemic has prompted many initiatives to identify safe and efficacious treatments, yet little is known regarding where early efforts have focused. We aimed to characterise registered clinical trials assessing drugs or plasma treatments for COVID-19.Design, setting and participantsCross-sectional analysis of clinical trials for the treatment of COVID-19 that were registered in the USA or in countries contributing to the WHO’s International Clinical Trials Registry Platform. Relevant trial entries of drugs or plasma were downloaded on 26 March 2020, deduplicated, verified with reviews of major medical journals and WHO websites and independently analysed by two reviewers.Main outcome(s)Trial intervention, sponsorship, critical design elements and specified outcomesResultsOverall, 201 clinical trials were registered for testing the therapeutic benefits of 92 drugs or plasma, including 64 in monotherapy and 28 different combinations. Only eight (8.7%) products or combinations involved new molecular entities. The other test therapies had a wide range of prior medical uses, including as antivirals, antimalarials, immunosuppressants and oncology treatments. In 152 trials (75.7%), patients were randomised to treatment or comparator, including 55 trials with some form of blinding and 97 open-label studies. The 49 (24.4%) of trials without a randomised design included 29 single armed studies and 20 trials with some comparison group. Most trial designs featured multiple endpoints. Clinical endpoints were identified in 134 (66.7%) of trials and included COVID-19 symptoms, death, recovery, required intensive care and hospital discharge. Clinical scales were being used in 33 (16.4%) trials, most often measures of oxygenation and critical illness. Surrogate endpoints or biomarkers were studied in 88 (42.3%) of trials, primarily assays of viral load. Although the trials were initiated in more than 17 countries or regions, 100 (49.8%) were registered in China and 78 (37.8%) in the USA. Registered trials increased rapidly, with the number of registered trials doubling from 1 March to 26 March 2020.ConclusionsWhile accelerating morbidity and mortality from the COVID-19 pandemic has been paralleled by early and rapid clinical investigation, many trials lack features to optimise their scientific value. Global coordination and increased funding of high-quality research may help to maximise scientific progress in rapidly discovering safe and effective treatments.


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