Unexpectedly high among-habitat spider (Araneae) faunal diversity from the Arctic Long-Term Experimental Research (LTER) field station at Toolik Lake, Alaska, United States of America

2013 ◽  
Vol 145 (2) ◽  
pp. 219-226 ◽  
Author(s):  
Derek S. Sikes ◽  
Michael L. Draney ◽  
Brandi Fleshman
Keyword(s):  
United States ◽  
Experimental Research ◽  
United States Of America ◽  
The Arctic ◽  
Estimation Methods ◽  
Field Station ◽  
Species Richness Estimation ◽  
Faunal Diversity ◽  
Toolik Lake

AbstractA comparison is made between a three-year structured-sampling study that compared spider faunas of two tundra habitats and a single-year unstructured-sampling study, both within the Arctic Long-Term Experimental Research (LTER) field station at Toolik Lake, Alaska, United States of America. The three-year study documented 51 species and predicted a total of 60 species for the area. Our one season study documented 39 species, of which 24, or 62%, are not shared by the three-year study, raising the total count for the LTER to 75 species. These findings emphasise limitations of species richness estimation methods and help dispel the perception that Arctic tundras are homogeneous and species poor.

scholarly journals U.S. Arctic policy: the agenda of 2019

2020 ◽  
pp. 25-37
Author(s):  
Andrei Andreevich Kovalev
Keyword(s):  
United States ◽  
Arctic Region ◽  
The United States ◽  
Climatic Changes ◽  
The Arctic ◽  
Arctic Policy ◽  
Defense Cooperation ◽  
Relevant Consideration ◽  
The Arctic Region

This article explores the key stages of the development of U.S. policy with regards to Arctic Region. The goal is set to outline the fundamental interests of the United States in the Arctic, as well as analyze the actions aimed at their achievement. The article examines the main priorities in U.S. Arctic policy, namely the protection and preservation of resources and ecosystem in the Arctic Region, scientific study of climatic changes, peculiarities of economic development of Alaska, and national security interests of the state. The questions of interaction of Arctic states with regards to defense cooperation become increasingly relevant. Consideration of the mid-term and long-term prospects of U.S. Arctic policy allowed the author focusing attention on the news aspects of U.S. government actions. Maritime capabilities of the United States in the Arctic waters are views in the context of modern tendencies. The author attempted to trace the prospects for expansion of U.S. influence in the Arctic Region based on the current agenda of 2019.

Social and cultural policies to confront the Takfiri speech in Iraq after the year 2003

2020 ◽  
pp. 37
Author(s):  
Ahmed Ghaleb Mohi
Keyword(s):  
United States ◽  
Middle East ◽  
United States Of America ◽  
Political System ◽  
The United States ◽  
Cultural Policies ◽  
American Occupation ◽  
East Region ◽  
Middle East Region

The American occupation of Iraq in 2003 represented a detailed event whose repercussions and repercussions affected not only the level of changing the Iraqi political system, but this event had geo-political and strategic long-term dimensions, as the United States of America was able to redraw the paths of the Middle East region again, in line with The strategic dimensions that I planned to achieve.

Composition and concentrations of aerosol precursor gases in the sub-Arctic boreal forest

2021 ◽  
Author(s):  
Tuija Jokinen ◽  
Katrianne Lehtipalo ◽  
Kimmo Neitola ◽  
Nina Sarnela ◽  
Totti Laitinen ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Sulfuric Acid ◽  
Ambient Air ◽  
Particle Formation ◽  
The Arctic ◽  
New Particle Formation ◽  
Aerosol Formation ◽  
Iodic Acid ◽  
Field Station

<p>One way to form aerosol particles is the condensation of oxidized atmospheric trace gases, such as sulfuric acid (SA) into small molecular clusters. After growing to larger particles by condensation of low volatile gases, they can affect the planets climate directly by scattering light and indirectly by acting as cloud condensation nuclei. Observations of low-volatility aerosol precursor gases have been reported around the world but long-term measurement series and Arctic data sets showing seasonal variation are close to non-existent. In here, we present ~7 months of aerosol precursor gas measurements performed with the nitrate based chemical ionization mass spectrometer (CI-APi-TOF). We deployed our measurements ~250 km above the Arctic Circle at the Finnish sub-Arctic field station, SMEAR I in Värriö. We report concentration measurements of the most common new particle formation related compounds; sulfuric acid, methanesulfonic acid (MSA), iodic acid (IA) and highly oxygenated organic compounds, HOMs. At this remote measurement site, surrounded by a strict nature preserve, that gets occasional pollution from a Russian city of Murmansk, SA is originated both from anthropogenic and biological sources and has a clear diurnal cycle but no significant seasonal variation, while MSA as an oxidation product of purely biogenic sources is showing a more distinct seasonal cycle. Iodic acid concentrations are the most stable throughout the measurement period, showing almost identical peak concentrations for spring, summer and autumn. HOMs are abundant during the summer months and due to their high correlation with ambient air temperature, we suggest that most of HOMs are products of monoterpene oxidation. New particle formation events at SMEAR I happen under relatively low temperatures, low relative humidity, high ozone concentration, high SA concentration in the morning and high MSA concentrations in the afternoon. The role of HOMs in aerosol formation will be discussed. All together, these are the first long term measurements of aerosol forming precursor from the sub-arctic region helping us to understand atmospheric chemical processes and aerosol formation in the rapidly changing Arctic.</p><p> </p><p> </p>

scholarly journals China’s Arctic Policy: Challenges to Regional Security (1990s – 2020s)

2021 ◽  
pp. 377-388
Author(s):  
Oleksandr Horobets ◽  
Keyword(s):  
United States ◽  
Large Scale ◽  
Arctic Region ◽  
The United States ◽  
The Arctic ◽  
Regional Security ◽  
The World ◽  
Arctic Policy ◽  
The Arctic Region

The article analyzes the evolution of China's Arctic policy, which has expanded over three decades from individual polar research to observer status in the Arctic Council and the existence of a state Arctic strategy. China and Russia have established mutually beneficial cooperation in the Arctic region in such conditions, when in many areas there are fundamental contradictions between the countries. The West did not have a long-term strategy capable of responding to current security challenges, including in the Arctic. When Russia tried to regain lost positions on the world stage in 2007-2008, China became an increasingly influential player in the world. If before the Arctic had been outside the lines of rivalry for decades, the question of the Far North as an arena of military competition began to take first place. China has become a long-term threat to both the United States and Russia. In previous years, with the help of the China, Moscow had the opportunity to receive the necessary investments and technologies for large-scale Arctic projects. The more Beijing attempts to establish itself as an influential player in the Arctic, the more the threat to other Arctic countries will grow. The Russian Federation has positioned itself as a leader in the region. The country's policy was aimed at strengthening this status through regional control and expansion of the military presence. This led to a response from the United States and NATO countries. In Russia it was assessed as a threat. The question arises as to what the strategy of the United States should be, and whether it will be possible to resist the costly arms race. If not, then the competition will be concentrated in the political and economic spheres. A particular aspect is the rapid militarization of the Arctic region after 2014, primarily due to changes in Russia's military strategy, which extends to the North. This has led to the tensions between the United States and Russia. China has not yet resorted to expand its military power in the Arctic. China's policy of economic and infrastructural influence is opposed to military methods. The effectiveness of Chinese non-military methods of influence is assessed

A Review on Noval Anticoagulants

2017 ◽  
Vol 9 (1) ◽  
Author(s):  
Rakhi Krishna ◽  
Bhama Santhosh Kumar ◽  
Surya Krishnan ◽  
Anila K N ◽  
Lakshmi R.
Keyword(s):  
United States ◽  
Atrial Fibrillation ◽  
United States Of America ◽  
Anticoagulation Therapy ◽  
Preventive Measure ◽  
Pharmacological Properties ◽  
Nonvalvular Atrial Fibrillation ◽  
Vte Prophylaxis ◽  
Dosing Regimens

The long term anticoagulation with warfarin is associated with various bleeding risks which led to the need for newer drugs. With the developments in the anticoagulation therapy the newer agents like dabigatran, rivaroxaba, apixaban and edoxaban have gained popularity with their more predictable pharmacological properties and reduced need for drug monitoring.The United States of America has approved both rivaroxaban and dabigatran to be used in the treatment of VTE (Venous Thrombo Embolism). In Europe and Canada dabigatran is prescribed after elective hip or knee arthroplasty to prevent VTE. For a VTE prophylaxis after an orthopediac surgery and to prevent stroke in AF patient, Rivaroxaban is recommended according to RECORD study. Edoxaban is highly effective in treatment of VTE and acts as a preventive measure of stroke in NVAF (Nonvalvular Atrial Fibrillation). Through this article various pharmacological aspects, dosing regimens, bleeding associated risk will be illustrated.

scholarly journals A century of decoupling size and structure of urban spaces in the United States

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Johannes H. Uhl ◽  
Dylan S. Connor ◽  
Stefan Leyk ◽  
Anna E. Braswell
Keyword(s):  
United States ◽  
United States Of America ◽  
Metropolitan Areas ◽  
The United States ◽  
Present Form ◽  
Urban Spaces ◽  
Development Trajectories ◽  
Similar Development ◽  
Over Time

AbstractMost cities in the United States of America are thought to have followed similar development trajectories to evolve into their present form. However, data on spatial development of cities are limited prior to 1970. Here we leverage a compilation of high-resolution spatial land use and building data to examine the evolving size and form (shape and structure) of US metropolitan areas since the early twentieth century. Our analysis of building patterns over 100 years reveals strong regularities in the development of the size and density of cities and their surroundings, regardless of timing or location of development. At the same time, we find that trajectories regarding shape and structure are harder to codify and more complex. We conclude that these discrepant developments of urban size- and form-related characteristics are driven, in part, by the long-term decoupling of these two sets of attributes over time.

scholarly journals GTE Union Organization A Case Study

2007 ◽  
Vol 3 (3) ◽  
pp. 81-90
Author(s):  
Russell K. Baker
Keyword(s):  
United States ◽  
Collective Bargaining ◽  
United States Of America ◽  
Representation Election ◽  
Final Phase ◽  
Labor Management ◽  
Union Representation ◽  
Term Labor

On November 19, 1993 the following notice was sent to the office of the general manager of GTE Supply Company in Tampa, Florida:Gentlemen:A petition for certification as collective bargaining representative of certain of your employees has been filed with this office, pursuant to the Labor Management Relations Act, as amended. A copy of the petition is enclosed. Should you desire further information before a Board Agent communicates with you, telephone or write the office to which the case is being assigned, referring to the above case name and number" (United States of America, 1993).This letter was the beginning of the final phase of long-term labor unrest at GTE Supply. The labor conflict began over five years earlier, and culminated in a third union representation election in January 1994.

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