Erratum: Dynamic Chemical Equilibrium in a Polar Desert Pond: A Sensitive Index of Meteorological Cycles

Science ◽  
1979 ◽  
Vol 204 (4396) ◽  
pp. 909-909
Keyword(s):  
Chemical Equilibrium ◽  
Polar Desert ◽  
Sensitive Index

Dynamic Chemical Equilibrium in a Polar Desert Pond: A Sensitive Index of Meteorological Cycles

Science ◽  
1979 ◽  
Vol 204 (4390) ◽  
pp. 301-303 ◽  
Author(s):  
H. J. H. HARRIS ◽  
K. CARTWRIGHT ◽  
T. TORII
Keyword(s):  
Chemical Equilibrium ◽  
Polar Desert ◽  
Sensitive Index

Control of chemical equilibrium through optical pumping

1985 ◽  
Vol 10 (6) ◽  
pp. 883-891 ◽  
Author(s):  
M. Allegrini ◽  
G. Alzetta ◽  
P. Bicchi ◽  
S. Gozzini ◽  
L. Moi
Keyword(s):  
Chemical Equilibrium ◽  
Optical Pumping

Demonstration and Quantitation of Pharmacological Inhibition of Pulmonary Uptake of N-lsopropyl-123l-p-lodoamphetamine by Propranolol

1989 ◽  
Vol 28 (03) ◽  
pp. 100-104 ◽  
Author(s):  
S. F. Akber
Keyword(s):  
Binding Sites ◽  
Bolus Injection ◽  
Cell Function ◽  
Lung Pathology ◽  
Lung Uptake ◽  
Pharmacological Inhibition ◽  
Sensitive Index ◽  
Pulmonary Uptake ◽  
First Pass

The first-pass pulmonary extraction values of N-lsopropyl-123l-p-lodoamphetamine (123I-IMP) in pretreated dogs decreases from 90 to 62% as the amount of propranolol increases from 0 to 20 mg. The first-pass pulmonary extraction values of 123I-IMP in dogs with a simultaneous bolus injection of propranolol decreases from 90 to 62% as the amount of propranolol increases from 0 to 10 mg. The pulmonary extraction of 123I-IMP with a simultaneous bolus injection of ketamine and 123I-IMP decreases from 90 to 64% as the ketamine dose increases from 0 to 100 mg. These results suggest that the pulmonary uptake of 123I-IMP may be at least partially mediated by receptors. They also indicate that endothelial metabolic cell function may be a useful index of early lung pathology. Furthermore, studies of the degree of lung uptake may be a sensitive index of pathologic states in which alterations of amine binding sites have occurred.

Vegetation of the southern part of Bolshevik Island (Severnaya Zemlya Archipelago)

2006 ◽  
pp. 3-87 ◽  
Author(s):  
N. V. Matveyeva
Keyword(s):  
Coastal Plain ◽  
Great Majority ◽  
Wide Distribution ◽  
Tundra Zone ◽  
Polar Desert ◽  
Character Species ◽  
Severnaya Zemlya ◽  
Severnaya Zemlya Archipelago ◽  
Desert Zone ◽  
Ecological Range

Bolshevik Isl. is the one of the largest islands within the Severnaya Zemlya archipelago. It is situated in the southern part of the polar desert zone. In the course of three field work trips in 1997, 1998 and 2000 years 252 relevees were made in its southern part on three geomorphologic surfaces: coastal plain, inner upland close to glacier and ancient high river terraces. As the result 27 syntaxonomical units of different rank (15 associations, 2 subassociations, 2 variants, and 8 community types) were described using Braun-Blanquet approach. All syntaxa, except one, are new and mostly similar to communities described on Franz Josef Land. The problems were to put new syntaxa into the higher level units (including class) within the syntaxonomical hierarchy. The main bulk of syntaxa, both zonal and intrazonal ones, has to be preliminary placed into Salicetea herbaceae class although there is a lot of reasons to consider zonal syntaxa as a new class that is specific for the polar desert zone. In any case, there are no one syntaxon that can be referred to Loiseleurio-Vaccinietea class that combines zonal vegetation in the tundra zone. The wide ecological range of great majority of species as well as the changes of their intralandscape distribution compare to the tundra zone made additional difficulties in finding character and differential species. 340 species (vascular plants — 52, mosses — 97, liverworts — 41, lichens — 150), that compiles 73 % of the whole island flora and 84 % of its southern part, were recorded within the all relevees. Almost half of these (182) are very rare on the island and 127 species were met 1—2 times. There are 70 species with wide ecological range throughout all landscape types with such commonly distributed herbs as Saxifraga cernua, S. hyperborea and Stellaria ed­ward­sii, mosses Polytrichastrum alpinum and Sanionia uncinata and lichen Stereocaulon rivulorum among these. Phippsia algida, the character species for snow bed communities, occurs in about 70 % of syntaxa. Useful for differentiation of syntaxa have been appeared 87 species. Few species with wide distribution within a landscape demonstrate their preference to a certain syntaxon by higher abundance (preferential character species). These are mostly bryophytes: mosses Bryum cryophilum and Grimmia torquata, and liver­worts Gymnomitrion corallioides, Marsupella arctica and Scapania crassiretis. Cryptogam species predo­minate in the whole flora as well as in each syntaxon. The number of species varies from 12 to 70 per sample plots 5÷5 m and from 20 to 195 in different syntaxa. The richest in species (70 per community and about 190 for association) are zonal plant communities on the accumulative coastal plain in the region of Sol­nechnaya Bay, the poorest one, with 10 and 20 species consequently, is ass. Hygrohypno polari—Saxifragetosum hyperboreae that was described on the upland, close to glacier in the inner part of island.

Developing a Three-Tier Diagnostic Instrument on Chemical Equilibrium (TT-DICE)

2020 ◽  
Vol 31 (3) ◽  
pp. 84
Author(s):  
J. Jusniar ◽  
E. Effendy ◽  
Endang Budiasih ◽  
S. Sutrisno
Keyword(s):  
High School Students ◽  
Chemical Equilibrium ◽  
Diagnostic Instrument ◽  
Difficulty Level ◽  
Literature Study ◽  
School Students ◽  
Development Models ◽  
High Category ◽  
Third Stage ◽  
Very High

<p class="p1"><span class="s1">This study aims to develop a Three-tier Diagnostic Instrument on Chemical Equilibrium (TT-DICE) to diagnose high school students’ misconceptions related to this topic. TT-DICE consists of thirty items, asking for students’ answers, reasonings, and levels of confidence. Three-stages development models developed by Treagust applied in developing TT-DICE. First-stage was a literature study to analyze the main concepts and students’ misconceptions in CE. The next step is the development of the TT-DICE prototype, consisting of item development, preliminary experiments, interviews, and revisions. The third stage of validity checking starts with content validation by experts and practitioners. A field test conducted to determine the reliability and quality variables are supporting TT-DICE items. These variables are Item Validity (IV), Difficulty Level (DL), Discrimination Index (DI), and effectiveness of distractors. Content validity by validators showed that the TT-DICE is valid with a very high category (96.1%). The results of item validity show that 88.9% of the items are valid. Testing of DL, DI, and the effectiveness of distractors in general, shows a good category. The Reliability of the three-tiers TTDICE using Alpha Cronbach is a high and very high category, respectively (0.83, 0.81 &amp; 0.91). The overall validity test results also concluded if the TT-DICE is valid, reliable, and suitable to diagnose misconceptions of Chemical Equilibrium.</span></p>

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