Paleolongitudinal estimates for paleocontinents derived from interplate distances based on Late Ordovician bivalves

Paleobiology ◽  
2011 ◽  
Vol 37 (3) ◽  
pp. 438-444 ◽  
Author(s):  
William F. Schmachtenberg
Keyword(s):  
Regression Analysis ◽  
South America ◽  
Least Squares ◽  
Late Ordovician ◽  
Similarity Analysis ◽  
Least Squares Regression ◽  
Dice Coefficient ◽  
The Past ◽  
Paleoclimatic Data ◽  
Faunal Similarity

The geographic distribution of 293 Modern bivalve genera has been analyzed and found to be statistically correlated with distance. In particular, a least-squares regression analysis of the data indicates that the distance between faunal realms (D) in kilometers can be estimated using the equation D = (ln(d) + 0.4233)/−0.00013, where d is the Dice coefficient of faunal similarity. Analysis of 59 genera of Late Ordovician bivalves indicates that the above equation also describes their biogeographic distribution.Using this formula, the distance between Laurentia and Scotland/Northwest Ireland was estimated to be 5500 kilometers. This is consistent with the reconstruction of a connection among these areas during the Late Ordovician based on brachiopod and graptolite biogeographic data.Paleomagnetic and paleoclimatic data also suggest that Avalonia, Baltica, and Laurentia were at tropical latitudes. Distances between these paleocontinents can therefore be used to estimate paleolongitudes. If the location of England on the eastern side of Avalonia is used as zero degrees paleolongitude for the Late Ordovician as it is today, the paleolongitude for South America, Laurentia, Scotland and northwest Ireland, and Baltica would be 125°W, 45°W, 10°W, and 15°E, respectively. Because of drifting of the Avalonia plate, these paleolongitudes probably do not coincide with the longitudinal grid used today. The paleolongitudes indicate only the relative spacing between continents in the past. The methodology in this study should be useful for improving the accuracy of paleogeographic reconstructions for the Late Ordovician throughout the Cenozoic, and especially the Paleozoic periods for which magnetic seafloor anomaly data are not available.

Inhibition effects of Maillard reaction products derived from l-cysteine and glucose on enzymatic browning catalyzed by mushroom tyrosinase and characterization of active compounds by partial least squares regression analysis

RSC Advances ◽  
2016 ◽  
Vol 6 (70) ◽  
pp. 65825-65836 ◽  
Author(s):  
Haining Xu ◽  
Xiaoming Zhang ◽  
Eric Karangwa
Keyword(s):  
Regression Analysis ◽  
Least Squares ◽  
Maillard Reaction ◽  
Partial Least Squares Regression ◽  
Enzymatic Browning ◽  
Maillard Reaction Products ◽  
Mushroom Tyrosinase ◽  
Least Squares Regression ◽  
Reaction Products

Inhibition of tyrosinase activity by Maillard reaction products derived from cysteine and glucose (Cys-MRPs) was studied.

Contribution of Mindfulness to Individuals' Tendency to Believe and Share Social Media Content

2020 ◽  
pp. 858-878
Author(s):  
Peerayuth Charoensukmongkol
Keyword(s):  
College Students ◽  
Social Media ◽  
Regression Analysis ◽  
Least Squares ◽  
Partial Least Squares ◽  
Media Content ◽  
Positive Contribution ◽  
Full Time ◽  
Direct Link ◽  
Least Squares Regression

The objective of this research was to explore the effect of mindfulness on individuals' tendencies to believe social media content and share it without realizing the potential consequences. The sample used in this study comprised 300 participants in Bangkok, Thailand, of whom 157 were full-time employees and 143 were college students. Results from partial least squares regression analysis supports the hypothesis that individuals who exhibit higher levels of mindfulness tend to be skeptical of the validity of information to which they are exposed. In addition, skepticism is linked to a decreased tendency to believe social media content and to share content on social media. The findings further support a direct link between mindfulness and a decreased tendency to share social media content. Overall, these findings confirm the positive contribution of mindfulness as a quality that may allow individuals to question the validity of social media content before they decide to believe it and share it with others.

Contribution of Mindfulness to Individuals' Tendency to Believe and Share Social Media Content

2016 ◽  
Vol 12 (3) ◽  
pp. 47-63 ◽  
Author(s):  
Peerayuth Charoensukmongkol
Keyword(s):  
College Students ◽  
Social Media ◽  
Regression Analysis ◽  
Least Squares ◽  
Partial Least Squares Regression ◽  
Media Content ◽  
Positive Contribution ◽  
Full Time ◽  
Direct Link ◽  
Least Squares Regression

The objective of this research was to explore the effect of mindfulness on individuals' tendencies to believe social media content and share it without realizing the potential consequences. The sample used in this study comprised 300 participants in Bangkok, Thailand, of whom 157 were full-time employees and 143 were college students. Results from partial least squares regression analysis supports the hypothesis that individuals who exhibit higher levels of mindfulness tend to be skeptical of the validity of information to which they are exposed. In addition, skepticism is linked to a decreased tendency to believe social media content and to share content on social media. The findings further support a direct link between mindfulness and a decreased tendency to share social media content. Overall, these findings confirm the positive contribution of mindfulness as a quality that may allow individuals to question the validity of social media content before they decide to believe it and share it with others.

Asymmetrical patterns of origination and extinction in higher taxa.

Paleobiology ◽  
1987 ◽  
Vol 13 (4) ◽  
pp. 427-445 ◽  
Author(s):  
Norman L. Gilinsky ◽  
Richard K. Bambach
Keyword(s):  
Regression Analysis ◽  
Least Squares ◽  
Stationary Process ◽  
Temporal Trends ◽  
Marine Organisms ◽  
Controlling Factor ◽  
Least Squares Regression ◽  
Higher Taxa

Using Sepkoski's compendium of fossil marine families (1982a, and updates), we have analyzed the changing pace of familial origination and extinction within 55 extinct and 44 extant higher taxa of marine organisms. Eight different metrics were calculated, and least-squares regression analysis was used to identify within-taxon trends in the data. All metrics and analyses gave essentially the same results. Origination metrics decline significantly with time during the histories of higher taxa, while extinction metrics increase significantly. The number of statistically significant declines of origination metric, however, substantially and invariably exceeds the number of statistically significant increases of extinction metric for each pair of corresponding metrics analyzed. It follows, therefore, that temporal trends in the pace of origination and extinction within higher taxa are highly asymmetrical.Further analysis shows that truncating data from temporal endpoints has little effect upon the intensity of origination trends, implying that declining pace of origination is a sustained property of the long term histories of taxa. Such truncation, however, reduces the intensity of extinction trends to statistical insignificance and confirms Van Valen's (1985a) suggestion that extinction behaves largely as a stationary process. If the histories of higher taxa are characterized by substantial declines in the pace of origination while the pace of extinction remains largely stationary, it follows that declining pace of origination is an important controlling factor in long term taxic evolution.

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