scholarly journals Regional Fluctuations and National Cohesion in the EU12: A Pre-Maastricht Assessment

2013 ◽  
Author(s):  
Francesca Marino
Keyword(s):  
Regional Fluctuations

scholarly journals The Cordilleran Ice Sheet: One Hundred and Fifty Years of Exploration and Discovery

2007 ◽  
Vol 45 (3) ◽  
pp. 269-280 ◽  
Author(s):  
Lionel E. Jackson, ◽  
John J. Clague
Keyword(s):  
World War Ii ◽  
Research Effort ◽  
Ice Sheet ◽  
Early Period ◽  
Transitional Period ◽  
Marine Geology ◽  
Ice Sheet Dynamics ◽  
Cordilleran Ice Sheet ◽  
Regional Fluctuations ◽  
Glacial Landforms

ABSTRACT Present concepts about the Cordilleran Ice Sheet are the product of observations and ideas of several generations of earth scientists. The limits of glaciation in the Cordillera were established in the last half of the nineteenth century by explorers and naturalists, notably G. M. Dawson, R. G. McConnell, and T. C. Chamberlin. By the turn of the century, the gross configuration of the Cordilleran Ice Sheet had been determined, but the causes of glaciation and ice-sheet dynamics remained poorly understood. This early period of exploration and discovery was followed by a transitional period, from about 1900 to 1950, during which a variety of glacial landforms and deposits were explained (e.g., Channeled Scablands of Washington; "white silts" of southern British Columbia), and conceptual models of the growth and decay of the ice sheet were proposed. Shortly after World War II, there was a dramatic increase in research into all aspects of glaciation in the Canadian Cordillera which has continued unabated to the present. Part of the research effort during this period has been directed at resolving the Cordilleran Ice Sheet in both time and space. Local and regional fluctuations of the ice sheet have been reconstructed through stratigraphie and sedimentological studies, supported by radiocarbon and other dating techniques. Compilations of late Pleistocene ice-flow directions have shown that the Cordilleran Ice Sheet was a mass of coalescent glaciers flowing in a complex fashion from many montane source areas. During the postwar period, research has also begun or advanced significantly in several other disciplines, notably glaciology, process sedimen-tology, geomorphology, paleoecology, and marine geology. Attempts are now being made to quantitatively model the Cordilleran Ice Sheet using computers and the geological database assembled by past generations of earth scientists.

scholarly journals A novel hyperthermophilic methylglyoxal synthase: molecular dynamic analysis on the regional fluctuations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Gyo-Yeon Seo ◽  
Hoe-Suk Lee ◽  
Hyeonsoo Kim ◽  
Sukhyeong Cho ◽  
Jeong-Geol Na ◽  
...  
Keyword(s):  
Protein Structure ◽  
Hydrogen Bonds ◽  
Root Mean Square ◽  
Residual Activity ◽  
Dynamics Simulation ◽  
Mean Square ◽  
Salt Bridges ◽  
Optimum Activity ◽  
Regional Fluctuations ◽  
Methylglyoxal Synthase

AbstractTwo putative methylglyoxal synthases, which catalyze the conversion of dihydroxyacetone phosphate to methylglyoxal, from Oceanithermus profundus DSM 14,977 and Clostridium difficile 630 have been characterized for activity and thermal stability. The enzyme from O. profundus was found to be hyperthermophilic, with the optimum activity at 80 °C and the residual activity up to 59% after incubation of 15 min at 95 °C, whereas the enzyme from C. difficile was mesophilic with the optimum activity at 40 °C and the residual activity less than 50% after the incubation at 55 °C or higher temperatures for 15 min. The structural analysis of the enzymes with molecular dynamics simulation indicated that the hyperthermophilic methylglyoxal synthase has a rigid protein structure with a lower overall root-mean-square-deviation value compared with the mesophilic or thermophilic counterparts. In addition, the simulation results identified distinct regions with high fluctuations throughout those of the mesophilic or thermophilic counterparts via root-mean-square-fluctuation analysis. Specific molecular interactions focusing on the hydrogen bonds and salt bridges in the distinct regions were analyzed in terms of interatomic distances and positions of the individual residues with respect to the secondary structures of the enzyme. Key interactions including specific salt bridges and hydrogen bonds between a rigid beta-sheet core and surrounding alpha helices were found to contribute to the stabilisation of the hyperthermophilic enzyme by reducing the regional fluctuations in the protein structure. The structural information and analysis approach in this study can be further exploited for the engineering and industrial application of the enzyme.

Cross-Sectional, Time-Series Issues in the Analysis of Marketing Decision Variables

1975 ◽  
Vol 12 (2) ◽  
pp. 142-150 ◽  
Author(s):  
Mark Moriarty
Keyword(s):  
Time Series ◽  
Market Share ◽  
Variance Components ◽  
Policy Formulation ◽  
Time Series Model ◽  
Cross Sectional ◽  
Empirical Results ◽  
Marketing Decision ◽  
Decision Variables ◽  
Regional Fluctuations

A variance components cross-sectional, time-series model is presented for use in the analysis of marketing decision variables. Empirical results suggest that the model's disaggregative form offers advantages for policy formulation particularly where regional fluctuations in market share are significant.

Sign in / Sign up

Export Citation Format

Share Document