scholarly journals Spatial distribution of scalar seismic moment release in Italy (1983-1996): seismotectonic implications for the Apennines

1997 ◽  
Vol 40 (6) ◽  
Author(s):  
G. Selvaggi ◽  
B. Castello ◽  
R. Azzara
Keyword(s):  
Energy Release ◽  
Seismic Moment ◽  
Seismic Energy ◽  
Historical Earthquakes ◽  
Time Interval ◽  
Southern Apennines ◽  
The Past ◽  
Seismic Moment Release ◽  
Narrow Belt ◽  
Seismic Deformation

We analyzed the distribution of seismic moment in Italy, computed from instrumental seismicity recorded by the Italian National Seismic Network in the past 14 years, to map the areas where seismic deformation processes have been active in this time interval. Seismic moment is the most suitable parameter to quantify earthquake size. It is related to the geometric characteristics of faults, to seismic energy and it is a quantity that can be summed and represented in its cumulative value. The maps of seismic moment distribution display more information than epicentral maps, better showing actively deforming regions. They provide further and original evidence for the existence, within the Apenninic belt, of two regions (north and south) characterized by different seismic energy release. The seismic moment is almost continuously and homogeneously distributed all along the belt in the Northern Apennines, whereas in the Southern Apennines it is concentrated in the zones recently activated by mainshock-aftershock seismic sequences. Seismic deformation takes place in a 30 km narrow belt along the Apennines, while in the transition zone between the Northern and Southern Apennines this belt is about 100 km wide. Comparing instrumental seismic moment release with the areas struck by the largest historical earthquakes which have occurred in the past six centuries, we qualitatively extended back to the past the information on where the seismic deformation occurs. In the Southern Apennines background energy release from instrumental seismicity is very low in the several areas hit by large historical earthquakes, suggesting that these seismogenic zones are currently quiescent.

scholarly journals Spatial distribution of horizontal seismic strain in the Apennines from historical earthquakes

1998 ◽  
Vol 41 (2) ◽  
Author(s):  
G. Selvaggi
Keyword(s):  
Seismic Moment ◽  
Recent Literature ◽  
Moment Tensor ◽  
Historical Earthquakes ◽  
Time Interval ◽  
Seismic Moment Tensor ◽  
Southern Apennines ◽  
Seismic Strain Rate ◽  
Seismic Strain ◽  
Main Deformation

Horizontal principal seismic strain rate axes have been calculated within a regular mesh of triangles covering the Italian peninsula in a time interval of 700 years. I have used both the method of Kostrov (1974), that requires knowledge of the seismic moment tensor of earthquakes, and the modified version provided by England and Molnar (1997) that makes use of length and kinematics of the activated faults. Seismic moment tensor of historical earthquakes can be inferred from recent literature, while length of faults has been obtained from the observation that strain drop is almost constant for large Apenninic earthquakes. Spatial strain distribution from historical earthquakes shows that the Apennines can be divided into three homogeneous structural arcs (Northern Apenninic, Southern Apenninic and Calabrian arcs) within which strain is roughly constant. Although NE-SW extension is the main deformation process along the two Apenninic arcs it involves a velocity more than five times greater in the Southern Apennines. Along the Calabrian arc, I tested the effect on the strain field of the contemporaneous ~WNW-ESE and ~NNE-SSW extension due to the longitudinal dilatation of the arc during its still ESE migration.

scholarly journals HISTORICAL EARTHQUAKES IN THE REGION OF LEFKADA ISLAND , IONIAN SEA - ESTIMATION OF MAGNITUDES FROM EPICENTRAL INTENSITIES

2004 ◽  
Vol 36 (3) ◽  
pp. 1389 ◽  
Author(s):  
A. Fokaefs ◽  
G. A. Papadopoulos
Keyword(s):  
Seismic Hazard ◽  
Seismic Hazard Assessment ◽  
Historical Earthquakes ◽  
Maximum Intensity ◽  
16Th Century ◽  
Time Interval ◽  
Ionian Sea ◽  
The Past ◽  
Documentary Sources ◽  
Lefkada Island

Historical documentation of strong shocks for Lefkada Island, Ionian Sea, exists since the 16th century A.D. In this paper we establish a relation between magnitude and maximum intensity from twenty-nine instrumental events that hit the area in the past. Then, on the basis of historical documentary sources we reevaluate the intensities of strong historical earthquakes, their maximum intensity being observed on Lefkada in the time interval from AD1577 to 1911, recalculate their magnitudes on the basis of the magnitude/intensity relation and, finally, compile a new catalogue of historical earthquakes. The results obtained are of importance for the seismicity studies and seismic hazard assessment in the area.

scholarly journals Significant increase in quantity and quality of knee arthroplasty related research in KSSTA over the past 15 years

2021 ◽  
Author(s):  
Stephanie Kirschbaum ◽  
Thilo Kakzhad ◽  
Fabian Granrath ◽  
Andrzej Jasina ◽  
Jakub Oronowicz ◽  
...  
Keyword(s):  
Knee Arthroplasty ◽  
Special Topic ◽  
Computer Assisted ◽  
Time Interval ◽  
Search Term ◽  
Level Of Evidence ◽  
The Past ◽  
Patient Reported ◽  
Over Time ◽  
Number Of Authors

Abstract Purpose This study aimed to evaluate both publication and authorship characteristics in Knee Surgery, Sports Traumatology, Arthroscopy journal (KSSTA) regarding knee arthroplasty over the past 15 years. Methods PubMed was searched for articles published in KSSTA between January 1, 2006, and December 31st, 2020, utilising the search term ‘knee arthroplasty’. 1288 articles met the inclusion criteria. The articles were evaluated using the following criteria: type of article, type of study, main topic and special topic, use of patient-reported outcome scores, number of references and citations, level of evidence (LOE), number of authors, gender of the first author and continent of origin. Three time intervals were compared: 2006–2010, 2011–2015 and 2016–2020. Results Between 2016 and 2020, publications peaked at 670 articles (52%) compared with 465 (36%) published between 2011 and 2016 and 153 articles (12%) between 2006 and 2010. While percentage of reviews (2006–2010: 0% vs. 2011–2015: 5% vs. 2016–2020: 5%) and meta-analyses (1% vs. 6% vs. 5%) increased, fewer case reports were published (13% vs. 3% vs. 1%) (p < 0.001). Interest in navigation and computer-assisted surgery decreased, whereas interest in perioperative management, robotic and individualized surgery increased over time (p < 0.001). There was an increasing number of references [26 (2–73) vs. 30 (2–158) vs. 31 (1–143), p < 0.001] while number of citations decreased [30 (0–188) vs. 22 (0–264) vs. 6 (0–106), p < 0.001]. LOE showed no significant changes (p = 0.439). The number of authors increased between each time interval (p < 0.001), while the percentage of female authors was comparable between first and last interval (p = 0.252). Europe published significantly fewer articles over time (56% vs. 47% vs. 52%), whereas the number of articles from Asia increased (35% vs. 45% vs. 37%, p = 0.005). Conclusion Increasing interest in the field of knee arthroplasty-related surgery arose within the last 15 years in KSSTA. The investigated topics showed a significant trend towards the latest techniques at each time interval. With rising number of authors, the part of female first authors also increased—but not significantly. Furthermore, publishing characteristics showed an increasing number of publications from Asia and a slightly decreasing number in Europe. Level of evidence IV.

Data-driven modeling decadal-to-centennial ENSO variability and its response to external forcing

2021 ◽  
Author(s):  
Aleksei Seleznev ◽  
Dmitry Mukhin ◽  
Andrey Gavrilov ◽  
Alexander Feigin
Keyword(s):  
Co2 Concentration ◽  
Data Driven ◽  
Time Interval ◽  
Solar Forcing ◽  
Russian Science ◽  
Dynamical Mechanism ◽  
Enso Variability ◽  
The Past ◽  
Sst Variability ◽  
Data Driven Modeling

&lt;p&gt;We investigate the decadal-to-centennial ENSO variability based on nonlinear data-driven stochastic modeling. We construct data-driven model of yearly Ni&amp;#241;o-3.4 indices reconstructed from paleoclimate proxies based on three different sea-surface temperature (SST) databases at the time interval from 1150 to 1995 [1]. The data-driven model is forced by the solar activity and CO2 concentration signals. We find the persistent antiphasing relationship between the solar forcing and Ni&amp;#241;o-3.4 SST on the bicentennial time scale. The dynamical mechanism of such a response is discussed.&lt;/p&gt;&lt;p&gt;The work was supported by the Russian Science Foundation (Grant No. 20-62-46056)&lt;/p&gt;&lt;p&gt;1. Emile-Geay, J., Cobb, K. M., Mann, M. E., &amp; Wittenberg, A. T. (2013). Estimating Central Equatorial Pacific SST Variability over the Past Millennium. Part II: Reconstructions and Implications, Journal of Climate, 26(7), 2329-2352.&lt;/p&gt;

scholarly journals Short-term seismic crustal deformation of Iran

2014 ◽  
Vol 57 (2) ◽  
Author(s):  
Shoja Ansari ◽  
Ahmad Zamani
Keyword(s):  
Seismic Moment ◽  
Deformation Rate ◽  
Moment Tensor ◽  
Focal Mechanisms ◽  
Average Strain ◽  
Short Term ◽  
Maximum Shear Strain ◽  
Eastern Iran ◽  
Seismic Deformation ◽  
Orogenic Belts

<p>In this paper the short-term seismic deformation of Iran is determined by the earthquake moment tensor summation. The study areas include the Alborz, Kopeh-Dagh, eastern Iran, Makran and Zagros orogenic belts. The spatial distribution and focal mechanisms of the earthquakes delineate the deformation zones. The mean directions of the P and T axes are determined by the equal area projection of the seismic moment tensors. The orientations of the P-axes are dominantly correlated with the NE crustal motion of Iran relative to Eurasia. The average strain rates are calculated in all of the regions. The maximum shear strain and dilatation rates are defined by the eigenvalues of the average strain rate tensors. The dilatation rate indicates that not only the dominant compression but also the subsidiary tension affects the Alborz and Makran orogenic belts. The velocity tensor components discriminate the vertical thickening and thinning of the crust in some regions of Iran. The seismic deformation rates, which are determined by the velocity tensors, are smaller than the geodetic deformation rates. In the high seismic deformation zones, such as the eastern Iran and Alborz, the geodetic deformation rate is comparable with the seismic deformation rate. Our results indicate that the NW Zagros and Kopeh-Dagh have the lowest seismic deformation rates. The seismic shortening rate increases from NW to SE in the Zagros orogenic belt. The seismic deformation orientations are different from the P-axes, probably due to the lateral translation. The maximum percentage of the seismic deformation in the study areas is related to the eastern Iran and the minimum one is related to the Makran orgenic belt. The average shape tensors indicate that the focal mechanisms in the Kopeh-Dagh have the highest internal similarity. The eastern Iran has the largest seismic moment rate, while the central Zagros has the lowest one.</p>

scholarly journals Five-Year Experience of Liver Transplant at Kerman University of Medical Sciences: Afzalipoor Hospital

2020 ◽  
Author(s):  
Masood Dehghani
Keyword(s):  
Liver Transplantation ◽  
Liver Transplant ◽  
Cross Sectional Study ◽  
Outcome Data ◽  
Time Interval ◽  
Cross Sectional ◽  
The Past ◽  
Transplantation Center ◽  
Set Up ◽  
End Stage

Introduction: The only option for treatment of end stage liver diseases is liver transplantation. Afzalipour Hospital in Kerman, Iran is the third largest liver transplantation center in Iran. In this study, the outcomes of this center have been studied during the past 5 years. Methods: In this cross-sectional study, the pre and post transplantation’s clinical, demographic and outcome data of all patients who received liver transplant at Afzalipour Hospital during the past 5 years have been collected and reviewed. SPSS software ver. 16 was used to analyze the data. Results: Forty-three patients have received liver transplantation during this time interval. The 3-year survival rate of patients was 77%. The most common cause of death was primary nonfunction graft after transplantation. The most common complication was acute rejection (15%), all of which were successfully treated with corticosteroids. Conclusion:  Due to increment of cases of acute and chronic liver failure in the community and since the final treatment of these cases is liver transplantation, so there is need to develop liver transplant centers in the future. Quantitative and qualitative study of the activity of centers based liver transplant in Iran is necessary to set up successful centers.

scholarly journals A Few Binary Star Puzzles for Roberto on the Occasion of His Birthday

2009 ◽  
Vol 26 (3) ◽  
pp. 372-378 ◽  
Author(s):  
George W. Preston
Keyword(s):  
Binary Star ◽  
Carbon Star ◽  
Spectroscopic Binaries ◽  
Velocity Variation ◽  
Time Interval ◽  
Parent Population ◽  
Velocity Amplitude ◽  
The Past ◽  
Binary Separation ◽  
Rr Lyrae

AbstractRadial-velocity observations accumulated during the past 16 years are used to derive a preliminary orbit for the CEMP star CS 22881–036. The velocity amplitude is very small. No velocity variation is found for three additional CEMP stars observed over roughly the same time interval. Searches for companions of two CEMP double-lined spectroscopic binaries and of the RR Lyrae star TY Gru are reviewed. A disparity between the period distribution of disk carbon-star binaries and that of their parent population of normal binaries can be attributed qualitatively to a decline in accreted mass with increasing binary separation. Finally, possible reasons for failure to find expected companions of CEMP stars are discussed.

An application of a stochastic model to a volcanic earthquake swarm

1975 ◽  
Vol 65 (2) ◽  
pp. 351-357
Author(s):  
John Filson ◽  
Tom Simkin
Keyword(s):  
Stochastic Model ◽  
Energy Release ◽  
Earthquake Swarm ◽  
Seismic Energy ◽  
Volcanic Earthquake ◽  
Model Studies ◽  
Seismic Energy Release ◽  
Earthquake Model ◽  
Event Occurrence

abstract The Kolomogorov model of event occurrence as developed by Knopoff in earthquake model studies has been applied to a volcanic earthquake swarm. It is shown that in this case, where the rate of seismic energy release was nearly constant in time, the model adequately relates the various seismicity statistics of the swarm.

scholarly journals Injection‐Induced Seismic Moment Release and Laboratory Fault Slip: Implications for Fluid‐Induced Seismicity

2020 ◽  
Vol 47 (22) ◽  
Author(s):  
Lei Wang ◽  
Grzegorz Kwiatek ◽  
Erik Rybacki ◽  
Marco Bohnhoff ◽  
Georg Dresen
Keyword(s):  
Seismic Moment ◽  
Induced Seismicity ◽  
Fault Slip ◽  
Seismic Moment Release
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