Field Intensity changes during the past 40 ka

2020 ◽  
Author(s):  
Jean-Pierre Valet ◽  
Franck Bassinot ◽  
Ramon Egli ◽  
Anojh Thevarasan
Keyword(s):  
Dipole Moments ◽  
Field Vector ◽  
Historical Period ◽  
Directional Information ◽  
Sedimentary Records ◽  
Axial Dipole ◽  
The Past ◽  
Intensity Changes ◽  
Volcanic Lava

<p>The period encompassing the past 40 ka is crucial to constrain the characteristic time of the axial dipole, which is computed so far from the historical period and still fails to be tested against long-term field changes. The past 7 kyr of geomagnetic history are primarily documented from archeological artefacts, yet the last 4 kyr remain relatively poorly constrained. Beyond this period, we are dealing with long-term changes of the dipole field that are relatively poorly documented by sedimentary records or by volcanic lava flows. Many measurements of absolute paleointensity do not incorporate directional information, while it is crucial to document the entire field vector and consequently can only be analyzed in terms of virtual axial dipole moments (VADM). In summary, no high resolution dataset covers the field changes which followed the Laschamp event and therefore we have poor knowledge of the pattern of fluctuations and the rate of the changes that were associated with the field recovery after the Laschamp. We have selected a set of marine sedimentary cores based on the quality of their oxygen isotope records. Their deposition rates are comprised between 10 and 20 cm/ka and therefore offer a great potential to constrain the filed intensity changes with a resolution of the order of 100 ka. during this period. We will present the results obtained from 7 marine core records and investigate their common and their discrepant features in order to identify the true paleointensity signal.</p><p> </p>

scholarly journals Weaker axially dipolar time-averaged paleomagnetic field based on multidomain-corrected paleointensities from Galapagos lavas

2015 ◽  
Vol 112 (49) ◽  
pp. 15036-15041 ◽  
Author(s):  
Huapei Wang ◽  
Dennis V. Kent ◽  
Pierre Rochette
Keyword(s):  
Field Strength ◽  
Mean Field ◽  
Axial Dipole ◽  
The Past ◽  
Galapagos Archipelago ◽  
The Earth ◽  
Geocentric Axial Dipole ◽  
Dynamo Process ◽  
Comprehensive Study

The geomagnetic field is predominantly dipolar today, and high-fidelity paleomagnetic mean directions from all over the globe strongly support the geocentric axial dipole (GAD) hypothesis for the past few million years. However, the bulk of paleointensity data fails to coincide with the axial dipole prediction of a factor-of-2 equator-to-pole increase in mean field strength, leaving the core dynamo process an enigma. Here, we obtain a multidomain-corrected Pliocene–Pleistocene average paleointensity of 21.6 ± 11.0 µT recorded by 27 lava flows from the Galapagos Archipelago near the Equator. Our new result in conjunction with a published comprehensive study of single-domain–behaved paleointensities from Antarctica (33.4 ± 13.9 µT) that also correspond to GAD directions suggests that the overall average paleomagnetic field over the past few million years has indeed been dominantly dipolar in intensity yet only ∼60% of the present-day field strength, with a long-term average virtual axial dipole magnetic moment of the Earth of only 4.9 ± 2.4 × 1022 A⋅m2.

Time Trends in Social Class Mortality Differentials in the Netherlands, 1820–1920

2009 ◽  
Vol 33 (2) ◽  
pp. 119-153
Author(s):  
Frans van Poppel ◽  
Roel Jennissen ◽  
Kees Mandemakers
Keyword(s):  
Social Class ◽  
The Netherlands ◽  
Adult Mortality ◽  
Living Standards ◽  
Theoretical Issue ◽  
Historical Period ◽  
The Past ◽  
Long Term Trends ◽  
Using Data

The question whether socioeconomic status gradients in adult mortality have changed over a broad historical period has become an important political and theoretical issue but is hard to test. In this article we study long-term trends in social inequality in adult mortality by using data for 2 (of the 11) provinces of the Netherlands for the period 1812–1922. We apply indirect estimation techniques, which have been developed for the analysis of mortality patterns in countries with deficient data. Our article shows that indeed there was a clear social class gradient in mortality, with the elite having higher survival chances between ages 35 and 55 than the middle class and farmers. Differences were even more apparent in comparison with workers. Over time there was a strong convergence among social classes in mortality levels. The implications of our results for the dominant views on the change in living standards in the past are discussed.

scholarly journals The historic reality of the cyclonic variability in French Antilles, 1635–2007

2015 ◽  
Vol 11 (2) ◽  
pp. 1519-1550 ◽  
Author(s):  
E. Garnier ◽  
J. Desarthe ◽  
D. Moncoulon
Keyword(s):  
Climate Change ◽  
Natural Disasters ◽  
Historical Period ◽  
The Past ◽  
French Antilles ◽  
Evolution Analysis ◽  
Historical Archives ◽  
Disaster Severity ◽  
First Time

Abstract. Facing climate change and increasing costs of natural disasters, the exposure evolution analysis requires having a long-term knowledge of the impacts of extreme events. By associating historical and modeling approaches, we aim to build a long term chronology of natural disaster severity and damages. To highlight this new methodology, the overseas departments of French Antilles have been chosen. These territories are strongly exposed to natural disasters, particularly hurricanes. The search with historical archives made it possible to reconstruct, for the first time, the chronology and severity of hurricanes since the 17th century. During the 20th century, a significative increase in the number of cyclones has occurred after the 1950s. The analysis of a longer historical period (since the 1630s) allows us to temperate this idea by showing intensive cyclonic period in the past centuries.

Enabling Community Well-being Self-Monitoring in the Context of Mining: The Naskapi Nation of Kawawachikamach

2016 ◽  
Vol 1 (2) ◽  
Author(s):  
Robert Klinck ◽  
Ben Bradshaw ◽  
Ruby Sandy ◽  
Silas Nabinacaboo ◽  
Mannie Mameanskum ◽  
...  
Keyword(s):  
Indigenous Peoples ◽  
Well Being ◽  
Aboriginal Community ◽  
Self Monitoring ◽  
Community Engaged Research ◽  
The Past ◽  
Mineral Development ◽  
Iron Deposits ◽  
Term Monitoring

The Naskapi Nation of Kawawachikamach is an Aboriginal community located in northern Quebec near the Labrador Border. Given the region’s rich iron deposits, the Naskapi Nation has considerable experience with major mineral development, first in the 1950s to the 1980s, and again in the past decade as companies implement plans for further extraction. This has raised concerns regarding a range of environmental and socio-economic impacts that may be caused by renewed development. These concerns have led to an interest among the Naskapi to develop a means to track community well-being over time using indicators of their own design. Exemplifying community-engaged research, this paper describes the beginning development of such a tool in fall 2012—the creation of a baseline of community well-being against which mining-induced change can be identified. Its development owes much to the remarkable and sustained contribution of many key members of the Naskapi Nation. If on-going surveying is completed based on the chosen indicators, the Nation will be better positioned to recognize shifts in its well-being and to communicate these shifts to its partners. In addition, long-term monitoring will allow the Naskapi Nation to contribute to more universal understanding of the impacts of mining for Indigenous peoples.

Courting the Youth Vote in 2008: The Obama Effect

2009 ◽  
Vol 5 ◽  
Author(s):  
Lindsey C Bohl
Keyword(s):  
Presidential Elections ◽  
Voter Registration ◽  
The Internet ◽  
The Past ◽  
Several Variables ◽  
High Turnout ◽  
Short And Long Term ◽  
Use Of The Internet ◽  
Youth Vote

This paper examines a few of the numerous factors that may have led to increased youth turnout in 2008 Election. First, theories of voter behavior and turnout are related to courting the youth vote. Several variables that are perceived to affect youth turnout such as party polarization, perceived candidate difference, voter registration, effective campaigning and mobilization, and use of the Internet, are examined. Over the past 40 years, presidential elections have failed to engage the majority of young citizens (ages 18-29) to the point that they became inclined to participate. This trend began to reverse starting in 2000 Election and the youth turnout reached its peak in 2008. While both short and long-term factors played a significant role in recent elections, high turnout among youth voters in 2008 can be largely attributed to the Obama candidacy and campaign, which mobilized young citizens in unprecedented ways.

Impact of FII’s and FDI’s on Indian Stock Market

2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Dr. Kamlesh Kumar Shukla
Keyword(s):  
Stock Market ◽  
Financial Markets ◽  
Global Economy ◽  
Short Term ◽  
Earnings Growth ◽  
The Past ◽  
Bull Market ◽  
Indian Stock Market

FIIs are companies registered outside India. In the past four years there has been more than $41 trillion worth of FII funds invested in India. This has been one of the major reasons on the bull market witnessing unprecedented growth with the BSE Sensex rising 221% in absolute terms in this span. The present downfall of the market too is influenced as these FIIs are taking out some of their invested money. Though there is a lot of value in this market and fundamentally there is a lot of upside in it. For long-term value investors, there’s little because for worry but short term traders are adversely getting affected by the role of FIIs are playing at the present. Investors should not panic and should remain invested in sectors where underlying earnings growth has little to do with financial markets or global economy.

Chinese Medicine Protein and Peptide in Gene and Cell Therapy

2019 ◽  
Vol 20 (3) ◽  
pp. 251-264 ◽  
Author(s):  
Yinlu Feng ◽  
Zifei Yin ◽  
Daniel Zhang ◽  
Arun Srivastava ◽  
Chen Ling
Keyword(s):  
Chinese Medicine ◽  
Cell Therapy ◽  
Future Research ◽  
The Past ◽  
Promising Strategy ◽  
Wide Range ◽  
New Directions ◽  
Gene And Cell Therapy ◽  
Proteins And Peptides

The success of gene and cell therapy in clinic during the past two decades as well as our expanding ability to manipulate these biomaterials are leading to new therapeutic options for a wide range of inherited and acquired diseases. Combining conventional therapies with this emerging field is a promising strategy to treat those previously-thought untreatable diseases. Traditional Chinese medicine (TCM) has evolved for thousands of years in China and still plays an important role in human health. As part of the active ingredients of TCM, proteins and peptides have attracted long-term enthusiasm of researchers. More recently, they have been utilized in gene and cell therapy, resulting in promising novel strategies to treat both cancer and non-cancer diseases. This manuscript presents a critical review on this field, accompanied with perspectives on the challenges and new directions for future research in this emerging frontier.

Organizational Reforms as Routines

2017 ◽  
Author(s):  
Nils Brunsson
Keyword(s):  
Long Term Effects ◽  
The Past ◽  
Limited Experience

This chapter argues that organizational reforms are driven by problems to be addressed, by solutions to be applied, and by forgetfulness. The greater the supply of any of these factors, the more likely it is that reforms will occur. Without problems, reforms are difficult to justify; without solutions they cannot be formulated; and without forgetfulness there is a risk that people will be discouraged by the fact that similar reforms have been tried and have failed in the past. In contemporary large organizations, problems tend to be easily found. Those interested in selling solutions often try to supply problems as well — problems that can be solved by their solutions. Forgetfulness can be promoted by the use of consultants with limited experience of the implementation and long-term effects of reforms. Reforms are also self-referential; they tend to cause new reforms. Thus, reforms can be considered as routines: they are likely to be repeated over and over again.

Concussion, neuroethics, and sport: Policies of the past do not suffice for the future

2017 ◽  
Author(s):  
Brad Partridge ◽  
Wayne Hall
Keyword(s):  
Mental Health ◽  
Head Trauma ◽  
Mental Health Problems ◽  
Ethical Issues ◽  
Cognitive Impairments ◽  
Concussion Management ◽  
Design And Implementation ◽  
The Past ◽  
Management Policies

Concussion management policies have become a major priority worldwide for sports that involve frequent collisions between participants because repeated head trauma has been associated with long-term cognitive impairments, mental health problems, and some forms of neurological degeneration. A number of concussion management policies have been developed by professional bodies and subsequently adopted by various sporting leagues. These have offered little guidance on how to navigate ethical issues in identifying and managing concussion. This chapter discusses ethical issues that arise in the diagnosis of concussion, debates about the longer-term consequences of repeated concussion injuries, and the design and implementation of policies that aim to prevent and manage concussion injuries in sporting matches.

Increase associated risk of gynaecological cancer due to long-term exposure to high concentration of atmospheric SO2 industrial pollutant

2021 ◽  
pp. 1420326X2110036
Author(s):  
Qian Xu ◽  
Chan Lu ◽  
Rachael Gakii Murithi ◽  
Lanqin Cao
Keyword(s):  
Time Windows ◽  
Air Pollutant ◽  
Gynaecological Cancer ◽  
High Concentration ◽  
The Past ◽  
Short And Long Term ◽  
Using Data ◽  
Air Quality Monitoring Stations ◽  
Control Study

A cohort case–control study was conducted in XiangYa Hospital, Changsha, China, which involved 305 patients and 399 healthy women, from June 2010 to December 2018, to evaluate the association between Chinese women’s short- and long-term exposure to industrial air pollutant, SO2 and gynaecological cancer (GC). We obtained personal and family information from the XiangYa Hospital electronic computer medical records. Using data obtained from the air quality monitoring stations in Changsha, we estimated each woman’s exposure to the industrial air pollutant, sulphur dioxide (SO2), for different time windows, including the past 1, 5, 10 and 15 years before diagnosis of the disease. A multiple logistic regression model was used to assess the association between GC and SO2 exposure. GC was significantly associated with long-term SO2 exposure, with adjusted odds ratio (95% confidence interval) = 1.56 (1.10–2.21) and 1.81 (1.07–3.06) for a per interquartile range increase in the past 10 and 15 years, respectively. Sensitivity analysis showed that different groups reacted in different ways to long-term SO2 exposure. We concluded that long-term exposure to high concentration of industrial pollutant, SO2 is associated with the development of GC. This finding has implications for the prevention and reduction of GC.

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