From Gaul to Francia

Author(s):  
Paul Fouracre

The ways in which “Gaul” became “Francia” have been regarded as key to the development of Europe as a whole during the Middle Ages and beyond. This has led to a “Francocentric” view of west European history. This chapter considers how that view was constructed from a canon of narrative and normative sources. It examines the emergence of a Frankish polity and asks why that polity was so large. It then considers why the Frankish kingdoms did not disintegrate over the course of the seventh century, given the political conflict evident in the later narrative sources. The aristocracy and the church were considered cohesive as well as disruptive forces. A high level of social, political, cultural, and religious integration against a background of diminishing economic resources is seen as central to long-term stability in the polity. Shorter-term outbreaks of violence are analyzed in terms of factional politics that ultimately worked to restore balance. The chapter closes with a discussion of how the balance of power was finally upset, leading to the demise of the Merovingian dynasty and the rise of the Carolingians. Emphasis, however, is given to the strong cultural and religious continuities that were the fruit of a long period of stability and that became the basis of Carolingian power.

Author(s):  
Masashi Nakayama ◽  
Haruo Sato ◽  
Yutaka Sugita ◽  
Seiji Ito ◽  
Masashi Minamide ◽  
...  

In Japan, any high level radioactive waste (HLW) repository is to be constructed at over 300 m depth below surface. Tunnel support is used for safety during the construction and operation, and shotcrete and concrete lining are used as the tunnel support. Concrete is a composite material comprised of aggregate, cement and various admixtures. Low alkaline cement has been developed for the long term stability of the barrier systems whose performance could be negatively affected by highly alkaline conditions arising due to cement used in a repository. Japan Atomic Energy Agency (JAEA) has developed a low alkaline cement, named as HFSC (Highly Fly-ash Contained Silicafume Cement), containing over 60 wt% of silica-fume (SF) and fly-ash (FA). HFSC was used experimentally as the shotcrete material in construction of part of the 140m deep gallery in the Horonobe Underground Research Laboratory (URL). The objective of this experiment was to assess the performance of HFSC shotcrete in terms of mechanics, workability, durability, and so on. HFSC used in this experiment is composed of 40 wt% OPC (Ordinary Portland Cement), 20 wt% SF, and 40 wt% FA. This composition was determined based on mechanical testing of various mixes of the above components. Because of the low OPC content, the strength of HFSC tends to be lower than that of OPC. The total length of tunnel using HFSC shotcrete is about 73 m and about 500 m3 of HFSC was used. The workability of HFSC shotcrete was confirmed in this experimental construction.


1981 ◽  
Vol 11 ◽  
Author(s):  
T. J. Headley ◽  
G. W. Arnold ◽  
C. J. M. Northrup

The long-term stability of nuclear waste forms is an important consideration in their selection for safe disposal of radioactive waste. Stability against long-term radiation damage is particularly difficult to assess by short-term laboratory experiments. Much of the displacement damage in high-level waste forms will be generated by heavy recoil nuclei emitted during the α-decay process of long-lived actinide elements. Hence, an accelerated aging test which reliably simulates the α-recoil damage accumulated during thousands of years of storage is desirable. One recent approach to this simulation is to implant the waste form with heavy Pb-ions.I- 6 If the validity of this approach is to be fully assessed, two important questions which have not yet been investigated must be answered.(1) Is the structural damage, including cumulative effects, similar for irradiation by Pb-ions and a-recoil nuclei in a given material? (2) Is the dose-dependence of the accumulated damage similar? The purpose of this investigation was to assess the extent of these similarities in selected materials. We utilized transmission electron microscopy (TEM) to characterize the radiation damage and measure its dose-dependence.


2019 ◽  
Vol 22 (2) ◽  
pp. 147-154
Author(s):  
Alessandra De Carvalho Moreira ◽  
Jhenifer Rodrigues Silva ◽  
Renata De Paula Samico ◽  
Gabriela Nogueira de Melo Nishioka ◽  
Renato Sussumu Nishioka

Objetivo: Bio-Oss is a xenogene bone graft in which all organic components are removed while retaining their natural mineral architecture. Therefore, the aim of this study was to evaluate, through a literature review, the benefits of using Bio-Oss for tissue regenerative treatment prior to implant placement. Material and Methods: a search was performed in Pubmed (Medline) in order to identify articles published in English between January 1, 2000 and June 31, 2018, where the Bio-Oss graft was used prior to implantation of implants in humans. A total of 40 studies were selected for detailed analysis. From this analysis, 18 articles were identified for inclusion in this review. Results: the articles analyzed in the review showed several beneficial effects of this xenograft, such as: positive osteoconductive properties, recovery of bone heights at sites with severe atrophies, slow xenograft reabsorption suggesting long term stability, survival rates and success of implants placed in grafted sites ranging from 91 to 100% in several studies. Conclusion: the use of bio-oss as a bone substitute is a viable alternative in the placement before dental implants, being used in clinical practice and with proved efficacy in several studies, due to its similarity with the bone and its high level of osteoconductivity.KeywordsBio-Oss; Bone Graft; Implants.


1997 ◽  
Vol 506 ◽  
Author(s):  
M. Steinmann ◽  
P. Stille ◽  
K. Mengel ◽  
M. Siemann ◽  
W. Bernotat

Basaltic dykes in salt rocks can be used in two different ways as natural analogues for high level radioactive waste (HLW) in a salt repository: In the first approach the basalts serve as analogues for the corrosion behavior of HiLW glass products during millions of years because of many similarities in their physical and chemical properties.


2019 ◽  
Vol 482 (1) ◽  
pp. 301-312 ◽  
Author(s):  
Masao Uyama ◽  
Takashi Hitomi ◽  
Sayaka Hayagane ◽  
Naoe Kadota ◽  
Hiroyuki Saito ◽  
...  

AbstractGeological disposal is the most realistic option for high-level radioactive waste in Japan. In considering long-term stability for geological disposal, several types of materials have been studied as engineered barriers with a host rock. We focused our study on metal and bentonite as engineered barrier materials and investigated the long-term corrosion tendency of the metal exposed to bentonite. An electrochemical method for inducing accelerated corrosion was studied in a laboratory, and we analysed some field samples from a FEBEX dismantling project (FEBEX-DP) in Switzerland for comparison with our experimental results.


The Condor ◽  
2001 ◽  
Vol 103 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Robert M. Zink ◽  
Ann E. Kessen ◽  
Theresa V. Line ◽  
Rachelle C. Blackwell-Rago

Abstract We compared mitochondrial DNA sequences for six species distributed across the aridlands of North America to document phylogeographic patterns and assess levels of congruence. The Curve-billed Thrasher (Toxostoma curvirostre) and Canyon Towhee (Pipilo fuscus) show genetic divisions between the Sonoran and Chihuahuan Deserts, whereas the Cactus Wren (Campylorhynchus brunneicapillus), Black-tailed Gnatcatcher (Polioptila melanura), and Verdin (Auriparus flaviceps) do not. Most likely, species without phylogeographic structure only recently colonized their entire current range. Therefore, although these species are today part of a widespread avifauna, species' distributions were historically different from today. In Baja California, the Cactus Wren and the Verdin show phylogeographic breaks at 28°–30°N, consistent with a division previously described in the LeConte's Thrasher (Toxostoma lecontei) and in some members of the herpetofauna. These genetic divisions were likely caused by isolation resulting from a mid-peninsular seaway that existed one million years ago. Hence, these species appear to have been broadly sympatric for at least one million years. In contrast, the California Gnatcatcher (Polioptila californica) lacks such a phylogeographic division, and apparently only recently expanded into the northern part of its current range. Thus, not all species in Baja California have had similar histories, although further sampling might reveal a general pattern. Comparative phylogeography therefore provides an indirect method of evaluating the long-term stability of faunas via assessment of levels of phylogeographic congruence, and can show whether particular species are likely to have had a long period of co-association.


2019 ◽  
Vol 126 (4) ◽  
pp. 528
Author(s):  
В.К. Битюков ◽  
Р.А. Горбунов ◽  
Д.С. Симачков ◽  
А.В. Фрунзе

In spectroscopy, hollow cathode lamps are subject to increased requirements on radiation parameters. In order to perform verification of such lamps a highly stable source of spectral lines is needed, the intensity of which on the spectral lines will remain unchanged (≤1%) for a long time. A solution to this problem is proposed and a scheme of an experimental bench for a hollow cathode lamp with a negative feedback loop is presented. The developed device is used in control circuit, which is a highly stable source of spectral lines and a specialized power supply unit. The results of the experimental study along with metrological analysis are presented. The proposed technical solution in terms of developing a stable source of spectral lines made it possible to obtain a high level of both short-term and long-term stability of the spectral lines.


Author(s):  
Marcelo Malisano Barreto Filho ◽  
Melissa Walker ◽  
Matt P. Ashworth ◽  
J. Jeffrey Morris

Natural microbial communities are extremely complex, with many more species coexisting in the same place than there are different resources to support them. Understanding the forces that allow this high level of diversity has been a central focus of ecological and evolutionary theory for many decades.


2019 ◽  
Vol 13 (4) ◽  
pp. 663-671
Author(s):  
Hannah Wild ◽  
Pierre Fallavier ◽  
Ronak Patel

ABSTRACTWhat began in 2013 as the eruption of a political struggle between forces loyal to President Salva Kiir, a member of the Dinka ethnic group, and then–vice president Riek Machar, a Nuer, has splintered into a multifaction conflict. A dizzying array of armed groups have entered the fray, many unmotivated by political leverage that conventionally brings parties to a conflict to the negotiating table. Two years and tens of thousands of deaths after the 2015 signing of the Agreement on the Resolution of the Conflict in South Sudan, with no substantive progress toward meetings its terms, it is unrealistic to think that Intergovernmental Authority on Development’s recently announced High-Level Revitalization Forum will be sufficient to address the drivers of this conflict. Current policy proposals are poorly designed to address escalating intercommunal conflict and cattle raiding, both devastating forms of violence. As measures at the international level continue to be pursued, the conflict resolution strategy should also include a more comprehensive approach incorporating local actors in order to build momentum toward long-term stability. In this article, we highlight gaps in the current dialogue around a political solution in South Sudan, as well as domains that must be part of the next push for peace. (Disaster Med Public Health Preparedness. 2019;13:663–671)


2001 ◽  
Vol 65 (5) ◽  
pp. 589-601 ◽  
Author(s):  
D. Read ◽  
C. T. Williams

AbstractThis paper provides a brief perspective on synthetic, phosphate-based waste forms for high level radioactive waste (HLW). Evidence in support of their long-term stability is then discussed by reference to the degradation of natural monazites with emphasis on the fate of released uranium, thorium and the rare earths (REE). It is apparent that the REE can be mobilized and fractionated at temperatures anticipated in a HLW repository (∼200°C). This provides an indication of the likely fate of the trivalent actinides (Am(III), Cm(III)) if incorporated in similar matrices. Thorium, though released on alteration of monazite, tends to re-concentrate locally in secondary, microcrystalline phases. In relative terms, U is readily removed from monazites. Although it can be re-concentrated in alteration products, the potential exists for substantial loss of U to groundwater. The findings of this research have important implications for the performance of radioactive waste disposal systems where there is a clear need for improved chemical data to describe the precipitation-dissolution of phosphate phases. It is concluded that monazite-like ceramics designed for the containment of HLW will retain tetravalent actinides but may release uranium in response to natural degradative processes.


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