bluuebunny/crossref_metadata_2025 huggingface dataset:
The Barriers to Proletarianization: Bolivian Mine Labour, 1826–1918
Authors: Langer Erick D.
Published: February 2009

Labour history in Latin America has, to a great degree, followed the models set by the rich historiography in Europe and North America. Other than a justifiable concern with the peculiarities in production for export of primary goods, much of the Latin American historiography suggests that the process of labour formation was rather similar to that of the North Atlantic economies, only lagging behind, as did industrialization in this region of the world. However, this was not the case. The export orientation of the mining industry and its peripheral location in the world economy introduced certain modifications not found in the North Atlantic economies. The vagaries of the mining industry, exacerbated by the severe swings in raw material prices, created conditions which hindered proletarianization and modified the consciousness of the mine workers.
Unemployment Insurance, Trade Unions and the Strange Case of the Israeli Labour Movement
Authors: Gal John
Published: February 2009

The goal of this paper is to investigate the relationship between the labour movement and unemployment insurance (UI). Following a brief overview of the evolution of the approach of labour movements towards UI, the focus shifts to an analysis of a case study of the Israeli labour movement. The study traces the development of the approach of this movement towards UI during the pre-state period and following the establishment of Israel. It indicates that, while the policy adopted by the Israeli labour movement in the pre-state period was similar to that of other labour movements, the motivation differed in that the goals of the Israeli movement were primarily nationalist. In the post-independence period, the labour movement objected to the adoption of UI and prevented the introduction of this programme for two decades. The reasons for this are linked to the values and perceptions of the labour movement leadership and the legacies of policies adopted during the pre-state period.
Life-Long Work or Well-Deserved Leisure in Old Age? Conceptions of Old Age Within the French and German Labour Movements in the Late Nineteenth and Early Twentieth Centuries
Authors: Schniedewind Karen
Published: February 2009

The close connection between old age and retirement and to what extent society accepts work-free retirement in old age emerged as the topical themes we know in France and Germany as late as the 1950s and 1960s. By analysing the relevant discussions in the labour circles of both countries the author examines whether this modern concept of retirement originated in the early phase of the welfare state. The concepts and points of criticism which each of the labour movements developed for old age provision show, by virtue of the different national mental attitudes, that their considerations about old age as a life phase diverged from one another to a great degree. The German labour movement believed that old age pensions were primarily a compensation for the reduction in income on reaching an advanced age, and it thus gave preference to the invalidity pension. In contrast, French society supported the idea of welfare security for the old. Along with criticisms of state social policies, the purpose of providing for the old is at the centre of the essay's analysis, more specifically the contrary forms this discussion took in Germany and France: obliged to work in old age or well-earned retirement.
Worker Resistance and Taylorism in Britain
Authors: Whitston Kevin
Published: February 2009

Worker resistance and employer conservatism in Britain are said to have combined to retard British economic development and frustrate the emergence of modern managerial structures based on Taylorism and/or Fordism. However, the notion of worker resistance is a deeply unsatisfactory one because it fails to distinguish different forms of resistance and their implications for the labour process. And if British employers were slow to abandon older tools and techniques, they nevertheless did so. Worker resistance secured better terms and conditions of employment but was incapable of altering in any fundamental way the new methods of organizing work and managing production.
Mexican State Development Policy and Labor Internationalism, 1945–1958
Authors: Caulfield Norman
Published: February 2009

The Mexican state's drive toward industrialization during World War II and the post-war years required the cooperation of organized labor. Central to this policy was the role played by American trade unions, which cooperated with US government agencies in providing financial and logistical support for Mexican trade unionists who complied with state development policy. The interests of American labor leaders, US policymakers and Mexican modernizing elites converged in an attempt to eradicate radical unionism and promote US hegemony in the western hemisphere. This study builds upon works that treat the earlier activities of US labor in Mexico.
Family, Work and Wages: The Stéphanois Region of France, 1840–1914
Authors: Hanagan Michael
Published: February 2009

Exploring issues of the family wage, this paper examines labour markets, family employment patterns and political conflict in France. Up to now, the debate over the family wage has centred mainly on analysing British trade unions and the development of an ideal of domesticity among the British working classes, more or less taking for granted the declining women's labour force participation rate and the configuration of state/trade union relations prevailing in Great Britain. Shifting the debate across the Channel, scholars such as Laura Frader and Susan Pedersen have suggested that different attitudes to the family wage prevailed. In France, demands for the exclusion of women from industry were extremely rare because women's participation in industry was taken for granted. But a gendered division of labour and ideals of domesticity remained and made themselves felt in both workforce and labour movement.
Comparing the Post-War Germanies: Breadwinner Ideology and Women's Employment in the Divided Nation, 1948–1970
Authors: von Oertzen Christine , Rietzschel Almut
Published: February 2009

In 1989, when Germany became reunified after forty years of separation, no one could overlook the fact that East and West Germany differed greatly with regard to the position of women. The most striking difference of all seemed to lie in the rates of female employment: 91 per cent of all East German women under the age of 60 were counted as being employed, compared to only 55 per cent in West Germany.
Workless Revolutionaries: The Unemployed Movement in Revolutionary Iran
Authors: Bayat Asef
Published: February 2009

This article chronicles the genesis, process and forms of collective protests by the unemployed in Iran immediately following the revolution of 1979. It analyzes the dynamics of jobless mobilization in demanding employment and social protection by exploring its complex relationships with the Islamic government, the opposition forces and the broader revolutionary process. In developing countries, an organized struggle of the unemployed for jobs and protection is extremely rare, notwithstanding high rates of open and concealed joblessness. Family, kinship, patron-client relationships and especially the informal sector provide essential mechanisms for protection and survival; lack of ‘organization generally prevents the emergence of sustained protest movements. I argue that the conjuncture-based articulation of resources and political opportunity underlying the movement set the Iranian case apart. The resources included the post-revolutionary massive and sudden loss of jobs along with the rise of a revolutionary ideology among the jobless.
“Without Any More Law Than Their Own Caprice”: Cotton Textile Workers and the Challenge to Factory Authority During the Mexican Revolution
Authors: Bortz Jeffrey
Published: February 2009

Much current literature argues that the Mexican revolution was not a revolution at all, but rather a series of rebellions that did not fundamentally alter the social order. Similarly, many scholars assert the changes in the Mexican work world during the Mexican revolution were the result of a paternalistic state rather than the product of the actions of workers. This article examines cotton textile workers' relationship to authority in the workplace during the most violent phase of Mexico's revolution, 1910–1921. The results suggest that revolution indeed gripped the country, one that energized the country's still emerging factory proletariat. There is compelling evidence that millhands throughout Mexico continuously and successfully challenged the authority of owners and supervisors, fundamentally altering the social relations of work. It is this “hidden” revolution in the factories that explains changes in labor law, labor organization, and worker power in the immediate post-revolutionary period. The effectiveness of the workers' challenge to authority is what explains: 1) the new regime's need to unionize; 2) the development of pro-labor labor law after the revolution; 3) the power of unions after 1920. In short, workers' challenge to authority during the revolution is what explains the labor outcome of the revolution afterwards.
Macrofaunal community responses to marina-related pollution on the south coast of England and west coast of France
Authors: Callier Myriam D. , Fletcher Robert L. , Thorp Clifford H. , Fichet Denis
Published: February 2009

This study evaluates the influence of man-made activities on the benthic environment at two different marinas: Southsea Marina on the south coast of England, and Minimes Marina on the Atlantic coast of France. We assessed the differences in: (1) sediment percentage organic matter, particle size and heavy metal concentration, using copper (Cu), cadmium (Cd), zinc (Zn) and lead (Pb) as contamination indicators; (2) sediment elutriate toxicity (LC50) using algal (Fucus serratus) bioassay; and (3) benthic community characteristics (number of species, abundance, most contributing species (SIMPER) and biotic index (AMBI)). Canonical correspondence analysis (CCA) was performed to relate the abundance of species to the environmental variables. At both marinas, we observed an increasing gradient of contamination from outside to the innermost sites. At both marinas, the lowest macrofaunal abundance was recorded at the innermost sites and differences in benthic community structure were observed between sites. At Southsea Marina, the cirratulidsTharyx marioniandT. killariensisand the cossuridCossura pygodactylatadominated sites outside, while the opportunistic speciesCapitellides girardidominated the innermost sites. At Minimes Marina, the cirratulidStreblospio shrubsoliiwas abundant outside and at the middle sites but was almost absent at the innermost sites. The biotic index—AMBI—indicated that sediments in the innermost sites were heavily disturbed at Southsea Marina and slightly to moderately disturbed at Minimes Marina. In Southsea, the AMBI was positively correlated to the sediment metal concentrations (Cu, Zn and Cd) and elutriate toxicity (LC50), while in Minimes the AMBI was positively correlated to the % of sediment fine particle and elutriate toxicity (LC50).
Reproductive characteristics ofCalyptogena gallardoi(Bivalvia: Vesicomyidae) from a methane seep area off Concepción, Chile
Authors: Parra Macarena , Sellanes Javier , Dupré Enrique , Krylova Elena
Published: February 2009

Calyptogena gallardoiis a vesicomyid bivalve inhabiting a methane seep area located at a depth of 740–870 m off the Bay of Concepción, Chile. Vesicomyids host chemoautotrophic sulphide-oxidizing endosymbiont bacteria and are always found associated to reducing environments. In this study, the gonadal structure and the gametes produced byC. gallardoiare described. Light microscopy is used to examine serial histological sections of the gonads, and scanning electron microscopy is used to visualize the external morphology of gametes. The gonads of both males and females are organized in ramified tubular acini. In males, mature sperm are stored near genital openings in acini lined with a secretor epithelium that resembles a seminal receptacle. Spermatozoids have bullet-like heads with an average length of 30.3±2.6 μm (mean±1 SD). In females, the mature oocytes are driven toward the genital opening through evacuator conduits lined by ‘paddle’ cilia. The average diameter of oogonias is 11.6±2.5 μm and that of mature oocytes is 273.8±23.1 μm, making the size of the mature oocyte among the largest reported for bivalves. In addition,C. gallardoiis shown to have external sexual dimorphism. Shells of males are significantly smaller and more elongated with sloping postero-dorsal margin compared with shells of females. The data are discussed in the context of available information on reproductive biology of vesicomyids.
Hydrocoryne iemanja(Cnidaria), a new species of Hydrozoa with unusual mode of asexual reproduction
Authors: Morandini André C. , Stampar Sérgio N. , Migotto Alvaro E. , Marques Antonio C.
Published: February 2009

Hydrocoryne iemanjasp. nov. was found in an aquarium, growing on rhodoliths of coralline algae collected on the south-eastern coast of Brazil (20°40′S 40°2′W). The colonies were reared through maturity in the laboratory. Each colony had up to 7 sessile, long and thin monomorphic zooids, very extensible and flexible, arising from a chitinous, hard dark-brown plate with minute spines. Medusae budded from near the basal part of hydrocaulus, and were released in immature condition, acquiring fully developed interradial gonads 5–7 days after release. Asexual reproduction by longitudinal fission was observed on the hydrocaulus of the polyps, both for those in normal condition and those with injuries. Fission started at the oral region, extending aborally, with a new hard plate formed in the basal part of hydrocaulus. When fission reached the new hard plate, the new polyp detached, becoming free and sinking to the bottom, starting a new colony. Detached polyps were morphologically indistinguishable from other polyps, being able to produce medusae. Mother and daughter polyps undertook subsequent fissions. This mode of longitudinal fission is distinct from other modes of longitudinal fission, a process known for a few species of cnidarians. Further studies of this process may shed light on the understanding of the evolutionary pathways in Cnidaria and animals.Hydrocoryne iemanjasp. nov. is distinguishable from its two congeners by the distinct marginal tentacles of the medusae—short and with a median nematocyst knob—an unambiguous character useful even for the identification of newly liberated medusae.
Absolutely non-computable predicates and functions in analysis
Authors: WEIHRAUCH KLAUS , WU YONGCHENG , DING DECHENG
Published: February 2009

In the representation approach (TTE) to computable analysis, the representations of an algebraic or topological structure for which the basic predicates and functions become computable are of particular interest. There are, however, many predicates (like equality of real numbers) and functions that areabsolutely non-computable, that is, not computable for any representation. Many of these results can be deduced from a simple lemma. In this article we prove this lemma for multi-representations and apply it to a number of examples. As applications, we show that various predicates and functions on computable measure spaces are absolutely non-computable. Since all the arguments are topological, we prove that the predicates are not relatively open and the functions are not relatively continuous for any multi-representation.
Phase transition of multivariate polynomial systems
Authors: FUSCO GIORDANO , BACH ERIC
Published: February 2009

A random multivariate polynomial system with more equations than variables is likely to be unsolvable. On the other hand, if there are more variables than equations, the system has at least one solution with high probability. In this paper we study in detail the phase transition between these two regimes, which occurs when the number of equations equals the number of variables. In particular, the limiting probability for no solution is 1/e at the phase transition, over a prime field.

We also study the probability of having exactly s solutions, with s ≥ 1. In particular, the probability of a unique solution is asymptotically 1/e if the number of equations equals the number of variables. The probability decreases very rapidly if the number of equations increases or decreases.

Our motivation is that many cryptographic systems can be expressed as large multivariate polynomial systems (usually quadratic) over a finite field. Since decoding is unique, the solution of the system must also be unique. Knowing the probability of having exactly one solution may help us to understand more about these cryptographic systems. For example, whether attacks should be evaluated by trying them against random systems depends very much on the likelihood of a unique solution.
Aufgaben und Inhalte der Musikwirkungsforschung – eine Übersicht
Authors: Balzer Hans-Ullrich
Published: February 2009

Zusammenfassung. Der Begriff Musikwirkungsforschung beinhaltet drei Aspekte unseres Lebens. Die Musik, die uns umgibt, mit der wir leben, die wir gestalten. Ihre Wirkungen, die wir fühlen, registrieren, wahrnehmen und bewerten. Unsere Aufgabe ist es die Wirkungen der Musik zu erforschen und damit zu erklären. Warum ist gerade in der heutigen Zeit die Erforschung der Wirkung von Musik so wichtig? In der heutigen Zeit scheint die Zeit selbst viel schneller zu verlaufen, als in früheren Jahrzehnten, Jahrhunderten, sucht die Kunst und damit auch die Musik nach neuen Wegen ihrer Darstellung um die schnell wechselnden Ereignisse in der Gesellschaft, die uns umgibt zu interpretieren und auf sie Einfluss zu nehmen. Die rasante Entwicklung der Computertechnik führt zu einer für den Uneingeweihten fast schon nicht mehr nachvollziehbaren Technisierung aller Lebensprozesse. Die Medizin, vor allem die Intensivmedizin, entwickelt immer modernere kompliziertere Apparate aber gleichzeitig steigt der Verbrauch von Psychopharmaka weltweit immer mehr an. Patienten wenden sich von der Gerätemedizin ab und suchen nach neuen Behandlungsmethoden, angelehnt an Naturheilverfahren, altchinesischen und auch musiktherapeutischen Ansätzen. Dass diese Entwicklung auch für den Bereich der Bildung Probleme aufwirft, ist bereits in der Schule und im Arbeitsmarkt erkennbar. Im Jahre 2001 wurde an der Universität Mozarteum Salzburg das Forschungsnetz Mensch und Musik ins Leben gerufen. International kann davon ausgegangen werden, dass sich zum gegenwärtigen Zeitpunkt weltweit ca. 150 Einrichtungen in 22 Ländern mit Musikwirkungsforschung beschäftigen, davon ca. 90 Einrichtungen im europäischen Raum. Der Schwerpunkt der Forschung liegt bisher auf dem Gebiet psychologischer Studien zur Musikwahrnehmung gefolgt von musiktherapeutischen und neurobiologischen Forschungen zur Wirkung von Musik. Seltener vertreten sind Untersuchungen zu biochemischen Fragenstellungen. Darüber hinaus gibt es Forschungen zum Einsatz von Musik als Mittel zur Leistungssteigerung. Annähernd 10 Einrichtungen befassen sich mit mathematischen Methoden zur Integration der verschiedensten Untersuchungsergebnisse. Lediglich 4 Einrichtungen konnten auf dem Gebiet Musikwirkungsforschung im Zusammenhang mit chronobiologischen Ansätzen recherchiert werden. Daneben gibt es einzelne Einrichtungen und Forscher, die sich mit mathematischen Methoden der Musikanalyse beschäftigen ohne jedoch medizinische oder psychologische Forschungsmethoden zu integrieren. Für den Bereich der Kunstwirkungsforschung ist schätzungsweise 1/10 der recherchierten Forschungseinrichtungen aktiv. Um die Musikwirkungsforschung in die Lösung unserer gesellschaftlichen Aufgaben mit einzubeziehen, bedarf es einer Intensivierung der Forschung, einer Qualifizierung der Lehre und einer Aufklärung auf breiter Basis.
Das Ganzkörper-Monochord
Authors: Sandler Hubertus , Tamm Sascha , Klapp Burghard , Bösel Rainer
Published: February 2009

Zusammenfassung. Musiktherapeutischer Literatur zufolge soll durch die Rezeption des Klanges von Monochord bzw. Ganzkörper-Monochord das Erleben veränderter Wachbewusstseinszustände (VWB) induziert werden können. In der vorliegenden Studie wurde untersucht, ob die EEG-Aktivität und das subjektive Erleben während einer Behandlung mit einer Klangliege sich von einem mittels Progressiver Muskelrelaxation induzierten Entspannungszustand unterscheiden. Das Erleben eines VWBs wurde von 31 Probanden während beider Bedingungen quantitativ erfasst. Zusätzlich wurde das subjektive Erleben während der Klangexposition qualitativ erhoben. Während beiden Bedingungen wurde EEG abgeleitet, FFT-anaysiert und die EEG-Leistungsspektren der Alpha- und Theta-Power zwischen den Bedingungen verglichen. Es zeigte sich, dass sich während der Klangexposition bei den meisten Probanden ein bedeutend intensiveres Erleben eines VWBs einstellte. Bei der Subgruppe der Probanden mit intensiv erlebtem VWB konnte vor allem im parietalen Bereich des Gehirns ein Anstieg der EEG-Theta-Aktivität festgestellt werden. Die EEG-Alpha-Aktivität differenzierte nicht zwischen den Bedingungen.
Core‐complex‐related extension of the Aegean lithosphere initiated at the Eocene‐Oligocene transition
Authors: Forster Marnie , Lister Gordon
Published: February 2009

Core‐complex‐related stretching of the Aegean lithosphere was accommodated in part by the South Cyclades Shear Zone (SCSZ), which outcrops on the islands of Ios and Thera, Aegean Sea, Greece. This paper reports new microstructurally focused40Ar/39Ar geochronology that suggests the SCSZ initiated just before the time of the Eocene‐Oligocene transition (at ∼35 Ma). Therefore it is not only Miocene extension that led to the Tethyan metamorphic core complexes exposed in the Cycladic archipelago. It is shown here that pervasive top‐to‐the‐south directed ductile shear took place in the SCSZ for ∼5 Ma during the early Oligocene, followed by initiation of overprinting north‐sense shear zones at the time of the Oligocene‐Miocene transition (at ∼25 Ma). This means that modern (core complex related) extension in the Aegean started much earlier than has been previously recognized and that stretching of the Aegean lithosphere took place in a distinctly episodic fashion, not in a manner that can be described as continuous or progressive. The data also mean that the complementary shear‐sense geometry of the SCSZ and the North Cyclades Shear Zone (NCSZ) cannot be interpreted as crustal‐scale boudinage initiated during crustal extension in Miocene time since the opposing sense shear zones operated at distinctly different times. The paper illustrates the difficulties involved in systematically determining the age of deformation fabrics using40Ar/39Ar geochronology and provides a case study that shows the value of carefully designed step‐heating experiments on microstructurally controlled samples. In samples such as these, from complex metamorphic tectonites, laser fusion, or step‐heating experiments with relatively few steps, would have led to erroneous conclusions.
Stochastic and direct acceleration mechanisms in the Earth's magnetotail
Authors: Perri S. , Greco A. , Zimbardo G.
Published: February 2009

Ion beams with energies of the order of several tens of keV are frequently observed in the Earth's magnetotail. Here we consider two possible acceleration mechanisms, the cross tail electric field Ey and the stochastic acceleration due to the electromagnetic fluctuations present in the magnetotail. Electromagnetic perturbations are generated by random oscillating “clouds” moving in the x − y plane. A test particle simulation has been performed in order to reproduce the interaction between protons and electromagnetic fluctuations and the constant dawn‐dusk electric field, Ey, in the magnetotail current sheet. Protons are accelerated via a stochastic Fermi‐like process and, by varying the features of the electromagnetic fluctuations, the combined effect of Ey and of the moving clouds can explain the typical energy range of ion observations from 20 to 100 keV, and the characteristic acceleration times of several minutes.
FAST observations of downward current regions: Effect of magnetospheric conditions on the parallel potential drop
Authors: Hwang K.‐J. , Lynch K. A. , Newman D. L. , Carlson C. W.
Published: February 2009

The effects of background plasma sheet boundary conditions on the downward current region potential structures are investigated using FAST observations of both ionospheric and plasma sheet populations. Precipitating plasma sheet electrons are observed to partially control the magnitude of the potential drop consistent with theories of charge‐neutrality requirements throughout ionospheric and magnetospheric regions. This leads to a new empirical model of a downward current region (DCR) current‐voltage relation for U‐shaped events. Hot plasma sheet ions are observed to play an important role in reducing the variability of the potential drop, possibly by acting as a sink or buffer for free energy caused by the resulting energetic upward electron beams. The statistical studies of boundary conditions in the auroral downward current region in this and our companion paper show that both ionospheric and magnetospheric conditions appear to regulate the DCR potential structures observed at FAST altitudes. The initiation of downward current region potentials seems to be influenced mainly by low‐altitude ionospheric conditions. Once the U‐shaped potential structure is formed, the effects of the ionospheric influences may be relaxed and modulated by effects from magnetospheric conditions.
Observations of GW/TID oscillations in the F2 layer at low latitude during high and low solar activity, geomagnetic quiet and disturbed periods
Authors: Klausner V. , Fagundes P. R. , Sahai Y. , Wrasse C. M. , Pillat V. G. , Becker‐Guedes F.
Published: February 2009

Ionospheric vertical sounding observations, using a digital ionosonde, are being carried out on a routine basis at Sao Jose dos Campos (23.2°S, 45.9°W; dip latitude 17.6°S, hereafter referred to as SJC), Brazil, located under the southern crest of the equatorial ionization anomaly (EIA), since August 2000. In this paper, we present and discuss the seasonal variation of gravity wave (GW) and traveling ionospheric disturbance (TID) oscillations in the ionospheric F2 layer during high solar activity (HSA, September 2000 to August 2001) and low solar activity (LSA, January 2006 to December 2006) observed at SJC during different levels of geomagnetic activity. The GW/TID signatures in the F2 layer can be seen in the isofrequency lines of virtual height daily variations for six fixed frequencies (3, 4, 5, 6, 7, and 8 MHz) which show quasiperiodic oscillations (crests and valleys). The crests and valleys when seen in close frequencies present a phase difference (i.e., first it is observed at higher frequency then at lower frequency), indicating a downward phase velocity. These quasiperiodic oscillations induced in the virtual heights are divided into three groups as small amplitude (lower than 40 km), medium amplitude (between 40 km and 60 km), and large amplitude (greater than 60 km). The observations show that GWs/TIDs are much more pronounced at F layer heights during HSA than LSA and the large‐amplitude GWs/TIDs are present normally only during HSA.
Storm‐dependent radiation belt electron dynamics
Authors: Tu Weichao , Li Xinlin , Chen Yue , Reeves G. D. , Temerin M.
Published: February 2009

Using recently published electron phase space densities (PSD) as a function of L* (L* is approximately the radial distance in Earth radii at the equator) and time, energization and loss in the Earth's outer electron radiation belt were studied quantitatively and numerically using a radial diffusion model that included finite electron lifetimes and an internal source parameterized as a function of geomagnetic indices. We used PSD data at fixed values of the first and second adiabatic invariants, corresponding to electrons mirroring near the Earth's equator with an energy of ∼2.7 MeV at L* = 4. Model results for the second half of 2002 reproduced the average variations of the radiation belt electron PSD between L* = 2.5 and L* = 6 but with overprediction and underprediction at different times, implying that the same set of parameters cannot be applied to all storms. A detailed analysis of four individual storms showed that while electrons in three storms could be well simulated by energization from either radial diffusion only or internal heating only, incorporating both yielded the best results. For the other storm, an additional source of electrons was required to account for the enhanced PSD. The model results indicated that each storm is best simulated when a combination of radial diffusion and internal heating is used. Different storms required different magnitudes of radial diffusion and internal heating, and the relative contributions of these two acceleration mechanisms varied from storm to storm. A comparison of the results from different runs for the four storms and an analysis of the radial diffusion coefficients further suggest that internal heating contributes more to the enhancement of 2.7 MeV electrons at L* = 4 than radial diffusion.
Southern San Andreas‐San Jacinto fault system slip rates estimated from earthquake cycle models constrained by GPS and interferometric synthetic aperture radar observations
Authors: Lundgren Paul , Hetland Eric A. , Liu Zhen , Fielding Eric J.
Published: February 2009

We use ground geodetic and interferometric synthetic aperture radar satellite observations across the southern San Andreas (SAF)‐San Jacinto (SJF) fault systems to constrain their slip rates and the viscosity structure of the lower crust and upper mantle on the basis of periodic earthquake cycle, Maxwell viscoelastic, finite element models. Key questions for this system are the SAF and SJF slip rates, the slip partitioning between the two main branches of the SJF, and the dip of the SAF. The best‐fitting models generally have a high‐viscosity lower crust (η = 1021 Pa s) overlying a lower‐viscosity upper mantle (η = 1019 Pa s). We find considerable trade‐offs between the relative time into the current earthquake cycle of the San Jacinto fault and the upper mantle viscosity. With reasonable assumptions for the relative time in the earthquake cycle, the partition of slip is fairly robust at around 24–26 mm/a for the San Jacinto fault system and 16–18 mm/a for the San Andreas fault. Models for two subprofiles across the SAF‐SJF systems suggest that slip may transfer from the western (Coyote Creek) branch to the eastern (Clark‐Superstition hills) branch of the SJF from NW to SE. Across the entire system our best‐fitting model gives slip rates of 2 ± 3, 12 ± 9, 12 ± 9, and 17 ± 3 mm/a for the Elsinore, Coyote Creek, Clark, and San Andreas faults, respectively, where the large uncertainties in the slip rates for the SJF branches reflect the large uncertainty in the slip rate partitioning within the SJF system.
On the accuracy of noble gas recharge temperatures as a paleoclimate proxy
Authors: Cey Bradley D.
Published: February 2009

Dissolved noble gases in groundwater are an important terrestrial temperature proxy for the last glacial maximum (LGM). Noble gas temperatures (NGT) provide a record of long‐term mean water table temperature (WTT) during groundwater recharge. For NGT to accurately represent surface air temperatures (SAT), the difference between mean annual air temperature (MAAT) and WTT must be known through time. Many paleoclimate studies reference NGT without articulating the potential difference between NGT and air temperature. Recognizing the array of climatic changes that have occurred since the LGM, it is possible some of these changes have altered the relationship between WTT and MAAT in groundwater recharge zones. The coupling of WTT and MAAT was evaluated in numerical modeling experiments that examined WTT sensitivity to changes in (1) precipitation amount, (2) water table depth, and (3) air temperature. Moderate changes in precipitation amount (±20%) and water table depth (1–2 m) caused WTT‐MAAT decoupling of ∼0.2°C. Varying air temperature, either MAAT or annual amplitude, changed the duration of snow cover which caused seasonal decoupling of WTT from SAT. Assuming SAT was actually 5–7°C cooler at the LGM than at present, these modeling experiments suggest that errors associated with WTT‐MAAT decoupling at snow‐free sites are insignificant given the precision of NGT. However, results indicate that WTT‐MAAT decoupling could cause an underestimation of the actual SAT change by ∼1.4°C at sites having seasonal snow cover.
Eddy covariance measurements of surface energy budget and evaporation in a cool season over southern open water in Mississippi
Authors: Liu Heping , Zhang Yu , Liu Shuhua , Jiang Haimei , Sheng Li , Williams Quinton L.
Published: February 2009

Eddy covariance measurements of sensible (H) and latent (LE) heat fluxes were made over a large southern open water surface of Ross Barnett Reservoir (the Reservoir hereafter) in Mississippi during the cool season with frequent incursions of cold fronts from 1 September 2007 to 31 January 2008. The eddy covariance tower was located in the middle of the main body of the Reservoir with the tower fetches exceeding 2.0 km in all directions. The Reservoir was ice‐free in winter and the water temperatures always decreased with depth. Over the entire cool season, the averaged water surface temperatures were 1.8°C higher than the overlying air (i.e., positive temperature gradients that led to thermally convective conditions) and the averaged vapor pressure near the water surface was 0.8 kPa greater than the overlying air (i.e., positive vapor pressure gradients), though occasionally negative gradients for temperature and vapor pressure were also observed for short periods. On average, the wind speeds were considerably large (3.9 m s−1) to maintain adequate turbulent mixing mechanically. As a consequence of the combined effect of thermally and mechanically generated turbulent mixing, consistently positive H (with a mean H of 20.0 W m−2) and LE (with a mean LE of 80.0 W m−2) occurred during the entire season. These continuous energy losses via H and LE resulted in release of a large amount of energy stored in the water to the atmosphere. The mean Bowen ratio was low for this open water surface (i.e., 0.3), suggesting that most of the energy released from the water fueled evaporation rather than sensible heating of the atmosphere. Nighttime evaporative water losses were substantial, contributing to 45% of the total evaporative water loss in this cool season. Frequent incursions of cold fronts with windy, cold, and dry air masses significantly promoted turbulent exchanges of sensible and latent heat through enhanced turbulent mixing thermally and mechanically, leading to large H and LE events. Daily H and LE (i.e., evaporation) during the passages of cold fronts were on average 2.7 and 7.3 times those in nonevent days, respectively. Given the fact that large H and LE events occurred 26% of the time for our site, these cold front events caused an increase in the seasonal H by 42% and LE by 157%. Therefore changes in frequency, intensity, and duration of synoptic weather events, particularly the incursions of cold fronts, have significant impacts on the surface energy budget and evaporation over water at this site.
Spatial and seasonal variability of raindrop size distributions in southeast India
Authors: Radhakrishna B. , Rao T. Narayana , Rao D. Narayana , Rao N. Prabhakara , Nakamura K. , Sharma Ashok Kumar
Published: February 2009

Long‐term measurements of raindrop size distribution (DSD) made with the Joss‐Waldvogel disdrometers at two sites (Gadanki, an inland station, and Cuddalore, a coastal station) in southeast India are utilized to study the seasonal and spatial variations of DSD. The stratified DSD data (based on rain rate R) show significant seasonal variation at both sites. Smaller‐drop concentration is higher in the northeast monsoon (NEM) than in the southwest monsoon (SWM) for the same R. Paucity of smaller drops in SWM increases the mass weighted mean diameter (Dm) considerably. The seasonal differences are pronounced at Gadanki. The seasonal differences are found to be a regular feature at these locations as they are observed in all the years. The DSD has also shown clear diurnal variation with large Dm values in evening hours. The possible causative mechanisms for the observed spatial and seasonal DSD differences are investigated in detail using satellite and radiosonde observations. In particular, the research attempted to address the following question: Are the observed seasonal differences in DSD arising at the cloud formation level or related to the microphysical processes occurring in the evolution of DSD. The low‐level wind pattern and cloud effective radius and Dm distributions in these seasons reveal that the cloud systems in SWM and NEM are continental and maritime, respectively, in nature. However, the microphysical and dynamical processes related to evaporation and convection also seem to play an important role in modifying the DSD. These processes are found predominantly in SWM and are, primarily, responsible for the changes in DSD during their evolution.
Performance of shape-varying magnetic tunneling junction for high-speed magnetic random access memory cells
Authors: Honjo H. , Fukami S. , Nebashi R. , Suzuki T. , Ishiwata N. , Miura S. , Sugibayashi T.
Published: February 2009

We have developed a shape-varying magnetic tunneling junction (MTJ) (SVM) which has a high MR ratio and low write current for use in high-speed magnetic random access memory (MRAM) cells. Combining NiFe that has low anisotropy to CoFeB which has high anisotropy through the nonmagnetic layer by interlayer exchange coupling (synthetic ferromagnetic coupling free layer: SFF), the anisotropy of SFF was reduced much more than that of CoFeB, and the MR ratio was improved much more than that of NiFe. The switching magnetic field (Hsw) of SFF was reduced as the thickness of NiFe increased. The Hsw of SFF for 0.24×0.48 μm2 MTJ was 30 Oe when the thickness of CoFeB was 1.5 nm and that of NiFe was 3.0 nm. Furthermore Hsw was reduced to 18 Oe by varying the shape of the MTJ of NiFe to 0.48×0.48 μm2; the shape of the MTJ of CoFeB was not changed (0.24×0.48 μm2). Combining the SVM and a write-line-inserted structure, we obtained a write current of 0.9 mA and an MR ratio of 140%. The Hsw was 40 Oe and its thermal stability factor was 82. These properties are sufficient for operating MRAMs over 500 MHz.
Reduction in switching current using a low-saturation magnetization Co–Fe–(Cr, V)–B free layer in MgO-based magnetic tunnel junctions
Authors: Kubota Hitoshi , Fukushima Akio , Yakushiji Kay , Yakata Satoshi , Yuasa Shinji , Ando Koji , Ogane Mikihiko , Ando Yasuo , Miyazaki Terunobu
Published: February 2009

Magnetic properties, magnetoresistance (MR), and spin-transfer switching of magnetic tunnel junctions having a structure of Co60Fe20B20 3 nm/MgO 1 nm/(Co75Fe25)80−XCr(V)XB20 2 nm (X=0–25) were investigated. Magnetization of the (Co–Fe)–(Cr, V)–B free layer decreased from 1.2 T before substitution to 0.6 T at Cr of 10% (0.8 T at V of 10%). The MR ratio and a resistance-area product (RA) before substitution were, respectively, about 130% and about 2 Ω μm2. The MR ratio decreased to 80% at Cr of 10% and 40% at V of 10%. The RA values were almost independent of the composition. The intrinsic switching current density (Jc0) decreased from 15 to 8 MA/cm2 at Cr of 10% and 12 MA/cm2 for V of 10%. Upon the further increase in Cr and V, stable switching was difficult to observe. In summary, Jc0 decreased to half in the case of Cr, but the effect was small for V.
Low-energy photoelectron imaging spectroscopy of nitromethane anions: Electron affinity, vibrational features, anisotropies, and the dipole-bound state
Authors: Adams Christopher L. , Schneider Holger , Ervin Kent M. , Weber J. Mathias
Published: February 2009

We present low-energy velocity map photoelectron imaging results for nitromethane anions. The photoelectron spectrum is interpreted with the aid of ab initio theory and Franck–Condon factor calculations. We obtain a new value for the adiabatic electron affinity of nitromethane of (172±6) meV and observe the dipole-bound state of nitromethane. The photoelectron angular distributions of the observed features are discussed in the context of threshold laws for photodetachment.
A study of the pair and triplet structures of the quantum hard-sphere Yukawa fluid
Authors: Sesé Luis M.
Published: February 2009

The pair and triplet structures of the quantum hard-sphere Yukawa fluid, evaluated for equilateral and isosceles correlations in both the r and the k spaces for a range of conditions and with a particular focus on a region where the onset of increasing number fluctuations takes place (for densities 0.4≤ρN∗≤0.5, along the isotherm λB∗=0.6), are computed via path-integral Monte Carlo simulations in the canonical ensemble and an appropriate Ornstein–Zernike framework. For a given type of correlation (instantaneous, continuous linear response, and centroids), the structural results in r space display how the correlation functions approach each other with decreasing densities as a result of the increasing fluctuations. An attempt at obtaining improved isothermal compressibilities by using a simplified grand-canonical correction to the canonical pair radial functions is also discussed in detail. The results for triplets in k space are based on triplet direct correlation function calculations and are restricted to the higher-density region of the interval studied. Complementary results report an assessment of the performances of the Kirkwood superposition and the Jackson–Feenberg convolution. Comparisons with results also obtained in this work for the bare quantum and the classical hard-sphere fluids are made, allowing one to draw conclusions on the interplay between the inclusion of Yukawa attractions and the quantum diffraction effects in hard-sphere fluids.
Power grid vulnerability: A complex network approach
Authors: Arianos S. , Bompard E. , Carbone A. , Xue F.
Published: February 2009

Power grids exhibit patterns of reaction to outages similar to complex networks. Blackout sequences follow power laws, as complex systems operating near a critical point. Here, the tolerance of electric power grids to both accidental and malicious outages is analyzed in the framework of complex network theory. In particular, the quantity known as efficiency is modified by introducing a new concept of distance between nodes. As a result, a new parameter called net-ability is proposed to evaluate the performance of power grids. A comparison between efficiency and net-ability is provided by estimating the vulnerability of sample networks, in terms of both the metrics.
Photon coupling theory for plasmas with strong Compton scattering: Four temperature theory
Authors: Molvig Kim , Alme Marv , Webster Robert , Galloway Conner
Published: February 2009

When an equimolar mixture of deuterium (D) and tritium (T) at high density undergoes fusion burn, the system becomes extremely nonequilibrium. The ion temperature rises much higher than the electron temperature which, in turn, is much higher than the radiation temperature. Accurately simulating this nonequilibrium burn process has previously required a multigroup representation of the radiation field. Although simulating this D–T burn with a simple three temperature model (3T) also results in significant departures from thermal equilibrium, the ion and electron temperature histories from the 3T simulations are much lower than from the multigroup simulations. In this paper, a theory that overcomes the deficiencies of the 3T model in simulating burn of high density D–T is developed. The primary deficiency of the 3T model for this physical system is with the treatment of the Compton scattering energy exchange. The theory here developed culminates in a four temperature model (4T) which describes the radiation field with two temperatures. These are TR, which is the standard radiation temperature of the 3T model (proportional to the fourth root of the radiation energy density), and Tp, which is the true thermodynamic temperature of the photon distribution. This 4T theory gives excellent agreement with the multigroup model for the nonequilibrium burn of D–T. Further, the 4T model transitions smoothly to the 3T model when this is appropriate. Thus the kinetic theory derivation of the 4T model also provides a solid theoretical foundation for the 3T model. Extensions of the theory to inhomogeneous systems are under development to allow treatment of geometries where the computational efficiency of the 4T approach can convey a sizable advantage. There appear to be at least two important applications where the model can be applied. One is for inertial confinement fusion capsules that are optically thick and utilize volume ignition. The second application involves astrophysical accretion disks in the high temperature regime that also exhibit matter heating radiation, albeit without a fusion energy source. A reduced complexity radiation model with the associated reduced computer resource requirements has the potential to facilitate high resolution two dimensional and three dimensional simulations of these astrophysical objects.
Fisher and Jensen–Shannon divergences: Quantitative comparisons among distributions. Application to position and momentum atomic densities
Authors: Antolín J. , Angulo J. C. , López-Rosa S.
Published: February 2009

The Fisher divergence (FD) and Jensen–Shannon divergence (JSD) are used in this work with the aim of providing quantitative measures of the discrepancies between two arbitrary D-dimensional distribution functions, the FD being of local character and the JSD of global one. In doing so, the concepts of Fisher information and Shannon entropy associated to a distribution are the essential quantities for building up these comparative functionals. This kind of relative measures are here applied to the study of the one-particle densities in both conjugated spaces (position and momentum) of neutral atoms, discussing the results as compared to those provided by other previous functional measures. It is clearly shown how these divergences provide relevant information on the atomic shell structure, up to a level which depends on the considered space and measure.
Observation of the parametric-modulational instability between the drift-wave fluctuation and azimuthally symmetric sheared radial electric field oscillation in a cylindrical laboratory plasma
Authors: Nagashima Yoshihiko , Itoh Sanae-I. , Shinohara Shunjiro , Fukao Masayuki , Fujisawa Akihide , Terasaka Kenichiro , Kawai Yoshinobu , Tynan George R. , Diamond Patrick H. , Yagi Masatoshi , Inagaki Shigeru , Yamada Takuma , Itoh Kimitaka
Published: February 2009

Observation of the parametric-modulational interaction between the drift-wave fluctuation (7–8 kHz) and azimuthally symmetric sheared radial electric field structure (∼0.4 kHz) in a cylindrical laboratory plasma is presented. Oscillation of the sheared radial electric field is synchronized at modulations of the radial wave number and Reynolds stress per mass density of the drift-wave spectrum. Bispectral analysis at the location where the sheared radial electric field has finite radial wave numbers shows that nonlinear energy transfers from the drift wave to the sheared radial electric field occur. Nonlocal energy transfers of fluctuations via “channel of the azimuthally symmetric sheared radial electric field” in spectral space as well as real space are discovered.