Local convergence of quasi-Newton methods under metric regularity

We consider quasi-Newton methods for generalized equations in Banach spaces under metric regularity and give a sufficient condition for q-linear convergence. Then we show that the well-known Broyden update satisfies this sufficient condition in Hilbert spaces. We also establish various modes of q-superlinear convergence of the Broyden update under strong metric subregularity, metric regularity and strong metric regularity. In particular, we show that the Broyden update applied to a generalized equation in Hilbert spaces satisfies the Dennis–Moré condition for q-superlinear convergence. Simple numerical examples illustrate the results.

Evidence for non-conservative current-induced forces in the breaking of Au and Pt atomic chains

This experimental work aims at probing current-induced forces at the atomic scale. Specifically it addresses predictions in recent work regarding the appearance of run-away modes as a result of a combined effect of the non-conservative wind force and a ‘Berry force’. The systems we consider here are atomic chains of Au and Pt atoms, for which we investigate the distribution of break down voltage values. We observe two distinct modes of breaking for Au atomic chains. The breaking at high voltage appears to behave as expected for regular break down by thermal excitation due to Joule heating. However, there is a low-voltage breaking mode that has characteristics expected for the mechanism of current-induced forces. Although a full comparison would require more detailed information on the individual atomic configurations, the systems we consider are very similar to those considered in recent model calculations and the comparison between experiment and theory is very encouraging for the interpretation we propose.

Aristotelian predicables, universality and realism: the logic of comparison in topics as denying the view that Aristotle was a realist

Aristotle is reportedly held to have been a Moderate Realist in that he would maintain that a concept derives from an act of grasping a mind-independent universal object that exists somehow inside of the many different things which the concept is predicated of. As far as a universal is independent of mind, it would stand for the proper object of a concept that subsumes a given number of things as its own instantiations. But we claim that Aristotle rejected such a view and instead did perceive and comprehend universality as a feature of thought rather than as a feature of reality in its own right. As showed in the chapters of Topics regarding the so-called logic of comparison (with the support of Albert the Great’s commentary), each predicate can be more or less consistent with the attribute of the subject of which it may be predicated. Both essential and accidental attributes assume a definite degree of being related to the degree of belonging to substance. Unlike particular things, the universality of a concept is to be understood always in comparison with another concept according to a hierarchy of predicates in terms of universality degree arranged by comparative terms such as ‘more’, ‘less’, and ‘likewise’. What is really mind-independent are the truth conditions which make a universal true when exclusively referring to a set of things identically meant by the same predicate whose universality is given by the place occupied in the hierarchy of predicates.

The Ascent of EU Environmental Policy: A Case for Unintended Consequences. EDAP 1/2015

This paper aims to explore the issue of unintended consequences as the key underlying theme that explains the incremental integration of policies in the EU, with a particular focus on the issue of environmental protection. The theoretical background of the present research is provided by two of the main schools of thought that, in different historical contexts, have theorized unintended consequences as a relevant interpretative/analytical tool for European integration, namely neo-functionalism and neo-institutionalism. The paper focuses on three distinctive moments of the EU environmental policy: the first steps in the 1970s, the change of regulatory paradigm during the 1990s, and the EU leadership role in global environmental policy. The main argument is that while neo-functionalism can give a convincing account of the initial phases of EU environmental policy, neo-institutionalism offers a persuasive framework to understand the consolidation phases of the policy.

The Legal Construction of Membership: Nationality Law in Germany and the United States. CES Germany & Europe Working Papers No. 00.5, 2000

The argument of this paper is that several empirical puzzles in the citizenship literature are rooted in the failure to distinguish between the mainly legal concept of nationality and the broader, political concept of citizenship. Using this distinction, the paper analysis the evolution of German and American nationality laws over the last 200 years. The historical development of both legal structures shows strong communalities. With the emergence of the modern system of nation states, the attribution of nationality to newborn children is ascribed either via the principle of descent or place of birth. With regard to the naturalization of adults, there is an increasing ethnization of law, which means that the increasing complexities of naturalization criteria are more and more structured along ethnic ideas. Although every nation building process shows some elements of ethnic self-description, it is difficult to use the legal principles of ius sanguinis and ius soli as indicators of ethnic or non-ethnic modes of community building.

Innovation and Development in the Age of Climate Change Adaptation: Open or Closed?

Change Adaptation: Open or Closed? Paper read at the Second African International Economic Law Network Conference, 7-8 March 2013, Wits School of Law, Johannesburg, South Africa. In a time of rapid convergence of technologies, goods, services, hardware, software, the traditional classifications that informed past treaties fail to remove legal uncertainty, or advance welfare and innovation. As a result, we turn our attention to the role and needs of the public domain at the interface of existing intellectual property rights and new modes of creation, production and distribution of goods and services. The concept of open culture would have it that knowledge should be spread freely and its growth should come from further developing existing works on the basis of sharing and collaboration without the shackles of intellectual property. Intellectual property clauses find their way into regional, multilateral, bilateral and free trade agreements more often than not, and can cause public discontent and incite unrest. Many of these intellectual property clauses raise the bar on protection beyond the clauses found in the WTO Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS). In this paper we address the question of the protection and development of the public domain in service of open innovation in accord with Article 15 of the International Covenant on Economic, Social and Cultural Rights (ICESCR) in light of the Objectives (Article 7) and Principles (Article 8) set forth in TRIPS. Once areas of divergence and reinforcement between the intellectual property regime and human rights have been discussed, we will enter into options that allow for innovation and prosperity in the global south. We then conclude by discussing possible policy developments.

Long-term Responses of Mountain Ecosystems to Environmental Changes: Resilience, Adjustment, and Vulnerability

The steep environmental gradients of mountain ecosystems over short distances reflect large gradients of several climatic parameters and hence provide excellent possibilities for ecological research on the effects of environmental change. To gain a better understanding of the dynamics of abiotic and biotic parameters of mountain ecosystems, long-term records are required since permanent plots in mountain regions cover in the best case about 50 - 70 years. In order to extend investigations of ecological dynamics beyond these temporal limitations of permanent plots, paleoecological approaches can be used if the sampling resolution can be adapted to ecological research questions, e.g. a sample every 10 years. Paleoecological studies in mountain ecosystems can provide new ecological insights through the combination of different spatial and temporal scales. [f we thus improve our understanding of processes across both steep environmental gradients and different time scales, we may be able to better estimate ecosystem responses to current and future environmental change (Ammann et al. 1993; Lotter et al. 1997). The complexity of ecological interactions in mountain regions forces us to concentrate on a number of sub-systems - without losing sight of the wider context. Here, we summarize a few case studies on the effects of Holocene climate change and disturbance on the vegetation of the Western Alps. To categorize the main response modes of vegetation to climatic change and disturbance in the Alps we use three classes of ecological behaviour: "resilience", "adjustment", and "vulnerability", We assume a resilient (or elastic) behaviour if vegetation is able to recover to its former state, regaining important ecosystem characteristics, such as floristic composition, biodiversity, species abundances, and biomass (e.g. Küttel 1990; Aber and Melillo 199 1). Conversely, vegetation displacements may occur in response to climatic change and/or disturbance. In some cases, this may culminate in irreversible large-scale processes such as species and/or community extinctions. Such drastic developments indicate high ecosystem vulnerability (or inelasticity or instability, for detailed definitions see Küttel 1990; Aber and Melillo 199 1) to climatic change and/or disturbance. In this sense, the "vulnerability" (or instability) of an ecosystem is expressed by the degree of failure to recover to the original state before disturbance and/or climatic change. Between these two extremes (resilience vs. vulnerability), ecosystem adjustments to climatic change and/or disturbance may occur, including the appearance of new and/or the disappearance of old species. The term "adjustment" is hence used to indicate the response of vegetational communities, which adapted to new environmental conditions without losing their main character. For forest ecosystems, we assume vegetational adjustments (rather than vulnerability) if the dominant (or co-dominant) tree species are not outnumbered or replaced by formerly unimportant plant species or new invaders. Adaptation as a genetic process is not discussed here and will require additional pbylogeographical studies (that incorporate the analysis of ancient DNA) in order to fully understand the distributions of ecotypes.

Global compilation of chlorophyll fluorescence profiles from several data bases, and from published and unpublished individual sources

The present data set includes 268,127 vertical in situ fluorescence profiles obtained from several available online databases and from published and unpublished individual sources. Metadata about each profiles are given in the file provided here in further details. The majority of profiles comes from the National Oceanographic Data Center (NODC) and the fluorescence profiles acquired by Bio-Argo floats available on the Oceanographic Autonomous Observations (OAO) platform (63.7% and 12.5% respectively). Different modes of acquisition were used to collect the data presented in this study: (1) CTD profiles are acquired using a fluorometer mounted on a CTD-rosette; (2) OSD (Ocean Station Data) profiles are derived from water samples and are defined as low resolution profiles; (3) the UOR (Undulating Oceanographic Recorder) profiles are acquired by a equipped with a fluorometer and towed by a research vessel; (4) PA profiles are acquired by autonomous platforms (here profiling floats or elephant seals equipped with a fluorometer). Data acquired from gliders are not included in the compilation.

Sedimentological, geochemical, micropaleontological and rock magnetic proxies of sediment core GeoB6211-2

Surface currents and sediment distribution of the SE South American upper continental margin are under influence of the South American Monsoon System (SAMS) and the Southern Westerly Wind Belt (SWWB). Both climatic systems determine the meridional position of the Subtropical Shelf Front (STSF) and probably also of the Brazil-Malvinas Confluence (BMC). We reconstruct the changing impact of the SAMS and the SWWB on sediment composition at the upper Rio Grande Cone off southern Brazil during the last 14 cal kyr combining sedimentological, geochemical, micropaleontological and rock magnetic proxies of marine sediment core GeoB 6211-2. Sharp reciprocal changes in ferri- and paramagnetic mineral content and prominent grain-size shifts give strong clues to systematic source changes and transport modes of these mostly terrigenous sediments. Our interpretations support the assumption that the SAMS over SE South America was weaker than today during most of the Late Glacial and entire Early Holocene, while the SWWB was contracted to more southern latitudes, resembling modern austral summer-like conditions. In consequence, the STSF and the BMC were driven to more southern positions than today's, favoring the deposition of Fe-rich but weakly magnetic La Plata River silts at the Rio Grande Cone. During the Mid Holocene, the northern boundary of the SWWB migrated northward, while the STSF reached its northernmost position of the last 14 cal kyr and the BMC most likely arrived at its modern position. This shift enabled the transport of Antarctic diatoms and more strongly magnetic Argentinean shelf sands to the Rio Grande Cone, while sediment contributions from the La Plata River became less important. During the Late Holocene, the modern El Niño Southern Oscillation set in and the SAMS and the austral tradewinds intensified, causing a southward shift of the STSF to its modern position. This reinforced a significant deposition of La Plata River silts at the Rio Grande Cone. These higher magnetic silts with intermediate Fe contents mirror the modern more humid terrestrial climatic conditions over SE South America.

(Table 1) Age determination of western North Atlantic sediment cores

Foraminiferal abundance, 14C ventilation ages, and stable isotope ratios in cores from high deposition rate locations in the western subtropical North Atlantic are used to infer changes in ocean and climate during the Younger Dryas (YD) and Last Glacial Maximum (LGM). The d18O of the surface dwelling planktonic foram Globigerinoides ruber records the present-day decrease in surface temperature (SST) of ~4°C from Gulf Stream waters to the northeastern Bermuda Rise. If during the LGM the modern d18O/salinity relationship was maintained, this SST contrast was reduced to 2°C. With LGM to interglacial d18O changes of at least 2.2 per mil, SSTs in the western subtropical gyre may have been as much as 5°C colder. Above ~2.3 km, glacial d13C was higher than today, consistent with nutrient-depleted (younger) bottom waters, as identified previously. Below that, d13C decreased continually to -0.5 per mil, about equal to the lowest LGM d13C in the North Pacific Ocean. Seven pairs of benthic and planktonic foraminiferal 14C dates from cores >2.5 km deep differ by 1100 ± 340 years, with a maximum apparent ventilation age of ~1500 years at 4250 m and at ~4700 m. Apparent ventilation ages are presently unavailable for the LGM < 2.5 km because of problems with reworking on the continental slope when sea level was low. Because LGM d13C is about the same in the deep North Atlantic and the deep North Pacific, and because the oldest apparent ventilation ages in the LGM North Atlantic are the same as the North Pacific today, it is possible that the same water mass, probably of southern origin, flowed deep within each basin during the LGM. Very early in the YD, dated here at 11.25 ± 0.25 (n = 10) conventional 14C kyr BP (equal to 12.9 calendar kyr BP), apparent ventilation ages <2.3 km water depth were about the same as North Atlantic Deep Water today. Below ~2.3 km, four YD pairs average 1030 ± 400 years. The oldest apparent ventilation age for the YD is 1600 years at 4250 m. This strong contrast in ventilation, which indicates a front between water masses of very different origin, is similar to glacial profiles of nutrient-like proxies. This suggests that the LGM and YD modes of ocean circulation were the same.

Mineralogy of some Australian desert samples (Table 3)

The relative amounts of chlorite, montmorillonite, kaolinite and illite in the less than 2 micron size fraction of pelagic sediments are related to the sources and transport paths of solid phases from the continents to the oceans and to injections of volcanic materials to the marine environment. Three modes of entry of solid phases from the lands to the seas are considered: by glaciers, by rivers and by atmospheric winds. The compositions of the clay size fraction are also related to rates of accumulation of the non-biogenous phases.