Nonlinear Relaxation in Population Dynamics

We analyze the nonlinear relaxation of a complex ecosystem composed of many interacting species. The ecological system is described by generalized Lotka-Volterra equations with a multiplicative noise. The transient dynamics is studied in the framework of the mean field theory and with random interaction between the species. We focus on the statistical properties of the asymptotic behaviour of the time integral of the i-th population and on the distribution of the population and of the local field.Comment: 11 pages, 4 figures, in press in Int. Journal of Fractals (2001

Women’s march on London: The importance of sister marches

Ali Cirone, LSE Fellow in Political Economy in the Department of Government, reflects on the Women’s March on London which took place on the 21 January 2017

Choose your own adventure: my time as a capstone supervisor

In essence, MPA Capstone projects match a group second-year students to a client organisation, with the goal of producing an analytically rigorous and innovative report on a real-world policy issue. Over the course of the year, students are expected to apply the empirical and public policy skills learned in the MPA core curriculum, as well as utilise the wealth of advisory and academic resources the LSE has to offer

Magnetic and Newtonian noises in Advanced Virgo: evaluation and mitigation strategies

In the present study, I table the first detailed estimation of the magnetic noise contribution to the Advanced Virgo sensitivity to gravitational waves. I tackle the topic by performing experimental assessments and numerical finite element simulations, all accompanied by careful data analysis. Results suggest that the magnetic noise impact for Advanced Virgo is not dramatic, but it will eventually be a considerable issue once the detector will approach its final design. In anticipation of that, I propose a mitigation strategy based on passive magnetic field shielding. In the second part, I deal with seismic newtonian noise, focusing on two crucial aspects involving the noise cancellation pipeline. These are the choice of the subtraction filter and the optimization of the seismic sensor array placement. The former issue required the definition of a machine learning algorithm based on deep neural networks, and its fine tuning. Results give some indication of good performances compared to the standard Wiener filter approach. The problem of the sensors deployment is instead addressed with the finite element analysis of the actual Virgo infrastructure and underground soil layers surrounding the test masses

Blockchain and the General Data Protection Regulation: an irreconcilable regulatory approach?

A blockchain is a class of technology that allows the creation and management of different forms of decentralised and distributed digital ledgers where data are stored, chronologically recorded, transferred and finally shared between the ‘nodes’ participating in a peer-to-peer network. These features prima facie clash with the GDPR that informs the EU data protection legislation and is based on a centralised representation of the reality in which data are processed, collected, and recorded in a database controlled by identified subjects. The underpinning idea of this article is diametrically opposed to the one which considers the technology not GDPR-compliant by default. First, the author argues that the points of tension can be mitigated by technical and/or governance methods, thus acting at both application and infrastructure level. In essence, a case-by-case analysis is the only feasible option to assess the compliance between the regulation and the technology. Second, a further and closer look at blockchain’s underlying concepts reveals how both the GDPR and the blockchain have the same purposes but different approaches. More interestingly, the article suggests that the blockchain could be seen as a Privacy Enhancing Technology (PET), which might help data subjects gain more control over their personal data and hence support one of the GDPR’s purposes (recital 7)

Provenance Tracing of Glacial Sediment from the Foundation, Academy, and Recovery Ice Streams, Weddell Sea, Antarctica

This project seeks to advance our understanding of Antarctic Ice Sheet dynamics and to gain insight into the bedrock composition beneath the Antarctic Ice Sheet by “fingerprinting” ice streams that drain into the Ronne-Filchner Ice Shelf. The Ronne- Filchner Ice Shelf is the second largest ice shelf in Antarctica and receives ice drained from both the West and East Antarctic Ice Sheets through a series of ice streams. In response to global warming, this sector has the potential to contribute dramatically to sea level rise, especially from the Recovery Catchment. Till samples were collected from lateral moraines adjacent to the Foundation, Academy, and Recovery ice streams, all located within the Weddell Sea sector, during a December 2014 field season. Extensive analyses of sieved fine fraction (\u3c 63 pm) show that all three ice streams have major element profiles that are consistent with the upper continental crust, though with Na and Ca depletion. Al/Ti and Fe/Ti ratios are also consistent with upper continental crust for all three ice streams. Recovery Ice Stream is the only one of the three ice streams to contain Mn- bearing minerals, including psilomelane and hausmannite. Foundation Ice Stream is the only stream containing V- bearing titanomagnetite. The Foundation Ice Stream also contains the most ilmenite. Academy Glacier till exhibits the most alteration textures in Fe-oxides (63%), and Recovery exhibits the most homogeneous Fe-oxide grains (24%). Through developing these geochemical and mineral signatures, this project will allow researchers to develop proxy records for ice stream activity in marine sedimentary records and better understand which ice streams may be the most vulnerable to ice loss as a response to global warming

A Push for Historical Thinking in Elementary History Instruction

While there is research in support of historical thinking in the elementary curriculum, the results vary and this raises the question, how capable are elementary students in engaging in historical thinking? I plan to answer this question by looking at examples of historical thinking in elementary students through their experiences with a unit plan I develop with a central focus on historical inquiry. My goal is to develop a 4-day unit plan for 4th graders on Westward 4 Expansion using the MA Curriculum Frameworks for 4th grade content and NCSS historical thinking skills. I will garner feedback from Worcester area teachers to support the revision of my unit. I will then teach my lessons with elementary students to learn how effective the lessons were in supporting the development of historical thinking in elementary students. There is currently a lack of historical thinking skills being taught in elementary curriculum. This study is important because students may be capable of more critical thinking skills than is typically expected. Due to the necessity of these skills, the earlier students can learn the more successful they will be making claims, recognizing historical perspective, and deeply inquiring into whose story is told in a history and whose is missing