Persistent Topology of Syntax

We study the persistent homology of the data set of syntactic parameters of the world languages. We show that, while homology generators behave erratically over the whole data set, non-trivial persistent homology appears when one restricts to specific language families. Different families exhibit different persistent homology. We focus on the cases of the Indo-European and the Niger-Congo families, for which we compare persistent homology over different cluster filtering values. We investigate the possible significance, in historical linguistic terms, of the presence of persistent generators of the first homology. In particular, we show that the persistent first homology generator we find in the Indo-European family is not due (as one might guess) to the Anglo-Norman bridge in the Indo-European phylogenetic network, but is related to the position of Ancient Greek and the Hellenic branch within the network.Comment: 15 pages, 25 jpg figure

Essays in Health Economics

This thesis consists of three health economics papers, two studying the effectiveness of policy interventions on the opioid epidemic, and one on the effects of air pollution on school absences. The first two chapters were coauthored with Shiyu Zhang, a former Caltech graduate student. The first chapter examines the market for prescription opioids following the OxyContin Reformulation, an event that made OxyContin harder to misuse. Using detailed prescription opioid sales data from 2006 to 2014, we show that event did not reduce overdose deaths but led individuals to switch to generic oxycodone as a substitute for OxyContin. The second chapter examines geographic spillover effects from state prescription drug monitoring programs (PDMPs). We show that these policies reduce prescription opioid sales and opioid overdose deaths in the state they are enacted in. However, because they only track opioids sold locally, these programs induce individuals to drive across state lines to purchase opioids and avoid these regulations. The final chapter examines the effects of air pollution on NYC school absences using daily changes in wind direction. I show that PM2.5 and Ozone concentrations are strongly influenced by wind patterns, and exposure to these two pollutants causes detectable increases in absences over the following two days. Reductions in PM2.5 pollution over time have prevented approximately 381,000 absences annually in NYC which increases school funding by $19 million.</p

Pai contra Mãe na perspectiva atual da sociedade

O conto de Machado de Assis e sua relação com o direito de acordo com o contexto atual.&nbsp

Creep–Fatigue Interaction of Inconel 718 Manufactured by Electron Beam Melting

Electron beam melting of Ni-base superalloy Inconel 718 allows producing a columnar-grained microstructure with a pronounced texture, which offers exceptional resistance against high-temperature loading with severe creep–fatigue interaction arising in components of aircraft jet engines. This study considers the deformation, damage, and lifetime behavior of electron-beammelted Inconel 718 under in-phase thermomechanical fatigue loading with varying amounts of creep–fatigue interaction. Strain-controlled thermomechanical fatigue tests with equal-ramp cycles, slow–fast cycles, and dwell time cycles are conducted in the temperature range from 300 to 650 °C. Results show that both dwell time and slow–fast cycles promote intergranular cracking, gradual tensile stress relaxation, as well as precipitate dissolution and coarsening giving rise to cyclic softening. The interplay of these mechanisms leads to increased lifetimes in both dwell time and slow–fast tests compared to equal ramp tests at higher strain amplitudes. Conversely, at lower mechanical strain amplitudes, the opposite is observed. A comparison with results of conventional Inconel 718 indicates that the electron-beam-melted material exhibits superior resistance against strain-controlled loading at elevated temperatures such as thermomechanical fatigue

Persistent Topology of Syntax

We study the persistent homology of a data set of syntactic parameters of world languages. We show that, while homology generators behave erratically over the whole data set, non-trivial persistent homology appears when one restricts to specific language families. Different families exhibit different persistent homology. We focus on the cases of the Indo-European and the Niger–Congo families, for which we compare persistent homology over different cluster filtering values. The persistent components appear to correspond to linguistic subfamilies, while the meaning, in historical linguistic terms, of the presence of persistent generators of the first homology is more mysterious. We investigate the possible significance of the persistent first homology generator that we find in the Indo-European family. We show that it is not due to the Anglo-Norman bridge (which is a lexical, not syntactic phenomenon), but is related instead to the position of Ancient Greek and the Hellenic branch within the Indo-European phylogenetic network

Towards understanding interactions between Sustainable Development Goals: the role of environment–human linkages

Only 10 years remain to achieve all Sustainable Development Goals (SDGs) globally, so there is a growing need to increase the effectiveness and efficiency of action by targeting multiple SDGs. The SDGs were conceived as an ‘indivisible whole’, but interactions between SDGs need to be better understood. Several previous assessments have begun to explore interactions including synergies and possible conflicts between the SDGs, and differ widely in their conclusions. Although some highlight the role of the more environmentally-focused SDGs in underpinning sustainable development, none specifically focuses on environment-human linkages. Assessing interactions between SDGs, and the influence of environment on them, can make an important contribution to informing decisions in 2020 and beyond. Here, we review previous assessments of interactions among SDGs, apply an influence matrix to assess pairwise interactions between all SDGs, and show how viewing these from the perspective of environment-human linkages can influence the outcome. Environment, and environment-human linkages, influence most interactions between SDGs. Our action-focused assessment enables decision makers to focus environmental management to have the greatest impacts, and to identify opportunities to build on synergies and reduce trade-offs between particular SDGs. It may enable sectoral decision makers to seek support from environment managers for achieving their goals. We explore cross-cutting issues and the relevance and potential application of our approach in supporting decision making for progress to achieve the SDGs

Potentiation of zinc stress caused by parasitic infection of snails

The purpose of this experiment was to determine the effects of parasitism ( Schistosomatium douthitti Price and Trichobilharzia sp.) on the tolerance of snails Lymnaea stagnalis (L.) to acutely lethal concentrations of zinc. Significant reduction in tolerance occurred for snails with patent infections at 24 and 75 ppm of Zn ++ . At two selected prepatent levels of parasite development, significant differences occurred at the higher concentration only.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42902/1/10750_2004_Article_BF00017554.pd

Customer focused incident monitoring in anaesthesia

The database of incident forms relating to anaesthesia services in an institutional risk management programme were reviewed for 2003-2005, the aim being to identify any recurring patterns. Incidents were prospectively categorised as relating to attitude/behaviour, communication breakdown, delay in service, or were related to care, cost, environment, equipment, security, administrative process, quality of service or miscellaneous. The total number of anaesthesia-related incidents reported during the period was 287, which related to 0.44% of the total number of anaesthetics administered during the time period. In all, 170 incidents were reported by the department, 96 by internal customers and 21 by external customers. Only 30% of the complaints came from the operating room. Thirty-four per cent of all incidents related to communication, behaviour and delay in service. A requirement to teach communication skills and stress handling formally in anaesthesia training programmes, and at the time of induction of staff into the department, has been identified

Nonthermal Supermassive Dark Matter

We discuss several cosmological production mechanisms for nonthermal supermassive dark matter and argue that dark matter may be elementary particles of mass much greater than the weak scale. Searches for dark matter should not be limited to weakly interacting particles with mass of the order of the weak scale, but should extend into the supermassive range as well.Comment: 11 page LaTeX file. No major changes. Version accepted by PR