VLTI-MATISSE chromatic aperture-synthesis imaging of η Carinae\u27s stellar wind across the Br α line: Periastron passage observations in February 2020

Context. Eta Carinae is a highly eccentric, massive binary system (semimajor axis ~15.5 au) with powerful stellar winds and a phase-dependent wind-wind collision (WWC) zone. The primary star, η Car A, is a luminous blue variable (LBV); the secondary, η Car B, is a Wolf-Rayet or O star with a faster but less dense wind. Aperture-synthesis imaging allows us to study the mass loss from the enigmatic LBV η Car. Understanding LBVs is a crucial step toward improving our knowledge about massive stars and their evolution. Aims. Our aim is to study the intensity distribution and kinematics of η Car\u27s WWC zone. Methods. Using the VLTI-MATISSE mid-infrared interferometry instrument, we perform Brα imaging of η Car\u27s distorted wind. Results. We present the first VLTI-MATISSE aperture-synthesis images of η Car A\u27s stellar windin several spectral channels distributed across the Brα 4.052 μm line (spectral resolving power R ~ 960). Our observations were performed close to periastron passage in February 2020 (orbital phase ~ 14.0022). The reconstructed iso-velocity images show the dependence of the primary stellar wind on wavelength or line-of-sight (LOS) velocity with a spatial resolution of 6 mas (~14 au). The radius of the faintest outer wind regions is ~26 mas (~60 au). At several negative LOS velocities, the primary stellar wind is less extended to the northwest than in other directions. This asymmetry is most likely caused by the WWC. Therefore, we see both the velocity field of the undisturbed primary wind and the WWC cavity. In continuum spectral channels, the primary star wind is more compact than in line channels. A fit of the observed continuum visibilities with the visibilities of a stellar wind CMFGEN model (CMFGEN is an atmosphere code developed to model the spectra of a variety of objects) provides a full width at half maximum fit diameter of the primary stellar wind of 2.84 ± 0.06 mas (6.54 ± 0.14 au). We comparethe derived intensity distributions with the CMFGEN stellar wind model and hydrodynamic WWC models

Machine learning–driven multiscale modeling reveals lipid-dependent dynamics of RAS signaling proteins

RAS is a signaling protein associated with the cell membrane that is mutated in up to 30% of human cancers. RAS signaling has been proposed to be regulated by dynamic heterogeneity of the cell membrane. Investigating such a mechanism requires near-atomistic detail at macroscopic temporal and spatial scales, which is not possible with conventional computational or experimental techniques. We demonstrate here a multiscale simulation infrastructure that uses machine learning to create a scale-bridging ensemble of over 100,000 simulations of active wild-type KRAS on a complex, asymmetric membrane. Initialized and validated with experimental data (including a new structure of active wild-type KRAS), these simulations represent a substantial advance in the ability to characterize RAS-membrane biology. We report distinctive patterns of local lipid composition that correlate with interfacially promiscuous RAS multimerization. These lipid fingerprints are coupled to RAS dynamics, predicted to influence effector binding, and therefore may be a mechanism for regulating cell signaling cascades

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

[This corrects the article DOI: 10.1186/s13054-016-1208-6.]

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

From threat to opportunity: Spatial strategies integrating urban and water dynamics towards a sustainable redevelopment model for informal settlements in Mexico City’s periphery

This thesis tells a story of today, of Mexico City, and a plan for a desirable future for the Municipality of Valle de Chalco, an informal settlement affected by the metropolitan mismanagement of water resources. Today uneven developments dominate in Mexico City Metropolitan Area, a result of a Neoliberal urbanization process. The current urban reality is the result of the unbalanced power relations between the city makers that priorities the city core and the city dwellers that are pushed into urban poverty towards peripheral areas. Those areas are not perceived as part of the city and therefore experience water related problems: flooding and lack of basic services such as safe water supply and sanitation. The Neoliberal policies in the urban process had emphasized the class polarization of the citizens. Valle de Chalco Solidaridad at the south-east periphery of the city is a fine example of a marginalized society in struggle. Moreover, the rapid population growth has led human interventions to affect natural processes and contribute to the growing destruction of natural ecosystems. The story of the natural ecosystems coevolves with the story of the development of Mexico City’s settlement. The human story intersects with that of nature. Until today humans had gain at the expense of nature, which moves ineluctably towards ecological disequilibrium. Current risks of flooding and fresh water scarcity that Mexico City Metropolitan Area is facing will increase if the denial for interaction between the city and water continues. A city that once was an island in complete synergism with water needs to learn how to live with it again and create opportunities from the interaction with it. The desirable is a win-win situation in which harmony between humans and their natural environment is re-established.MSc Spatial Planning and Urban Design - [TISD] Technology in Sustainable Development SpecializationUrbanismArchitectur

Isothermal Phase Transformations Below the Martensite Start Temperature in a Low-Carbon Steel

Advanced High Strength Steels (AHSS) have been used extensively for the last three decades in the automotive industry as they exhibit an enhanced combination of strength and ductility which has successfully allowed the weight reduction of structural components. This breakthrough has been highly beneficial for the environment, as lighter vehicles have reduced the CO2 emissions during use. In the last decade, the development of AHSS has been focused on the design of complex microstructures containing high strength phases, such as bainite and martensite, as well as a softer phase providing ductility and strain hardening, such as austenite. However, the thermomechanical processing of these multiphase steels requires long, complex, and energy-intensive thermal treatments with a high environmental footprint. New alternative processing routes are being developed for producing these multiphase steels sustainably, without compromise on strength and ductility, thus achieving reduced CO2 emissions throughout the lifecycle of steel. In this framework, a new thermal treatment consisting of a rapid cooling below the martensite start temperature (Ms) followed by an isothermal treatment at the same quenching temperature is proposed as a promising environmentally sustainable alternative for the production of such multiphase steels. This Ph.D. thesis investigates, from a scientific point of view, the phase transformations and the interactions between the phases formed during the above-described novel isothermal treatment below Ms in a low-carbon high-silicon steel. The thermal treatment is applied in different combinations of quenching temperature and isothermal holding time in order to stimulate the formation of diverse phase fraction mixtures. The research also elucidates the effects of the formation of each of the phases on the microstructure-property relationships of these multiphase steels.(OLD) MSE-

Space and crime in Dutch built environments: Macro and micro scale spatial conditions for residential burglaries and thefts from cars

At this moment, more knowledge is available on the physical characteristics of the built environment and their relationship to criminal opportunity rather than the spatial characteristics of potential targets and the public and private space between them. To improve this situation, a research project was started in the Dutch cities Gouda and Alkmaar that aimed to address several spatial characteristics of the built environment, to develop a method to quantify these characteristics and to relate them to the geographic distribution of residential burglaries and thefts from carsi. The predominant task consisted in identifying the spatial conditions on various scale levels - in terms of the street net’s configuration - and the relationship between private and public space favouring burglaries and theft from cars. Furthermore, statistical analysis was used to study the relationship between crime risk and spatial configuration on various scale levels.UrbanismArchitecture and The Built Environmen

Micro scale spatial relationships in urban studies: The relationship between private and public space and its impact on street life

Research on urban environment by means of space syntax theory and methods tends to focus on macro scale spatial conditions. However, micro scale conditions should not be neglected. In research on street life and dispersal of crime in urban areas, it became inevitable to pay attention to the interdependence between the macro as well as the micro scale spatial conditions. For this purpose, spatial analyses methods were developed and tested in the Dutch towns Alkmaar and Gouda as regards topological relationships between private and public space. In particular inter-visibility of windows and doors and their inter-relationship to street segments were taken into account. Other variables were the density of entrances of private houses connected to streets, the topological depth between various kinds of private and public space, the degree of constitutedness of street segments and the degree of visibility from windows to parking lots. The application of these tools in the analyses on built environments shows clearly that micro scale spatial relationships have impact on street life and street safety in urban areas.UrbanismArchitecture and The Built Environmen

Effect of Prior Athermal Martensite on the Isothermal Transformation Kinetics Below M s in a Low-C High-Si Steel

Thermomechanical processing of Advanced Multiphase High Strength Steels often includes isothermal treatments around the martensite start temperature (M s). It has been reported that the presence of martensite formed prior to these isothermal treatments accelerates the kinetics of the subsequent transformation. This kinetic effect is commonly attributed to the creation of potential nucleation sites at martensite-austenite interfaces. The aim of this study is to determine qualitatively and quantitatively the effect of a small volume fraction of martensite on the nucleation kinetics of the subsequent transformation. For this purpose, dilatometry experiments were performed at different temperatures above and below the M s temperature for athermal martensite in a low-carbon high-silicon steel. Microstructural analysis led to the identification of the isothermal decomposition product formed above and below M s as bainitic ferrite. The analysis of the transformation processes demonstrated that the initial stage of formation of bainitic ferrite at heat treatments below M s is at least two orders of magnitude faster than above M s due to the presence of martensite.Materials Science and EngineeringMechanical, Maritime and Materials Engineerin