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Within a context of cultural- and land-based Indigenous resurgence, contemporary Indigenous writers, artists, theorists, and activists have made the settler-state and extraction economy of Canada a flashpoint of the global climate emergency. Indigenous peoples often exist on the front lines of climate change, finding their lives and livelihoods threatened by the effects of rising temperatures even as they have been excluded from many of the benefits afforded by carbon-intensive economies. This chapter examines how Indigenous writers place climate change within a long, ongoing history of colonial resource appropriations, ecological loss, and violent suppression of Indigenous bodies and cultures in Canada. The chapter also addresses the diverse ways they respond to its challenges, including: crafting texts and practices of political dissent, solidarity-building, and land reoccupation; grounding present experiences in enduring stories of Indigenous response to environmental and political change; and refashioning genres such as science fiction, horror, or post-apocalyptic imaginaries to explore Indigenous futurisms in a climate-altered world. Above all, Indigenous writers make clear that climate change cannot be extricated from decolonisation and matters of sovereignty. The restoration of Indigenous lands and land-based ways of knowing is the starting point for the pursuit of climate justice.
What’s fair? The cries of the playground – “that’s fair,” “that’s not fair” – echo throughout our adult lives. Sometimes an entire society’s understanding of what’s fair shifts in a decade, a year, even a single day. Children of Jehovah’s Witnesses refuse to salute the flag in school and change the way a nation views the First Amendment. Oliver Brown thinks it’s unfair that his daughter can’t attend her neighborhood school.
Traversodontidae is a group of Triassic herbivorous/omnivorous cynodonts that represents the most diversified lineage within Cynognathia. In southern Brazil, a rich fossil record of late Middle/mid-Late Triassic cynodonts has been documented, with Exaeretodon riograndensis Abdala, Barberena, and Dornelles, 2002 and Siriusgnathus niemeyerorum Pavanatto et al., 2018 representing two abundant and well-documented traversodontids. The present study provides a comparative analysis of the morphology of the nasal cavity, nasal recesses, nasolacrimal duct, and maxillary canals of both species using computed tomography, highlighting the changes that occurred in parallel to the origin of mammaliaforms. Our results show that there were no ossified turbinals or a cribriform plate delimiting the posterior end of the nasal cavity, suggesting these structures were probably cartilaginous as in nonmammaliaform cynodonts. Both species show lateral ridges on the internal surface of the roof of the nasal cavity, but the median ridge for the attachment of a nasal septum is absent. Exaeretodon riograndensis and S. niemeyerorum show recesses on the dorsal region of the nasal cavity, which increase the volume of the nasal cavity, potentially enhancing the olfactory chamber and contributing to the sense of smell. On the lateral sides of the nasal cavity, the analyzed taxa show a well-developed maxillary recess. Although E. riograndensis and S. niemeyerorum have roughly similar nasal cavities, in the former taxon, the space between the left and right dorsal recesses of the nasal cavity is uniform along its entire extension, whereas this space narrows posteriorly in S. niemeyerorum. Finally, the nasolacrimal duct of S. niemeyerorum is more inclined anteroposteriorly than in E. riograndensis.
The VISCACHA (VIsible Soar photometry of star Clusters in tApii and Coxi HuguA†) Survey is an ongoing project based on deep and spatially resolved photometric observations of Magellanic Cloud star clusters, collected using the SOuthern Astrophysical Research (SOAR) telescope together with the SOAR Adaptive Module Imager. So far we have used >300h of telescope time to observe ∼150 star clusters, mostly with low mass (M < 104M⊙) on the outskirts of the LMC and SMC. With this high-quality data set, we homogeneously determine physical properties using deep colour-magnitude diagrams (ages, metallicities, reddening, distances, mass, luminosity and mass functions) and structural parameters (radial density profiles, sizes) for these clusters which are used as a proxy to investigate the interplay between the Magellanic Clouds and their evolution. We present the VISCACHA survey and its initial results, based on our first two papers. The project’s long term goals and expected legacy to the community are also addressed.
Investigations into the existence of life in other parts of the cosmos find strong parallels with studies of the origin and evolution of life on our own planet. In this way, astrobiology and paleobiology are married by their common interest in disentangling the interconnections between life and the surrounding environment. In this way, a cross-point of both sciences is paleometry, which involves a myriad of imaging and geochemical techniques, usually non-destructive, applied to the investigation of the fossil record. In the last decades, paleometry has benefited from an unprecedented technological improvement, thus solving old questions and raising new ones. This advance has been paralleled by conceptual approaches and discoveries fuelled by technological evolution in astrobiological research. In this context, we present some new data and review recent advances on the employment of paleometry to investigations on paleobiology and astrobiology in Brazil in areas such biosignatures in Ediacaran microbial mats, biogenicity tests on enigmatic Ediacaran structures, research on Ediacaran metazoan biomineralization, fossil preservation in Cretaceous insects and fish, and finally the experimental study on the decay of fish to test the effect of distinct types of sediment on soft-tissue preservation, as well as the effects of early diagenesis on fish bone preservation.
MG/HK was introduced into CMOS technology and enabled scaling beyond the 45/32nm technology node. The change in gate stack from poly-Si/SiON to MG/HK introduced new reliability challenges like the positive bias temperature instability (PBTI) and stress induced leakage currents (SILC) in nFET devices which prompted thorough investigation to provide fundamental understanding of these degradation mechanisms and are nowadays well understood. The shift to a dual-layer gate stack also had a profound impact on the time dependent dielectric breakdown (TDDB) introducing a strong polarity dependence in the model parameter. As device scaling continues, stochastic modeling of variability, both at time zero and post stress due to BTI, becomes critical especially for SRAM circuit aging. As we migrate towards novel device architectures like bulk FinFET, SOI FinFETs, FDSOI and gate-all-around devices, impact of self-heating needs to be accounted for in reliability testing.
In this paper we summarize the fundamentals of MG/HK reliability and discuss the reliability and characterization challenges related to the scaling of future CMOS technologies.
We observed the Planetary Nebula NGC 6720 with the Gemini Telescope and the Gemini Multi-Object Spectrographs. We obtained spatial maps of 36 emission-lines in the wavelength range between 3600 Å and 9400 Å. We derived maps of c(Hβ), electronic densities, electronic temperatures, ionic and elemental abundances, and Ionization Correction Factors (ICFs) in the source and investigated the mass-loss history of the progenitor. The elemental abundance results indicate the need for ICFs based on three-dimensional photoionization models.
What’s fair? The cries of the playground – “that’s fair,” “that’s not fair” – echo throughout our adult lives. Sometimes an entire society’s understanding of what’s fair shifts in a decade, a year, even a single day. Children of Jehovah’s Witnesses refuse to salute the flag in school and change the way a nation views the First Amendment. Oliver Brown thinks it’s unfair that his daughter can’t attend her neighborhood school. Rosa Parks refuses to give up her seat on a Montgomery bus. Together they change definitions of what counts as equality. Sometimes you go to sleep one night, and when you wake up, the rules have changed. That happened on November 22, 1971, when the U.S. Supreme Court ruled for the first time that arbitrary discrimination on the basis of sex could be a denial of equal protection of the laws.
The case that triggered this shift was a modest one. It came from a small state (Idaho) and involved hardly any money ($930, which lawyers’ fees completely consumed). To most people, the dispute seemed merely a family squabble, hardly worth the expensive attention it would get. It is the rare constitutional law casebook in which it figures in more than a footnote. Yet Sally Reed’s complaint was far from trivial. It disrupted well-established rules of fairness and spurred broad social transformation in the ways that both men and women make some of the most important choices in their lives.
We introduce a strategy based on Kustin–Miller unprojection that allows us to construct many hundreds of Gorenstein codimension 4 ideals with 9×16 resolutions (that is, nine equations and sixteen first syzygies). Our two basic games are called Tom and Jerry; the main application is the biregular construction of most of the anticanonically polarised Mori Fano 3-folds of Altınok’s thesis. There are 115 cases whose numerical data (in effect, the Hilbert series) allow a Type I projection. In every case, at least one Tom and one Jerry construction works, providing at least two deformation families of quasismooth Fano 3-folds having the same numerics but different topology.
The enormous burden of almost 3.6 million neonatal deaths remains relatively invisible because of gaps in data or ineffective use of existing data, the perceived complexity and expense of solutions, and societal norms for seclusion of newborns and acceptance of neonatal deaths.
The data for action for neonatal survival highlight many commonalities with maternal survival and indeed mothers and their babies are intimately linked. Stillbirths are not mentioned in Millennium Development Goal (MDG) 4 or 5, yet they are largely preventable with the same solutions. Previous false dichotomies in advocacy and programmes for maternal and newborn survival have not been helpful in accelerating progress. An integrated call for action would be more likely to increase global visibility and national action. Health professionals and policy makers need to link numbers for mothers, newborns and stillbirths together, and to work together to implement the highest impact solutions that save women and babies.
This chapter reviews the progress for MDG 4 (child survival), with a focus on neonatal survival and on highlighting linkages with MDG 5 (maternal survival). Priorities for programmatic action based on the data are identified.
Progress for neonatal and child survival
The MDGs are the most widely ratified health and development targets ever. Nearly every nation has agreed to reach these eight interlinking goals that address poverty, hunger, education and health by 2015. Multiple reports have been published and many commitments have been agreed but is progress being made?
VISIR, the VLT Imager and Spectrograph for the Mid-Infrared is a multi-mode instrument, featuring also a high resolution Echelle spectrograph with a spectral resolving power of ≈30 000 or 10 km s−1 at ν ≈ 30 000 GHz (λ ≈ 10 μm). A limited long-slit mode as well as a general cross-dispersed mode are available. The Echelle grating is illuminated with a 200 mm diameter collimated beam. Cross-dispersion is achieved by a pair of grisms in the pre-slit optics. The entire frequency interval corresponding to the “10 μ m-window” from 22 400 to 39 500 GHz is fully accessible, albeit sequentially. This interval contains a multitude of fundamental molecular rotational-vibrational bands such as SiO, OH−, H2O, NH3, CH4 and many other hydro-carbonates. Since its commissioning in April 2004, VISIR has been plagued by artifacts introduced from its detector. The cross-dispersed mode is especially handicapped, as it is the most demanding mode for dynamic range of illumination. Now an ambitious upgrade with a pair of newly developed 1k2 As:Si detectors is underway, which will fully resurrect the spectroscopic mode. This will also increase the frequency interval accessible in one exposure by 240% while changing from critical to 3-pixel sampling. Even in the absence of extra spectral features this increase is quite valuable for absorption line spectroscopy, as the limiting factor in analysis often is the definition of the photospheric continuum.
Water vapour is the principle source of opacity at infrared wavelengths in the earth's atmosphere. Measurements of atmospheric water vapour serve two primary purposes when considering operation of an observatory: long-term monitoring of precipital water vapour (PWV) is useful for characterizing potential observatory sites, and real-time monitoring of PWV is useful for optimizing use, in particular for mid-IR observations.
We present results of a project aimed at establishing a set of 12 spectro-photometric standards over a wide wavelength range from 320 to 2500 nm. Currently no such set of standard stars covering the near-IR is available. Our strategy is to extend the useful range of existing well-established optical flux standards (Oke 1990, Hamuy et al. 1992, 1994) into the near-IR by means of integral field spectroscopy with SINFONI at the VLT combined with state-of-the-art white dwarf stellar atmospheric models (TMAP, Holberg et al. 2008). As a solid reference, we use two primary HST standard white dwarfs GD71 and GD153 and one HST secondary standard BD+17 4708. The data were collected through an ESO “Observatory Programme” over ~40 nights between February 2007 and September 2008.
Infrared astronomy has come into its own over the last decade. Based on mature detector technology and sophisticated instrumentation it is contributing exciting science in many fields of astrophysics. Stellar evolution is a field that has long been dominated by ultraviolet and optical work, but one that has benefited from a strongly increasing contribution from the infrared (IR) and sub-millimeter (sub-mm) domains. In particular, spectroscopy in these domains holds the promise to enable important advances through quantitative analysis of individual stars and stellar systems.
A few star clusters in the Magellanic Clouds exhibit composite structures in the red-clump region of their colour–magnitude diagrams. The most striking case is NGC 419 in the Small Magellanic Cloud (SMC), where the red clump is composed of a main blob as well as a distinct secondary feature. This structure is demonstrated to be real and corresponds to the simultaneous presence of stars which passed through electron degeneracy after central-hydrogen exhaustion and those that did not. This rare occurrence in a single cluster allows us to set stringent constraints on its age and on the efficiency of convective-core overshooting during main-sequence evolution. We present a more detailed analysis of NGC 419, together with a first look at other populous Large Magellanic Cloud clusters which are apparently in the same phase: NGC 1751, NGC 1783, NGC 1806, NGC 1846, NGC 1852 and NGC 1917. We also compare these Magellanic Cloud cases with their Galactic counterparts, NGC 752 and NGC 7789. We emphasise the extraordinary potential of these clusters as absolute calibration marks on the age scale of stellar populations.
Open cluster remnants (OCRs) are fundamental objects to investigate open cluster dissolution processes (e.g., Bica et al. 2001; Carraro 2002; Pavani et al. 2003; Carraro et al. 2007; Pavani & Bica 2007). They are defined as poorly populated concentrations of stars, with enough members to show evolutionary sequences in colour–magnitude diagrams (CMDs) as a result of the dynamical evolution of an initially more massive physical system. An OCR is intrinsically poorly populated, which makes its differentiation from field-star fluctuations difficult. Among the possible approaches to establish the nature of OCRs, we adopted CMD analysis combined with a robust statistical tool applied to 2mass data. In addition, photometry is the main information source available for possible OCRs (POCRs). We developed a statistical diagnostic tool to analyse the CMDs of POCRs and verify them as physical systems, explore membership probabilityies taking into account field contamination and derive age, distance and reddening values in a self-consistent way. We present the results of our analysis of 88 POCRs that are part of a larger sample that is widely distributed across the sky, with a significant density contrast of bright stars compared to the Galactic field. The 88 objects are projected onto low-density Galactic fields, at relatively high latitudes (|b| > 15°). Studies of larger POCR samples will provide a better understanding of OCR properties and constraints for theoretical models, including new insights into the evolution of open clusters and their dissolution rates. The results of this ongoing survey will provide a general picture of these fossil stellar systems and their connection to Galactic-disk evolution.
Analysis of integrated spectra of star clusters in the Magellanic Clouds can bring important information for studies on the chemical evolution of the Clouds. The aim of the present work is to derive ages and metallicities from integrated spectra of 15 star clusters in the Small Magellanic Cloud (SMC), some of them not studied so far. Making use of a full spectrum fitting technique, we compared the integrated spectra of the sample clusters to three different sets of single stellar population models available in the literature. We derived ages and metallicities for the sample clusters employing the codes STARLIGHT and ULySS. Out of the 15 clusters in our sample, 9 are old/intermediate age clusters and 6 are young clusters. We point out the results for the newly identified as old/intermediate age clusters HW1, NGC 152, Lindsay 3 and 11. We also confirm old ages for NGC 361, NGC 419 and Kron 3, and the oldest well-known SMC cluster NGC 121.