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Modeling of space crop-Based dishes for optimal nutrient delivery to astronauts and beyond on Earth
No full textFuture long-term human exploration of space will need a supply of resources for astronauts, including fresh food from space farms. This means it is necessary to identify combinations of crops that can be successfully grown together and which provide a balanced and palatable diet for astronauts. We used numerical optimization to identify such combinations, using macro- and micronutritional content as constraints, while optimizing water load needed for crop farming. The food constraints considered were based on the recommendations of the National Aeronautics and Space Administration (NASA), considering up to 36 nutrients and 102 crops. We evaluated 10 scenarios (“space dishes”) for daily full-nutrient supply to one astronaut, with four scenarios being vegetarian (crops only) and six being omnivorous (crops and meat). Each scenario was analyzed for the capability of plant growth, including the required planting area and crop growth time and productivity; from the viewpoint of optimizing performance in space. As plants contain both edible and inedible parts and require fertilizer input, respective circularity assessments were made determining the waste generation, degree of recyclability, and overall mass processed, using three common metrics of the circular economy. The space dish identified as optimal was prepared as a salad, to allow judgment on the palatability, i.e., the “space food acceptance,” by a small psychology test. These assessments are essential steps toward feasibility in long-term human space missions, for example, to Mars
Turning points in leadership : ship size in the Portuguese and Dutch merchant empires
Get PDFThis paper discusses the implications of organizational control on the race for technological leadership in merchant empires. I provide an illustrative framework in which poor organizations have reduced incentives to invest, which in turn stifle technology improvements making leaders lag new entrants. In the late sixteenth century, Portugal’s large ships carried more merchandise and were more fitting of the monarch’s grandiose preferences, but they also were more prone to disaster. The merchant-controlled Dutch East India Company however, invested in smaller but more seaworthy vessels conducting more voyages at a much lower loss rate. The surviving historical evidence shows Portugal relying on large ships well into the seventeenth century suggesting her technological edge was gone by the time the Dutch dominated the Indian Ocean
Mental health trajectories in adolescents during Covid-19 : ‘are we all in this together’?
No full textThis study used a longitudinal, probability sample survey, Understanding Society Covid-19, to examine trajectories in adolescents’ mental health, via the Strengths and Difficulties Questionnaire, at three timepoints during Covid-19 with a particular emphasis on vulnerable groups (i.e., young carers, adolescent girls, BAME -Black, Asian and minority ethnic-, and adolescents in financially strained households). Generally, self-reports of emotional and total difficulties remained stable during the pandemic although adolescents who had limited social support were far more likely to report severe emotional and total difficulties than those who did not. Young people with pre-existing mental and physical health conditions appeared more resilient whereas vulnerable young people were hit the hardest during the pandemic. Compared to their less vulnerable peers, young carers, adolescent girls, Black or mixed-race young people, and adolescents in financially strained households were more likely to report reduced mental health during the pandemic. It is hoped the findings will contribute to debates about the pandemic unveiling existing mental health inequalities in society, and to public policy in an era of perma-crises as we currently face a cost-of-living crisis where public services are under enormous strain to reach those who need them most
Synthesis of lipid-linked precursors of the bacterial cell wall is governed by a feedback control mechanism in Pseudomonas aeruginosa
No full textMany bacterial surface glycans such as the peptidoglycan (PG) cell wall are built from monomeric units linked to a polyprenyl lipid carrier. How this limiting carrier is distributed among competing pathways has remained unclear. Here we describe the isolation of hyperactive variants of Pseudomonas aeruginosa MraY, the enzyme that forms the first lipid-linked PG precursor. These variants result in the elevated production of the final PG precursor lipid II in cells and are hyperactive in vitro. The activated MraY variants have substitutions that map to a cavity on the extracellular side of the dimer interface, far from the active site. Our structural and molecular dynamics results suggest that this cavity is a binding site for externalized lipid II. Overall, our results support a model in which excess externalized lipid II allosterically inhibits MraY, providing a feedback mechanism that prevents the sequestration of lipid carrier in the PG biogenesis pathway
Foetal exposure to air pollution and students’ cognitive performance : evidence from agricultural fires in Brazil
Get PDFThis paper examines the impact of foetal exposure to air pollution from agricultural fires on Brazilian students' cognitive performance later in life. We rely on comparisons across children who were upwind and downwind of the fires while in utero to address concerns around sorting and temporary income shocks. Our findings show that agricultural fires increase , resulting in significant negative effects on pupils' scores in Portuguese and Maths in the grade through prenatal exposure. Back-of-the-envelope calculations suggest that a 1% reduction in from agricultural burning has the potential to increase later life wages by 2.6%
From green crap to net zero : Conservative climate policy 2015–2022
No full textThis article outlines the Conservative Party’s approach to climate change from 2015 to 2022; focusing on its governing policy record and the wider political considerations that shaped it. During this time, the Conservatives’ mixed performance reflected competing political incentives for its leaders and internal party division on the issue. A detailed exploration of Conservative climate policies allows for two broader contributions. European centre-right parties often face common strategic challenges, such as competition from the radical right, but the UK Conservative Party case study shows that responding to these challenges does not necessarily demand the abandonment of climate commitments. We also find evidence that in this period climate change embodied characteristics of both a positional and a valence issues
Mexico's Dirty War : a reassessment
Get PDFRecent scholarship has found that Mexico's dirty war was rooted in existing, but also limited, violent practices established during the 1940s and 1950s. During the 1960s, these limits began to disappear. But it was not until the early 1970s when the state had sufficient capacity to launch counterinsurgency tactics throughout the nation. However, contrary to traditional appreciations of Mexico's dirty war, these tactics were not exclusively used on urban and rural insurgents. They were soon employed by soldiers, secret agents and state cops often in alliance with local landowners and their pistoleros. They focused these violent practices on land invaders, groups aiming at indigenous autonomy, drug traffickers and drug producers. La tibieza ya se acabó, esto es una guerra a muerte (The softly-softly approach is over, this is a war to the death) Durazo Moreno, April 1977
The moment of patient safety : iatrogenic injury, clinical error, and cultures of healthcare in the NHS
Get PDFThis article explores the ‘the moment of patient safety’—the period around 2000 when patient safety became a key policy concern of the British National Health Service (NHS), and other healthcare systems. While harm caused by medical care (iatrogenic injury) had long been acknowledged by clinicians and scientists, from 2000 a new systemic language of patient safety emerged in the NHS that promoted novel managerial and regulatory approaches to patient harm. This language
reflected the state’s increasing role in regulating healthcare, as well as the erosion of medical autonomy and the rise of new forms of bureaucratic management.
Acknowledging a transnational, intellectual context behind the rise of policy interest in patient safety—for example, the application of insights from the industrial safety sciences—this article examines the role played by domestic cultural factors, such as medical negligence litigation and healthcare scandals, in helping to define the new language in Britai
