1,324 research outputs found
Understanding the Logistics for the Distribution of Heme in Cells
[Image: see text] Heme is essential for the survival of virtually all living systems—from bacteria, fungi, and yeast, through plants to animals. No eukaryote has been identified that can survive without heme. There are thousands of different proteins that require heme in order to function properly, and these are responsible for processes such as oxygen transport, electron transfer, oxidative stress response, respiration, and catalysis. Further to this, in the past few years, heme has been shown to have an important regulatory role in cells, in processes such as transcription, regulation of the circadian clock, and the gating of ion channels. To act in a regulatory capacity, heme needs to move from its place of synthesis (in mitochondria) to other locations in cells. But while there is detailed information on how the heme lifecycle begins (heme synthesis), and how it ends (heme degradation), what happens in between is largely a mystery. Here we summarize recent information on the quantification of heme in cells, and we present a discussion of a mechanistic framework that could meet the logistical challenge of heme distribution
Environmental and Resource Economics: Some Recent Developments by
A first draft of this paper was prepared when the authors were visiting the Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, during April-May 2004. The current version was completed in Colombo, Sri Lanka, in June 2004, while the authors were attending the bi-annual teaching and research workshop of the South Asian Network for Development and Environmental Economics (SANDEE). We are most grateful to K. Sreenivasan (Director of ICTP), and Manik Duggar and Priya Shyamsundar (respectively, Programme Manager and Director of SANDEE), for making our visits both possible and most agreeable. Over the years, we have benefited greatly from discussions with Scott Barrett, William Brock, Stev
Powering sub-Saharan Africa’s urban revolution: An energy transitions approach
This paper develops a geographic understanding of urban energy transitions in subSaharan
African towns and cities. In doing so this paper seeks to critically reflect on the
value and limits of urban transitions analysis as a framework for understanding energy
networks beyond the largely integrated systems across the Global North. We explore how
these potentials and deficits can be addressed by examining promising developments
across a series of debates in urban studies that can help sensitise this approach to
energyscapes in the African context. By reviewing urban transi- tions analysis through
these debates the paper offers four important contributions to expand existing ways of
understanding energy transition. These include the particular urbanisation dynamics of
African towns ands cities, the need to locate the urban across energy regimes, the
agencies of various intermediaries and urban actors and the contested politics inherent in
the governing of energy networks. In the conclusion we reflect on the specific directions
that have emerged from the paper in relation to our contributions, offering a
geographically informed framework that allows us to better examine the challenges and
specificities of transition across these rapidly growing urban regions
Use of Non-concurrent Common Control in Master Protocols in Oncology Trials: Report of an American Statistical Association Biopharmaceutical Section Open Forum Discussion
This article summarizes the discussions from the American Statistical
Association (ASA) Biopharmaceutical (BIOP) Section Open Forum that took place
on December 10, 2020 and was organized by the ASA BIOP Statistical Methods in
Oncology Scientific Working Group, in coordination with the US FDA Oncology
Center of Excellence. Diverse stakeholders including experts from international
regulatory agencies, academicians, and representatives of the pharmaceutical
industry engaged in a discussion on the use of non-concurrent control in Master
Protocols for oncology trials. While the use of non-concurrent control with the
concurrent control may increase the power of detecting the therapeutic
difference between a treatment and the control, the panelists had diverse
opinion on the statistical approaches for modeling non-concurrent and
concurrent controls. Some were more concerned about the temporality of the
non-concurrent control and bias introduced by different confounders related to
time, e.g., changes in standard of care, changes in patient population, changes
in recruiting strategies, changes in assessment of endpoints. Nevertheless, in
some situations such as when the recruitment is extremely challenging for a
rare disease, the panelists concluded that the use of a non-concurrent control
can be justified
A Theory of Natural Addiction
Economic theories of rational addiction aim to describe consumer behavior in the presence of habit-forming goods. We provide a biological foundation for this body of work by formally specifying conditions under which it is optimal to form a habit. We demonstrate the empirical validity of our thesis with an in-depth review and synthesis of the biomedical literature concerning the action of opiates in the mammalian brain and their eects on behavior. Our results
lend credence to many of the unconventional behavioral assumptions employed by theories of
rational addiction, including adjacent complementarity and the importance of cues, attention,
and self-control in determining the behavior of addicts. We oer evidence for the special case
of the opiates that "harmful" addiction is the manifestation of a mismatch between behavioral
algorithms encoded in the human genome and the expanded menu of choices faced by consumers in the modern world
Do adults with high functioning autism or Asperger Syndrome differ in empathy and emotion recognition?
The present study examined whether adults with high functioning autism (HFA) showed greater difficulties in (i) their self-reported ability to empathise with others and/or (ii) their ability to read mental states in others’ eyes than adults with Asperger syndrome (AS). The Empathy Quotient (EQ) and ‘Reading the Mind in the Eyes’ Test (Eyes Test) were compared in 43 adults with AS and 43 adults with HFA. No significant difference was observed on EQ score between groups, while adults with AS performed significantly better on the Eyes Test than those with HFA. This suggests that adults with HFA may need more support, particularly in mentalizing and complex emotion recognition, and raises questions about the existence of subgroups within autism spectrum conditions
Comparing nuclear power trajectories in Germany and the UK: from ‘regimes' to ‘democracies’ in sociotechnical transitions and Discontinuities
This paper focuses on arguably the single most striking contrast in contemporary major energy politics in Europe (and even the developed world as a whole): the starkly differing civil nuclear policies of Germany and the UK. Germany is seeking entirely to phase out nuclear power by 2022. Yet the UK advocates a ‘nuclear renaissance’, promoting the most ambitious new nuclear construction programme in Western Europe.Here,this paper poses a simple yet quite fundamental question: what are the particular divergent conditions most strongly implicated in the contrasting developments in these two countries. With nuclear playing such an iconic role in historical discussions over technological continuity and transformation, answering this may assist in wider understandings of sociotechnical incumbency and discontinuity in the burgeoning field of‘sustainability transitions’. To this end, an ‘abductive’ approach is taken: deploying nine potentially relevant criteria for understanding the different directions pursued in Germany and the UK. Together constituted by 30 parameters spanning literatures related to socio-technical regimes in general as well as nuclear technology in particular, the criteria are divided into those that are ‘internal’ and ‘external’ to the ‘focal regime configuration’ of nuclear power and associated ‘challenger technologies’ like renewables.
It is ‘internal’ criteria that are emphasised in conventional sociotechnical regime theory, with ‘external’ criteria relatively less well explored. Asking under each criterion whether attempted discontinuation of nuclear power would be more likely in Germany or the UK, a clear picture emerges. ‘Internal’ criteria suggest attempted nuclear discontinuation should be more likely in the UK than in Germany– the reverse of what is occurring.
‘External’ criteria are more aligned with observed dynamics –especially those relating to military nuclear commitments and broader ‘qualities of democracy’. Despite many differences of framing concerning exactly what constitutes ‘democracy’, a rich political science literature on this point is unanimous in characterising Germany more positively than the UK. Although based only on a single case,a potentially important question is nonetheless raised as to whether sociotechnical regime theory might usefully give greater attention to the general importance of various aspects of democracy in constituting conditions for significant technological discontinuities and transformations. If so, the policy implications are significant. A number of important areas are identified for future research, including the roles of diverse understandings and specific aspects of democracy and the particular relevance of military nuclear commitments– whose under-discussion in civil nuclear policy literatures raises its own questions of democratic accountability
Loving-kindness brings loving-kindness: The impact of Buddhism on cognitive self–other integration
The twilight of the Liberal Social Contract? On the Reception of Rawlsian Political Liberalism
This chapter discusses the Rawlsian project of public reason, or public justification-based 'political' liberalism, and its reception. After a brief philosophical rather than philological reconstruction of the project, the chapter revolves around a distinction between idealist and realist responses to it. Focusing on political liberalism’s critical reception illuminates an overarching question: was Rawls’s revival of a contractualist approach to liberal legitimacy a fruitful move for liberalism and/or the social contract tradition? The last section contains a largely negative answer to that question. Nonetheless the chapter's conclusion shows that the research programme of political liberalism provided and continues to provide illuminating insights into the limitations of liberal contractualism, especially under conditions of persistent and radical diversity. The programme is, however, less receptive to challenges to do with the relative decline of the power of modern states
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