A modality-adaptive method for segmenting brain tumors and organs-at-risk in radiation therapy planning

In this paper we present a method for simultaneously segmenting brain tumors and an extensive set of organs-at-risk for radiation therapy planning of glioblastomas. The method combines a contrast-adaptive generative model for whole-brain segmentation with a new spatial regularization model of tumor shape using convolutional restricted Boltzmann machines. We demonstrate experimentally that the method is able to adapt to image acquisitions that differ substantially from any available training data, ensuring its applicability across treatment sites; that its tumor segmentation accuracy is comparable to that of the current state of the art; and that it captures most organs-at-risk sufficiently well for radiation therapy planning purposes. The proposed method may be a valuable step towards automating the delineation of brain tumors and organs-at-risk in glioblastoma patients undergoing radiation therapy

Transformational responses to climate change: beyond a systems perspective of social change in mitigation and adaptation

There is a growing imperative for responses to climate change to go beyond incremental adjustments, aiming instead for society-wide transformation. In this context, sociotechnical (ST) transitions and social–ecological (SE) resilience are two prominent normative agendas. Reviewing these literatures reveals how both share a complex-systems epistemology with inherent limitations, often producing managerial governance recommendations and foregrounding material over social drivers of change. Further interdisciplinary dialogue with social theory is essential if these frameworks are to become more theoretically robust and capable of informing effective, let alone transformational, climate change governance. To illustrate this potential, ideas from Deleuze and Guattari's political writing as well as other approaches that utilize the notion social fields (as opposed to sociosystems) are combined to more fully theorize the origins and enactment of social change. First, the logic of systems is replaced with the contingency of assemblages to reveal how pluralism, not elitism, can produce more ambitious and politicized visions of the future. In particular, this view encourages us to see social and ecological tensions as opportunities for thinking and acting differently rather than as mere technical problems to be solved. Secondly, the setting of social fields is introduced to situate and explain the power of ideas and the role of agency in times of uncertainty. The potential of such insights is already visible in some strands of climate change mitigation and adaptation research, but more needs to be done to advance this field and to bring it into dialogue with the mainstream systems based literature