5,214 research outputs found

    Financial and Economic Review 22.

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    Complexity Science in Human Change

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    This reprint encompasses fourteen contributions that offer avenues towards a better understanding of complex systems in human behavior. The phenomena studied here are generally pattern formation processes that originate in social interaction and psychotherapy. Several accounts are also given of the coordination in body movements and in physiological, neuronal and linguistic processes. A common denominator of such pattern formation is that complexity and entropy of the respective systems become reduced spontaneously, which is the hallmark of self-organization. The various methodological approaches of how to model such processes are presented in some detail. Results from the various methods are systematically compared and discussed. Among these approaches are algorithms for the quantification of synchrony by cross-correlational statistics, surrogate control procedures, recurrence mapping and network models.This volume offers an informative and sophisticated resource for scholars of human change, and as well for students at advanced levels, from graduate to post-doctoral. The reprint is multidisciplinary in nature, binding together the fields of medicine, psychology, physics, and neuroscience

    Surface-Based tools for Characterizing the Human Brain Cortical Morphology

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    Tesis por compendio de publicacionesThe cortex of the human brain is highly convoluted. These characteristic convolutions present advantages over lissencephalic brains. For instance, gyrification allows an expansion of cortical surface area without significantly increasing the cranial volume, thus facilitating the pass of the head through the birth channel. Studying the human brain’s cortical morphology and the processes leading to the cortical folds has been critical for an increased understanding of the pathological processes driving psychiatric disorders such as schizophrenia, bipolar disorders, autism, or major depression. Furthermore, charting the normal developmental changes in cortical morphology during adolescence or aging can be of great importance for detecting deviances that may be precursors for pathology. However, the exact mechanisms that push cortical folding remain largely unknown. The accurate characterization of the neurodevelopment processes is challenging. Multiple mechanisms co-occur at a molecular or cellular level and can only be studied through the analysis of ex-vivo samples, usually of animal models. Magnetic Resonance Imaging can partially fill the breach, allowing the portrayal of the macroscopic processes surfacing on in-vivo samples. Different metrics have been defined to measure cortical structure to describe the brain’s morphological changes and infer the associated microstructural events. Metrics such as cortical thickness, surface area, or cortical volume help establish a relation between the measured voxels on a magnetic resonance image and the underlying biological processes. However, the existing methods present limitations or room for improvement. Methods extracting the lines representing the gyral and sulcal morphology tend to over- or underestimate the total length. These lines can provide important information about how sulcal and gyral regions function differently due to their distinctive ontogenesis. Nevertheless, some methods label every small fold on the cortical surface as a sulcal fundus, thus losing the perspective of lines that travel through the deeper zones of a sulcal basin. On the other hand, some methods are too restrictive, labeling sulcal fundi only for a bunch of primary folds. To overcome this issue, we have proposed a Laplacian-collapse-based algorithm that can delineate the lines traversing the top regions of the gyri and the fundi of the sulci avoiding anastomotic sulci. For this, the cortex, represented as a 3D surface, is segmented into gyral and sulcal surfaces attending to the curvature and depth at every point of the mesh. Each resulting surface is spatially filtered, smoothing the boundaries. Then, a Laplacian-collapse-based algorithm is applied to obtain a thinned representation of the morphology of each structure. These thin curves are processed to detect where the extremities or endpoints lie. Finally, sulcal fundi and gyral crown lines are obtained by eroding the surfaces while preserving the structure topology and connectivity between the endpoints. The assessment of the presented algorithm showed that the labeled sulcal lines were close to the proposed ground truth length values while crossing through the deeper (and more curved) regions. The tool also obtained reproducibility scores better or similar to those of previous algorithms. A second limitation of the existing metrics concerns the measurement of sulcal width. This metric, understood as the physical distance between the points on opposite sulcal banks, can come in handy in detecting cortical flattening or complementing the information provided by cortical thickness, gyrification index, or such features. Nevertheless, existing methods only provided averaged measurements for different predefined sulcal regions, greatly restricting the possibilities of sulcal width and ignoring the intra-region variability. Regarding this, we developed a method that estimates the distance from each sulcal point in the cortex to its corresponding opposite, thus providing a per-vertex map of the physical sulcal distances. For this, the cortical surface is sampled at different depth levels, detecting the points where the sulcal banks change. The points corresponding to each sulcal wall are matched with the closest point on a different one. The distance between those points is the sulcal width. The algorithm was validated against a simulated sulcus that resembles a simple fold. Then the tool was used on a real dataset and compared against two widely-used sulcal width estimation methods, averaging the proposed algorithm’s values into the same region definition those reference tools use. The resulting values were similar for the proposed and the reference methods, thus demonstrating the algorithm’s accuracy. Finally, both algorithms were tested on a real aging population dataset to prove the methods’ potential in a use-case scenario. The main idea was to elucidate fine-grained morphological changes in the human cortex with aging by conducting three analyses: a comparison of the age-dependencies of cortical thickness in gyral and sulcal lines, an analysis of how the sulcal and gyral length changes with age, and a vertex-wise study of sulcal width and cortical thickness. These analyses showed a general flattening of the cortex with aging, with interesting findings such as a differential age-dependency of thickness thinning in the sulcal and gyral regions. By demonstrating that our method can detect this difference, our results can pave the way for future in vivo studies focusing on macro- and microscopic changes specific to gyri or sulci. Our method can generate new brain-based biomarkers specific to sulci and gyri, and these can be used on large samples to establish normative models to which patients can be compared. In parallel, the vertex-wise analyses show that sulcal width is very sensitive to changes during aging, independent of cortical thickness. This corroborates the concept of sulcal width as a metric that explains, in the least, the unique variance of morphology not fully captured by existing metrics. Our method allows for sulcal width vertex-wise analyses that were not possible previously, potentially changing our understanding of how changes in sulcal width shape cortical morphology. In conclusion, this thesis presents two new tools, open source and publicly available, for estimating cortical surface-based morphometrics. The methods have been validated and assessed against existing algorithms. They have also been tested on a real dataset, providing new, exciting insights into cortical morphology and showing their potential for defining innovative biomarkers.Programa de Doctorado en Ciencia y TecnologĂ­a BiomĂ©dica por la Universidad Carlos III de MadridPresidente: Juan Domingo Gispert LĂłpez.- Secretario: Norberto Malpica GonzĂĄlez de Vega.- Vocal: Gemma Cristina MontĂ© Rubi

    Constitutions of Value

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    Gathering an interdisciplinary range of cutting-edge scholars, this book addresses legal constitutions of value. Global value production and transnational value practices that rely on exploitation and extraction have left us with toxic commons and a damaged planet. Against this situation, the book examines law’s fundamental role in institutions of value production and valuation. Utilising pathbreaking theoretical approaches, it problematizes mainstream efforts to redeem institutions of value production by recoupling them with progressive values. Aiming beyond radical critique, the book opens up the possibility of imagining and enacting new and different value practices. This wide-ranging and accessible book will appeal to international lawyers, socio-legal scholars, those working at the intersections of law and economy and others, in politics, economics, environmental studies and elsewhere, who are concerned with rethinking our current ideas of what has value, what does not, and whether and how value may be revalued

    Science and Innovations for Food Systems Transformation

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    This Open Access book compiles the findings of the Scientific Group of the United Nations Food Systems Summit 2021 and its research partners. The Scientific Group was an independent group of 28 food systems scientists from all over the world with a mandate from the Deputy Secretary-General of the United Nations. The chapters provide science- and research-based, state-of-the-art, solution-oriented knowledge and evidence to inform the transformation of contemporary food systems in order to achieve more sustainable, equitable and resilient systems

    Exploring new avenues for the meta-analysis method in personality and social psychology research

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    This dissertation addresses theoretical validity and bias in meta-analytic research in personality and social psychology research. The conceptual starting point of the dissertation is research on ego depletion (Baumeister et al., 1998). In this line of research, hundreds of studies documented an experimental effect that probably does not exist, as was later revealed by extensive replication work (Hagger et al., 2010, 2016). This debacle has presumably been caused by dysfunctional structures and procedures in psychological science, such as widespread publication bias (Carter & McCullough, 2014). Unfortunately, these dysfunctionalities were (and in some cases still are) also prevalent in other areas of psychological research beside ego depletion (Ferguson & Brannick, 2012; Open Science Collaboration, 2015). Because extensive replication research is too costly to be repeated for all past work, it has been a contentious question what to do with research data that has been generated during an era of questionable research practices: should this research be abandoned or can some of it be salvaged? In four research papers, this dissertation project attempts to address these questions. In part I of the dissertation project, two papers highlight and analyze challenges when summarizing past research in social psychology and personality research. Paper 1 (Friese et al., 2017) attempted to find summary evidence for the effectiveness of self-control training, a research field related to ego depletion, but came to a sobering conclusion: The summary effect was small, likely inflated by publication bias, and could not be attributed beyond doubt to a theoretical mechanism. Paper 2 (Friese & Frankenbach, 2020) reported on a simulation study that showed how multiple sources of bias (publication bias, p-hacking) can interact with contextual factors and each other to create significant meta-analytic evidence from very small or even zero true effects. Part II of the dissertation project is an attempt to advance social-psychological and personality theory with meta-scientific work despite an unknowable risk of bias in the literature. In part II, two papers (Frankenbach et al., 2020, 2022) make use of one key idea: Re-using existing raw research data to test novel theoretical ideas in secondary (meta-)analyses. Results revealed that this idea helps towards both goals of the dissertation project, that is, advancing theory while reducing risk-of-bias. The general discussion analyses promises and limitations of such secondary data analyses in more detail and attempts to situate the idea more broadly in the psychological research toolkit by contrasting integrative versus innovative research. Further discussion covers how conceptual and technological innovations may facilitate more secondary data analyses in the future, and how such advances may pave the way for a slower, more incremental, but truly valid and cumulative psychological science.Die vorliegende Dissertation behandelt theoretischen ValiditĂ€t und Verzerrung (Bias) von meta-analytischer Forschung in der Persönlichkeits- und Sozialpsychologie. Der konzeptuelle Ausgangspunkt der Dissertation ist die Forschung zu „Ego Depletion“ (Baumeister et al., 1998). In dieser Forschungslinie haben hunderte von Studien einen Effekt belegt, der, wie sich spĂ€ter durch umfangreiche Replikationsarbeiten (Hagger et al., 2010, 2016) herausstellte, vermutlich nicht existiert. Dieses Debakel wurde mutmaßlich mitverursacht durch dysfunktionale Strukturen und Prozesse in der psychologischen Forschung, insbesondere Publikationsbias („publication bias“). UnglĂŒcklicherweise lagen (und liegen) diese DysfunktionalitĂ€ten neben Ego Depletion auch in anderen psychologischen Forschungsbereichen vor (Ferguson & Brannick, 2012; Open Science Collaboration, 2015). Da aus KostengrĂŒnden nicht alle Forschungsarbeiten der Vergangenheit repliziert werden können, ergibt sich eine kritische Frage: Wie soll mit psychologischer Forschung umgegangen werden, die unter mutmaßlich verzerrenden Bedingungen generiert wurde? Sollte diese Forschung ad acta gelegt werden oder können Teile davon weiterverwendet werden? Das vorliegende Dissertationsprojekt versucht im Rahmen von vier ForschungsbeitrĂ€gen sich diesen Fragen anzunĂ€hern. Im ersten Teil der Dissertation beleuchten und analysieren zwei ForschungsbeitrĂ€ge Probleme und Herausforderungen, die sich bei der Zusammenfassung von bestehender Forschung der Sozial- und Persönlichkeitspsychologie ergeben. Der erste Beitrag (Friese et al., 2017) versucht in einer Meta-Analyse Evidenz fĂŒr die Wirksamkeit von Selbstkontrolltrainings zu finden, aber kommt zu einem ernĂŒchternden Ergebnis: Die Gesamteffekte sind klein, mutmaßlich durch Publikationsbias fĂ€lschlich ĂŒberhöht und können ĂŒberdies nicht zweifelsfrei einem theoretischen Kausalmechanismus zugeordnet werden. Der zweite Beitrag (Friese & Frankenbach, 2020) umfasst eine Simulationsstudie, die aufzeigt, wie verschiedene Formen von Bias (Publikationsbias und sog. „p-hacking“) miteinander und mit Kontextfaktoren interagieren können, wodurch signifikante, meta-analytische Effekte aus sehr kleinen wahren Effekten oder sogar Nulleffekten entstehen können. Der zweite Teil der Dissertation versucht, trotz eines unbestimmbaren Bias-Risikos, Fortschritte in der sozial- und persönlichkeitspsychologischen Theorie zu erzielen. Zu diesem Zweck wird in zwei ForschungsbeitrĂ€gen (Frankenbach et al., 2020, 2022) auf eine SchlĂŒssel-Idee zurĂŒckgegriffen: Die Testung von neuen theoretischen Hypothesen unter Wiederverwendung von existierenden Forschungsdaten in SekundĂ€rdatenanalysen. Die Ergebnisse zeigen, dass dieser Ansatz tatsĂ€chlich dazu beitragen kann, theoretische Fortschritte mit vermindertem Verzerrungsrisiko zu machen. Die anschließende, ĂŒbergreifende Diskussion behandelt Möglichkeiten und Limitationen solcher SekundĂ€rdatenanalysen und versucht, den Ansatz in einer GegenĂŒberstellung von integrativer und innovativer Forschung ĂŒbergreifender in die psychologische Forschungsmethodik einzuordnen. Im Weiteren wird diskutiert, wie konzeptuelle und technologische Entwicklungen in der Zukunft SekundĂ€rdatenanalysen erleichtern könnten und wie solche Fortschritte den Weg ebnen könnten fĂŒr eine langsamere, inkrementelle, aber wahrhaft valide und kumulative psychologische Wissenschaft.German Research Foundation (DFG): "Die Rolle mentaler Anstrengung bei Ego Depletion

    Barbarian Europe

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    European culture has been greatly influenced by the Christian Church and Greek and Roman culture. However, the peoples of Europe’s remote past, whom the Greeks, Romans, and their medieval heirs called the «barbarians», also left their mark. Closely examining ancient and medieval narratives and the codifications of laws, this thoughtfully conducted comparative study sheds light on the illiterate societies of the early Germanic and Slavic peoples. The picture that emerges is one of communities built on kinship, neighborly, and tribal relations, where decision making, judgement, and punishment were carried out collectively, and the distinction between the sacred and profane was unknown

    A Corrective Justice Account of Building Authority Liability in Canadian Negligence Law

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    In its decisions in Kamloops v Neilsen and Rothfield v Manolakos, the Supreme Court of Canada adopted a policy-driven justification for imposing liability on building authorities whenever the negligent exercise of their building regulation mandate led to any member of the public suffering any form of foreseeable loss. From its beginnings, this legal doctrine was incoherent and unjustified. It has also become an aberration within Canadian law as, beginning with the decision in Cooper v Hobart, the Supreme Court of Canada resiled from its earlier policy-based approach to imposing liability. What is required is a repudiation of the current legal doctrine, and its replacement by a new understanding of building authority liability. This new understanding is based on corrective justice, at a theoretical level, and a rights-based understanding of negligence law, at the doctrinal level. The current basis of building authority liability, with liability arising from the ability to foresee possible future losses, should be replaced by an inquiry into whether a building authority acted in such a way that it assumed responsibility to a particular person and caused that person to shift their behavior in detrimental reliance on that assumption. This new basis for building authority liability is assisted by the recent development within Canadian law of a rights-based understanding of claims for negligent misrepresentation and negligent performance of a service, an understanding that specifically employs the concept of an assumption of responsibility. Adapting this approach to building authority liability will allow it to be coherent both internally and with the wider field of Canadian negligence law
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