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Face evaluation: Findings, methods, and challenges
Get PDFComplex evaluative judgments from facial appearance are made efficiently and are consequential. We review some of the most important findings and methods over the last two decades of research on face evaluation. Such evaluative judgments emerge early in development and show a surprising consistency over time and across cultures. Judgments of trustworthiness, in particular, are closely associated with general valence evaluation of faces and are grounded in resemblance to emotional expressions, signaling approach versus avoidance behaviors. Data-driven computational models have been critical for the discovery of the configurations of features, including resemblance to emotional expressions, driving specific judgments. However, almost all models are based on judgments aggregated across individuals, essentially masking idiosyncratic differences in judgments. Yet, recent research shows that most of the meaningful variance of complex judgments such as trustworthiness is idiosyncratic: explained not by stimulus features, but by participants and participants by stimuli interactions. Hence, to understand complex judgments, we need to develop methods for building models of judgments of individual participants. We describe one such method, combining the strengths of well-established methods with recent developments in machine learning
Programming scheduled self-assembly of circadian materials
Get PDFActive biological molecules present a powerful, yet largely untapped, opportunity to impart autonomous regulation of materials. Because these systems can function robustly to regulate when and where chemical reactions occur, they have the ability to bring complex, life-like behavior to synthetic materials. Here, we achieve this design feat by using functionalized circadian clock proteins, KaiB and KaiC, to engineer time-dependent crosslinking of colloids. The resulting material self-assembles with programmable kinetics, producing macroscopic changes in material properties, via molecular assembly of KaiB-KaiC complexes. We show that colloid crosslinking depends strictly on the phosphorylation state of KaiC, with kinetics that are synced with KaiB-KaiC complexing. Our microscopic image analyses and computational models indicate that the stability of colloidal super-structures depends sensitively on the number of Kai complexes per colloid connection. Consistent with our model predictions, a high concentration stabilizes the material against dissolution after a robust self-assembly phase, while a low concentration allows for oscillatory material structure. This work introduces the concept of harnessing biological timers to control synthetic materials; and, more generally, opens the door to using protein-based reaction networks to endow synthetic systems with life-like functional properties
Discourses of Criminality in Early Christianity
Get PDFMy dissertation complicates and opens new avenues of research on early Christian martyrdom by arguing that the concept of the martyr as an innocent figure who does not deserve to die is dependent on the neglected figure of the guilty criminal who does deserve to die. The first part examines the importance of aesthetics in Roman discourses of justice and how Christians reproduced this in their martyr texts. Criminals were compared or equated with allegedly sub-human creatures who were publicly punished or exploited for spectacle, including slaves and animals. Criminalized Christians were painted with the same brush, but when Christians wrote narratives about martyrs, such as the Martyrs of Lyon, they generally worked to separate martyrs, those who do not deserve to die, from associations with criminals, despite Jesus’s and martyrs’ designation of criminal by authorities. Against negative portrayals of condemned criminals, martyrs were asserted to be pure, beautiful despite tortures, hyper-rational, and human in a way criminals lacked. The second part shows that Christians were also invested in distinguishing dead martyrs from the ghosts of criminals. Biothanatoi, ghosts of the violently dead, often executed criminals, were a feared type of ghosts whose body parts were used in magic, magic that often understood them as suitable for enslavement and punishment. Executed martyrs were thought to be examples of these ghosts, a subject worthy of reproach for critics of Christianity and a concerning misunderstanding or misrepresentation for many Christians. Those critical of Christianity, such as Eunapius and the emperor Julian, would rhetorically heighten their criminality, whereas Christian apologists and teachers, such as John Chrysostom and Tertullian, would defend martyrs by emphasizing their innocence and exaggerating the guilt of other executed people
Tracking Multiyear Sea-Ice Variation in the Arctic Ocean Over Decades With Microseism
Get PDFWe construct a linear model of microseism power as a function of sea-ice concentration and ocean-wave activity with a seismic station located on northern Ellesmere Island. The influence of wind-ice-ocean interactions on microseism has been taken into account. We find the increase in microseism power over the last 32 years reflects the long-term loss of sea ice and increasing ocean-wave activity in the Arctic Ocean likely associated with climate change. We further assess model performance to determine a representative region over which sea-ice concentration and ocean-wave activity most directly influence the microseism power. The seismological methods developed here suggest that there is the potential to augment or refine observations of sea-ice conditions obtained from satellites and from in-situ observations. Seismological methods may thus help determine properties such as sea-ice thickness, which are less amenable to conventional observations, under a changing climate, particularly in remote areas like the High Arctic
Vector AutoRegressive Moving Average Models: A Review
Get PDFVector AutoRegressive Moving Average (VARMA) models form a powerful and general model class for analyzing dynamics among multiple time series. While VARMA models encompass the Vector AutoRegressive (VAR) models, their popularity in empirical applications is dominated by the latter. Can this phenomenon be explained fully by the simplicity of VAR models? Perhaps many users of VAR models have not fully appreciated what VARMA models can provide. The goal of this review is to provide a comprehensive resource for researchers and practitioners seeking insights into the advantages and capabilities of VARMA models. We start by reviewing the identification challenges inherent to VARMA models thereby encompassing classical and modern identification schemes and we continue along the same lines regarding estimation, specification, and diagnosis of VARMA models. We then highlight the practical utility of VARMA models in terms of Granger Causality analysis, forecasting and structural analysis as well as recent advances and extensions of VARMA models to further facilitate their adoption in practice. Finally, we discuss some interesting future research directions where VARMA models can fulfill their potentials in applications as compared to their subclass of VAR models
Diagnostic approach to limbal stem cell deficiency
Get PDFLimbal stem cell deficiency (LSCD) is an important cause of visual and ocular morbidity. Effective diagnosis and management require a thoughtful and comprehensive evaluation of the ocular surface. This review describes the pathogenesis, diagnosis, and grading of LSCD, as well as characteristic findings via slit lamp examination, in-vivo confocal microscopy, anterior segment optical coherence tomography (AS-OCT), impression cytology, and OCT angiography
The Dynastic Impulse: Mamluk Husbands, Nomadic Wives, and Family Ambitions in the Early Sultanate
Get PDFThis article is an investigation of the importance of family to the early mamluks. I contend that mamluk desires to connect with their natal families at times countered the mamluk system itself with its creation of bonds between men who were not genetically related to one another. In the present article I begin to address the idea of a “Dynastic Impulse” in the period 648–89/1250–90. By “Dynastic Impulse,” I mean the attempts by the first mamluk rulers and their rivals, especially the initial generation of “Bahris,” to attach themselves to existing dynastic families, to create new families, or to do both, in response to political pressures in the early sultanate
Social Mobility and Political Power: Turkification Processes in the Mamluk Sultanate
Get PDFIn the Mamluk Sultanate there were opportunities for social advancement of individuals who adopted Turkish cultural features. This phenomenon, which may be designated Turkification or Mamlukization, has received little attention in Mamluk studies, even though it played a significant role in social mobility throughout the Sultanate. Turkification in the context of this article applies to the embracing of cultural markers and practices that were common among the ruling elite—the atrāk—and identified with it
GISing Baybars: Unraveling the Odd Location of Maqām Nabī Mūsá
Get PDFMaqām Nabī Mūsá’s contested history, conflicting traditions as to its “true” location, and the role it played in the Israeli-Palestinian conflict all make for a fascinating case in point to explore the ways sacred places are constructed, produced, and perceived by different stakeholders and groups. In this paper, I aim to demystify some of the enigmas regarding this pilgrimage and sacred place, focusing mostly on offering an explanation of its rather humble and seemingly problematic and inaccessible location. To that end, the paper starts with a theoretical analysis regarding the inherently contested nature of sacred places. This is followed with an examination of the site’s location and situation to demonstrate how problematic and intriguing the location chosen for this compound is. Next, I focus on the crucial role of Sultan Baybars and his motivations in constructing the compound. The final part of the paper engages in a Geographic Information System (GIS) inquiry into its location. This, I argue, allows for a better understanding of Baybars’ motivations for locating the disputed tradition of Moses’ burial in an unlikely, mostly unseen, and rather inaccessible location