The chapter provides an overview of the field of biosecurity mostly as it developed in the US. It begins by providing essential insights about historical and political developments in the biosecurity arena. It shows that biosecurity has origins as early as World War II, when the fighting parties were developing both biological weapons and countermeasures. Since then and to this day, the biosecurity apparatus has evolved to face various kinds of threats including accidental, intentional and unintentional release of pathogens – each deserving appropriate action. The chapter then directs its attention to the most recent development, namely the risk that well-intended life sciences research might be abused to cause harm – i.e. dual-use research of concern. To illustrate the biosecurity risks of dual-use research, the chapter uses the H5N1 controversy as a case study. Through describing the H5N1 case, the chapter delineates the biosecurity risks it generated and the various ways in which US policy has evolved to address them. It demonstrates that the US government as well as international bodies have been moving away from the notion that scientists should police themselves with regard to dual-use research towards an understanding that specific regulations are needed in order to protect national security and public health.
Struck by the solitary beauty of the nightingale’s song, poets and musicians across the literatures of Renaissance Europe drew on an ancient literary topos to contemplate its meaning. Lamenting a lost love, grieving chicks fallen under the plow, puffing and strutting on the springtime prowl: whatever it was, the little bird became an emblem of the work of poetry itself, transmuting experience into song to be captured and transcribed. Yet a parallel branch of this tradition was attracted to another quality of the nightingale’s song—to its pure vocality, its very senselessness. Rather than hear birdsong as a kind of human speech, this countertradition was prompted instead to hear human speech as a kind of birdsong. From Greek to Latin to Italian to English, the nightingale topos became a coded invitation to translingual wordplay, sonic experimentation, and, at its limits, the dismissal of sense entirely in favor of a poetics of pure sound.
This description sounds distinctly modern; musicologists and theorists of translation have begun only recently to look beyond the sense of language to what has been called “the material presence of its signifiers.” This essay makes a first attempt to show, however, that these acoustic phenomena in verse have been mostly overlooked by criticism precisely because of their diffidence toward the work of making sense. Virtuosic displays of sound over sense were not only audible in poetry before the Romantic period (where much recent commentary on lyric imitation has congregated) but even familiar, as a game played on the borders between speech and song, written lyric and musical setting, and the polyglot lyric cultures of Renaissance Europe.
During meiosis, gene expression is silenced in aberrantly unsynapsed chromatin and in heterogametic sex chromosomes. Initiation of sex chromosome silencing is disrupted in meiocytes with sex chromosome-autosome translocations. To determine whether this is due to aberrant synapsis or loss of continuity of sex chromosomes, we engineered Caenorhabditis elegans nematodes with non-translocated, bisected X chromosomes. In early meiocytes of mutant males and hermaphrodites, X segments are enriched with euchromatin assembly markers and active RNA polymerase II staining, indicating active transcription. Analysis of RNA-seq data showed that genes from the X chromosome are upregulated in gonads of mutant worms. Contrary to previous models, which predicted that any unsynapsed chromatin is silenced during meiosis, our data indicate that unsynapsed X segments are transcribed. Therefore, our results suggest that sex chromosome chromatin has a unique character that facilitates its meiotic expression when its continuity is lost, regardless of whether or not it is synapsed.
Surprisingly, although the Israeli government adopted unregulated, unorganized, inefficient, uncoordinated, and uninformed governance arrangements during the first wave of COVID-19, the public health outcome was successful, a paradox that this theoretically informed article seeks to explain. Drawing on insights from blame avoidance literature, it develops and applies an analytical framework that focuses on how allegations of policy underreaction in times of crisis pose a threat to elected executives’ reputations and how these politicians can derive opportunities for crisis exploitation from governance choices, especially at politically sensitive junctures. Based on a historical-institutional analysis combined with elite interviews, it finds that the implementation of one of the most aggressive policy alternatives on the policy menu at the beginning of the COVID-19 crisis (i.e., a shutdown of society and the economy), and the subsequent consistent adoption of the aforementioned governance arrangements constituted a politically well-calibrated and effective short-term strategy for Prime Minister Netanyahu.
Despite widespread concern over the alleged rise of conspiracy theories, scholars continue to disagree whether it is possible to distinguish specific kinds of conspiracist accounts that can justifiably be denounced as objectionable. In this article, we review scholarship from multiple disciplines to develop a composite definition of “conspiracy theories proper” (CTP) that violate fundamental norms of democratic discourse. Besides referring to grand conspiracies to account for social phenomena, we argue, such conspiracy theories: (a) assume conspirators’ pervasive control over events and information, (b) construct dissent as a Manichean binary, and (c) employ an elusive, dogmatic epistemology. We discuss the operational potential and limitations of our definition using news user talkbacks on the U.S., British and German online editions of Russia Today (RT), a popular platform among proponents of out-of-mainstream political views. Identifying key operational challenges in the classification of natural discourse, we sketch avenues toward a more rigorous study of contentious political talk.
Specialisation and plasticity are important for many forms of collective behaviour, but the interplay between these factors is little understood. In insect societies, workers are often developmentally primed to specialise in different tasks, sometimes with morphological or physiological adaptations, facilitating a division of labour. Workers may also plastically switch between tasks or vary their effort. The degree to which developmentally primed specialisation limits plasticity is not clear and has not been systematically tested in ecologically relevant contexts. We addressed this question in 20 free-foraging bumble bee (Bombus terrestris) colonies by continually manipulating colonies to contain either a typically diverse, or a reduced (“homogeneous”), worker body size distribution while keeping the same mean body size, over two trials. Pooling both trials, diverse colonies produced a larger comb mass, an index of colony performance. The link between body size and task was further corroborated by the finding that foragers were larger than nurses even in homogeneous colonies with a very narrow body size range. However, the overall effect of size diversity stemmed mostly from one trial. In the other trial, homogeneous and diverse colonies showed comparable performance. By comparing behavioural profiles based on several thousand observations of individuals, we found evidence that workers in homogeneous colonies in this trial rescued colony performance by plastically increasing behavioural specialisation and/or individual effort, compared to same-sized individuals in diverse colonies. Our results are consistent with a benefit to colonies of large and small specialists under certain conditions, but also suggest that plasticity or effort can compensate for reduced (size-related) specialisation. Thus, we suggest that an intricate interplay between specialisation and plasticity is functionally adaptive in bumble bee colonies.
This article traces the place of the Book of Esther in George Eliot’s Daniel Deronda, and argues that the biblical work can be seen as Eliot’s primary “map” in her own project of literal and metaphorical remapping. Historical and cultural contexts, as well as close readings of the texts, suggest that the Book of Esther is especially relevant because it engages with the “Jewish Question” and the “Woman Question” in tandem; it offers a terrain for the novel’s ideas on both issues, while precipitating a revised hermeneutic of the biblical text. Remapping the Book of Esther serves Eliot in advocating for a Jewish return and to the Land of Israel and in spurring discourse towards the depolarization of gendered traits, roles, and relations. However, while Eliot answers the Jewish Question with proto-Zionism, she leaves the Woman Question chillingly unanswered — as does the Book of Esther itself.
March 2021: Channah Damatov is a PhD candidate and Kaete Klausner Fellow in the Department of General and Comparative Literature at the Hebrew University of Jerusalem. Her dissertation explores the Book of Esther in Victorian Literature, with a focus on its reception in three novels, Mary Barton by Elizabeth Gaskell, Villette by Charlotte Brontë, and Daniel Deronda by George Eliot. Her wider research interests include the Bible as literature, immigrant literature (especially as regards homeland and exile, displacement, assimilation, and cultural identity), and gender in literature. Channah lives in Giv’at Shmuel, Israel, with her husband, daughter, and two dogs.
Ultraconfined block copolymer films present non-bulk structures that are highly sensitive to film thickness and are strongly influenced by the wetting properties of the substrate. Here we describe the self-assembly of bottlebrush block copolymers with varying side-chain lengths on different types of substrates. Our results show a pronounced influence of the nature of the substrate on the self-assembled morphology and the surface patterns that evolve during solvent-vapor annealing. In particular, we observe by experiments and simulations a transient, substrate-driven morphology of cylinder-like structures obtained in films of doubly symmetric (i.e., backbone and side-chains) bottlebrush block copolymer despite the general tendency of these polymers to form lamellar structures. The insights gained from this study highlight the ability to use the substrate chemistry for inducing the formation of unique morphologies in bottlebrush block copolymer films.
Nicole Mercer Lindsay, Chen, Chong , Gilam, Gadi , Mackey, Sean , ו Scherrer, Grégory . 2021. “Brain Circuits For Pain And Its Treatment”. Sci Transl Med, 13, 619, Pp. eabj7360. doi:10.1126/scitranslmed.abj7360. תקציר
Pain is a multidimensional experience with sensory-discriminative, affective-motivational, and cognitive-evaluative components. Pain aversiveness is one principal cause of suffering for patients with chronic pain, motivating research and drug development efforts to investigate and modulate neural activity in the brain’s circuits encoding pain unpleasantness. Here, we review progress in understanding the organization of emotion, motivation, cognition, and descending modulation circuits for pain perception. We describe the molecularly defined neuron types that collectively shape pain multidimensionality and its aversive quality. We also review how pharmacological, stimulation, neurofeedback, surgical, and cognitive-behavioral interventions alter activity in these circuits to relieve chronic pain.
The understanding that systemic context and tissue crosstalk are essential keys for bridging the gap between in vitro models and in vivo conditions led to a growing effort in the last decade to develop advanced multi-organ-on-a-chip devices. However, many of the proposed devices have failed to implement the means to allow for conditions tailored to each organ individually, a crucial aspect in cell functionality. Here, we present two 3D-print-based fabrication methods for a generic multi-organ-on-a-chip device: One with a PDMS microfluidic core unit and one based on 3D-printed units. The device was designed for culturing different tissues in separate compartments by integrating individual pairs of inlets and outlets, thus enabling tissue-specific perfusion rates that facilitate the generation of individual tissue-adapted perfusion profiles. The device allowed tissue crosstalk using microchannel configuration and permeable membranes used as barriers between individual cell culture compartments. Computational fluid dynamics (CFD) simulation confirmed the capability to generate significant differences in shear stress between the two individual culture compartments, each with a selective shear force. In addition, we provide preliminary findings that indicate the feasibility for biological compatibility for cell culture and long-term incubation in 3D-printed wells. Finally, we offer a cost-effective, accessible protocol enabling the design and fabrication of advanced multi-organ-on-a-chip devices.
The understanding that systemic context and tissue crosstalk are essential keys for bridg-ing the gap between in vitro models and in vivo conditions led to a growing effort in the last decade to develop advanced multi-organ-on-a-chip devices. However, many of the proposed devices have failed to implement the means to allow for conditions tailored to each organ individually, a crucial aspect in cell functionality. Here, we present two 3D-print-based fabrication methods for a generic multi-organ-on-a-chip device: One with a PDMS microfluidic core unit and one based on 3D-printed units. The device was designed for culturing different tissues in separate compartments by integrating individual pairs of inlets and outlets, thus enabling tissue-specific perfusion rates that facilitate the generation of individual tissue-adapted perfusion profiles. The device allowed tissue crosstalk using microchannel configuration and permeable membranes used as barriers between individual cell culture compartments. Computational fluid dynamics (CFD) simulation confirmed the capability to generate significant differences in shear stress between the two individual culture compartments, each with a selective shear force. In addition, we provide preliminary findings that indicate the feasibility for biological compatibility for cell culture and long-term incubation in 3D-printed wells. Finally, we offer a cost-effective, accessible protocol enabling the design and fabrication of advanced multi-organ-on-a-chip devices.
